NFIRS Data Analysis

National Fire Incident
Reporting System
Version 5.0
Fire Data Analysis
Guidelines and Issues
July 2011

National Fire Incident
Reporting System Version 5.0
Fire Data Analysis
Guidelines and Issues
July 2011

U.S. Department of Homeland Security
United States Fire Administration
National Fire Data Center

TABLE OF CONTENTS

INTRODUCTION...................................................................................................................................... 1
NFIRS 5.0 DATA STRUCTURE................................................................................................................ 1
MODULE-BASED SYSTEM....................................................................................................................................................... 1
NFIRS PDR FILES.................................................................................................................................................................... 2
EARLIER VERSION DATA......................................................................................................................................................... 3

DATA MANAGEMENT.............................................................................................................................. 3
SUGGESTED SOFTWARE/DATABASE SYSTEMS.................................................................................................................... 3
CREATING IDENTIFICATION KEYS AND SETTING REFERENTIAL INTEGRITY FOR RELATIONAL DATABASES..................... 3
UNIQUE IDENTIFIERS............................................................................................................................................................. 3
ISSUES.................................................................................................................................................................................... 5

Referential Integrity.................................................................................................................................................................................5
Numeric Data Conversion.......................................................................................................................................................................5

DATA QUALITY........................................................................................................................................ 6
NULL VALUES IN REQUIRED FIELDS..................................................................................................................................... 6
FACTOR FIELDS....................................................................................................................................................................... 6
IDENTIFYING LARGE OUTLIERS............................................................................................................................................. 7

NFIRS 5.0 ANALYSIS CONSTRAINTS AND CONSIDERATIONS............................................................. 7
MUTUAL AID............................................................................................................................................................................ 7
CASUALTY CONSIDERATIONS................................................................................................................................................. 8

Civilian Casualties...................................................................................................................................................................................8
Firefighter Casualties..............................................................................................................................................................................9
EMS Casualties Occurring at Fire Incidents..........................................................................................................................................9

CONFINED FIRES.................................................................................................................................................................. 10
COUNTING FIRES VERSUS COUNTING FIRE-RELATED STATISTICS.................................................................................... 10
TRENDS AND MULTIYEAR ANALYSES.................................................................................................................................. 11
NATIONAL ESTIMATES.......................................................................................................................................................... 11

ANALYSIS OF NFIRS 5.0 DATA............................................................................................................. 11
STATISTICAL CONSIDERATIONS FOR NFIRS DATA............................................................................................................... 12
NULL, BLANK, AND UNKNOWN ENTRIES............................................................................................................................ 12

Evaluating Fields with NULL Values.................................................................................................................................................... 12

FIRE RUNS............................................................................................................................................................................ 12
TOTAL FIRES.......................................................................................................................................................................... 13
TYPES OF FIRES BY INCIDENT TYPE................................................................................................................................... 13
Structure Fires.......................................................................................................................................................................................14
Confined Structure Fires.................................................................................................................................................................14
Nonconfined Structure Fires...........................................................................................................................................................14
Vehicle Fires/Mobile Properties...........................................................................................................................................................15
Outdoor Fires.........................................................................................................................................................................................15
Other Fires.............................................................................................................................................................................................15
Building Fires.........................................................................................................................................................................................16
Confined Building Fires...................................................................................................................................................................17
Nonconfined Building Fires.............................................................................................................................................................17

TYPE OF FIRE BY PROPERTY USE........................................................................................................................................ 18
Property Use Issues.............................................................................................................................................................................. 18
Residential Fires................................................................................................................................................................................... 18
Residential Property Fires.............................................................................................................................................................. 19
Residential Structure Fires............................................................................................................................................................ 19
Residential Building Fires............................................................................................................................................................... 19
Nonresidential Fires............................................................................................................................................................................. 19
Nonresidential Property Fires........................................................................................................................................................ 20
Nonresidential Structure Fires....................................................................................................................................................... 20
Nonresidential Building Fires......................................................................................................................................................... 20
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TABLE OF CONTENTS
OTHER PROPERTY DEFINITIONS......................................................................................................................................... 20
Manufactured Homes.......................................................................................................................................................................... 20
Vacant/Under Construction Buildings, Nonconfined Fires.................................................................................................................21
Occupied Buildings, Nonconfined Fires...............................................................................................................................................21

CASUALTIES........................................................................................................................................................................... 22
Civilian Casualties................................................................................................................................................................................ 22
Civilian Fire Injuries (from Civilian Fire Casualty Module)............................................................................................................ 22
Civilian Fire Deaths......................................................................................................................................................................... 22
Firefighter Casualties........................................................................................................................................................................... 23
Firefighter Injuries........................................................................................................................................................................... 23
Firefighter Deaths........................................................................................................................................................................... 23

DETERMINING CAUSE.......................................................................................................................................................... 23
Structure Fires...................................................................................................................................................................................... 23
Three-Level Structure Fire Cause Hierarchy................................................................................................................................. 25
Mid-Level Structure Fire Cause Hierarchy in Hierarchical Order................................................................................................. 26
Using the NFIRS Cause Categories......................................................................................................................................................27
Vehicle, Outside, and Other Fires........................................................................................................................................................ 28
Cause of Fire Versus Cause of Fire Death/Fire Injury....................................................................................................................... 28
Children Playing.................................................................................................................................................................................... 29
Smoking-Related (Smoking) Versus Smoking Materials................................................................................................................... 29

LOSS MEASURES.................................................................................................................................................................. 29
ANALYSIS OF COMMON DATA ELEMENTS........................................................................................................................... 30
Deaths and Injuries.............................................................................................................................................................................. 30
Civilian............................................................................................................................................................................................. 30
Firefighter........................................................................................................................................................................................ 30
Property and Contents Loss................................................................................................................................................................ 30
Time of Alarm.........................................................................................................................................................................................31
Month and Day......................................................................................................................................................................................31
Time, Month, and Day of Death or Injury.............................................................................................................................................31
Day of Week...........................................................................................................................................................................................31
Elapsed (Response) Time.....................................................................................................................................................................31
Equipment Involved in Ignition............................................................................................................................................................ 32
Fire Spread........................................................................................................................................................................................... 32
Data Elements with Grouped Code Lists............................................................................................................................................ 32
Multiple Entry Data Elements.............................................................................................................................................................. 33
Smoke Alarms....................................................................................................................................................................................... 34
Smoke Alarms in Confined Fires.................................................................................................................................................... 35
Smoke Alarms in Nonconfined Fires............................................................................................................................................. 36
Automatic Extinguishing Systems........................................................................................................................................................37

APPENDIX A: HIERARCHICAL CAUSE MATRIX ................................................................................A-1
APPENDIX B: GENERAL INCIDENT GROUPING BY INCIDENT TYPE AND PROPERTY USE.............B-1
APPENDIX C: NFIRS PDR FILE LAYOUTS...........................................................................................C-1

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NFIRS 5.0 Fire Data Analysis Guidelines and Issues

NFIRS 5.0 DATA STRUCTURE

INTRODUCTION

This document discusses analytic considerations and methods of analyzing fire incident data using the U.S. Fire
Administration’s (USFA’s) National Fire Data Center’s (NFDC’s) National Fire Incident Reporting System (NFIRS),
Version 5.0. The topics include the NFIRS 5.0 data structure, general quality assurance (QA) issues, and definitions and parameters of common fire analyses (e.g., residential structure fires or fires by a specific cause).
The methods, techniques, and considerations discussed are those used by USFA analysts and do not necessarily
reflect methods, techniques, and considerations used by fire data analysts from other agencies and organizations.
NFIRS data partners may (and do) employ their own methods for analyzing the data and may make differing assumptions when encountering data issues.

NFIRS 5.0 DATA STRUCTURE

This section notes some elements of the NFIRS 5.0 data structure that must be understood for general analysis.
The complete structure of NFIRS 5.0 is detailed in the NFIRS Version 5.0 System Documentation. The most recent version
of the system documentation is on the USFA NFIRS website, at http://www.nfirs.fema.gov/documentation/.
NFIRS has undergone several major changes in its 35 years of existence. Originally designed to collect fire incident
data, the current version is an “all incident” reporting system. Fire departments can report on the full range of
their activities, from fire to emergency medical services (EMS) to equipment involved in the response.

Module-Based System

There are currently 11 modules in NFIRS. The Basic Module is the main module, which is completed for every
incident. The other modules are filled out, when appropriate, to provide additional information on an incident.
All 11 modules are listed below:
Module
Basic Module
Fire Module
Structure Fire Module
Civilian Fire Casualty Module
Fire Service Casualty Module
EMS Module
Hazardous Materials Module
Wildland Fire Module
Apparatus/Resources Module
Personnel Module
Arson Module

Description
General information for each incident
Fire incident information
Information on structure fires
Fire-related injuries or deaths to civilians
Injuries or deaths to firefighters
Medical incidents
Hazardous materials incidents
Wildland or vegetation fires
Apparatus-specific information
Personnel associated with apparatus
Intentionally-set fire information

Data from the modules are grouped together each calendar year to create the Public Data Release (PDR) files
which are then released annually. The PDR files consist of a subset of the data fields contained within the NFIRS
national production database. For example, data elements with sensitive or identifying information are removed
as are data elements that are wholly used for maintenance or production purposes. The PDR files’ data structure
has been considerably simplified from the production database for ease of use. The PDR files from 2004 to the
present only include fire and hazmat incidents and their related data tables. Prior to 2004, all incidents were
included in the PDR files.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

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NFIRS 5.0 DATA STRUCTURE
In its basic form, the NFIRS PDR files have a relational data structure where data from each incident module
is represented by a row in a data table. The primary tables (basic incident and incident address) contain most
of the Basic Module data. There is exactly one record in the basic incident table for every incident reported to
NFIRS. All other modules, represented by data tables with similar names (fire incident, civilian casualties, etc.),
have records that are linked to the basic incident table through unique incident identification key fields (e.g.,
STATE, FDID, INC_DATE, INC_NO, and EXP_NO). Some module data are split across several tables (e.g., basic
incident, incident address, and basic aid tables); one table (fire incident) combines data from two modules (i.e.,
Fire Module and Structure Fire Module). Some tables, such as fire incident, will only have one record for each
relevant incident in the basic incident table, while tables such as civilian casualty may have several records
linked to a single incident in the case where multiple injuries and/or deaths occur in the same incident. The
Apparatus/Resources and the Personnel Modules are not available for public release and are not represented in
the PDR files.
The NFIRS PDR files contain the NFIRS 5.0 PDR data table relationship diagram which details the relationships
between the data files.

NFIRS PDR Files

Currently, 19 data tables (files) in .dbf format are included in the NFIRS PDR files. The tables are generally
known by their common name/description. As each table is introduced, the database filename is included in
parentheses. The common names and database table file names are used interchangeably.
The table below should be used as the reference between the common names and the database table file names.
PDR Database File
arson.dbf
arsonagencyreferal.dbf
arsonjuvsub.dbf
basicaid.dbf
basicincident.dbf
civiliancasualty.dbf
codelookup.dbf
ems.dbf
fdheader.dbf
ffcasualty.dbf
ffequipfail.dbf
fireincident.dbf
hazchem.dbf
hazmat.dbf
hazmatequipinvolved.dbf
hazmobprop.dbf
incidentaddress.dbf
legacyfields.dbf
wildlands.dbf

Description

NFIRS Module(s)

Arson incident
Arson agency referral
Arson juvenile subject
Basic incident aid (given/received)
Basic incident (primary data file)
Civilian casualty
Code descriptor lookup
Emergency medical service incident
Fire department information
Firefighter casualty
Firefighter equipment failure
Fire incident
Hazardous material chemical involved
Hazardous material incident
Hazardous material equipment involved
Hazardous material mobile property type
Basic incident address
NFIRS 4.1 legacy field
Wildland fire incident

Arson
Arson
Arson–Juvenile Firesetter
Basic
Basic
Civilian Fire Casualty
Reference
EMS
Reference
Fire Service Casualty
Fire Service Casualty
Fire and Structure
Hazardous Materials
Hazardous Materials
Hazardous Materials
Hazardous Materials
Basic
Reference
Wildland Fire

The dBASE (.dbf file) format is the only format available for the PDR files.
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NFIRS 5.0 Fire Data Analysis Guidelines and Issues

DATA MANAGEMENT

Earlier Version Data

During the transition from the previous version, NFIRS included data collected in the previous format (NFIRS
4.1) and then converted to NFIRS Version 5.0 by the system. For many 4.1 fields and codes, there are oneto-one code conversions that did not change the nature of the original data. However, the analyst should be
aware of data that cannot be converted directly, or where 4.1 data are interpreted rather than directly converted. The 4.1 to 5.0 conversion rules are documented within the National Fire Incident Reporting System Version 5.0 Design
Documentation, (http://www.nfirs.fema.gov/documentation/design/NFIRS_Spec_2009.pdf).
As of January 1, 2009, NFIRS no longer accepts converted 4.1 data.
The USFA has recommended that where a specific research question rests on the correct interpretation of these
specific codes, the analyst should restrict the analysis to NFIRS Version 5.0 data. Incident Type (INC_TYPE)
110, undefined structure fire, is a 4.1 conversion code. Incidents in the NFIRS 5.0 database with a 110 Incident
Type are incidents collected under the NFIRS 4.1 system and are converted to NFIRS 5.0 compatible data. Beginning with the 2002 NFIRS data, USFA staff uses only Version 5.0 in their analyses. Therefore, Incident Type
110 is excluded. These codes are documented in the NFIRS 5.0 Design Document data dictionary section and
designated there as “conversion only” codes.
The original 5.0 and converted 4.1 data could be aggregated with the caveats above and with an understanding
of the code conversions for users interested in broader research inquiries.

DATA MANAGEMENT

This section presents an overview of NFIRS data import issues, use of software/database systems, and ideal
software requirements.

Suggested Software/Database Systems

Database software, system, or statistical software packages for large database manipulation are required to
import and use the NFIRS PDR files since the data files are extremely large and are released in dBASE format
(.dbf). Some candidates for use are MySQL, Microsoft® SQL Server, Statistical Analysis Software (SAS), Statistical Package for the Social Sciences (SPSS), Microsoft® Access, and Oracle.
While current Excel or other spreadsheet programs can be used to open the data files, the use of Excel is not
optimal for manipulating the data.

Creating Identification Keys and Setting Referential Integrity
for Relational Databases

If a relational database is chosen as the preferred system, the user needs to be aware that the PDR files do not
contain a preset identification (ID) key. Relational database systems use ID keys to match records from table
to table. For instance, a basic incident (basicincident.dbf) record may have a related fire incident (fireincident.
dbf) record and multiple civilian (civiliancasualty.dbf) or firefighter casualty (ffcasualty.dbf) records. To match
all of these records together in one query, all of the tables must have ID keys set to link them together.

Unique Identifiers

Records in the PDR files have unique identifiers that follow the pattern in the NFIRS 5.0 PDR Table Relationship Diagram as follows.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

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DATA MANAGEMENT

NFIRS 5.0 PDR Table Relationship Diagram

8/26/2004

FireIncident.dbf
EMS.dbf
Wildlands.dbf
HazMat.dbf

1 to 1
1 to 1
1 to 1
1 to 1

1 to Many

CivilianCasualty.dbf

1 to Many

HazChem.dbf
HazMobProp.dbf
HazMatEquipInvolved.dbf

1 to Many

FDHeader.dbf

Arson.dbf

1 to 1
1 to Many

1 to Many

1 to Many

ArsonJuvSub.dbf
ArsonAgencyReferal.dbf

1 to Many

FFEquipFail.dbf

1 to Many

BasicIncident.dbf
1 to 1
1 to Many

IncidentAddress.dbf
BasicAid.dbf

1 to Many

FFCasualty.dbf

The fire department header table (fdheader.dbf) unique identifier is the combination of the State and fire department ID (STATE, FDID):
Key Field
STATE
FDID

Description
Fire Dept. State
Fire Dept. ID

Data Type
C
X

Length
2
5

Source: Public Data Release Format v1_5.
Note:
C = character; X = mixed character and numeric; N = numeric.

The next level of tables—basic incident (basicincident.dbf), fire incident (fireincident.dbf), emergency medical
services incident (EMS.dbf), wildlands (wildlands.dbf), hazmat (hazmat.dbf), arson (arson.dbf), and incident
address (incidentaddress.dbf)—all share the same unique identifier format. These tables have a one-to-many
relationship with the fdheader table. The unique identifier for these incident-associated records is the combination of the State, fire department ID, incident date, incident number, and exposure number (STATE, FDID,
INC_DATE, INC_NO, and EXP_NO). This combination of fields ensures that every incident has a unique
reference regardless of differences in recordkeeping between fire departments across the country. For example,
the basic aid (basicaid.dbf), hazmat mobile property (hazmobprop.dbf), and hazmat equipment involved
(hazmatequipinvolved.dbf) tables also share this key, but it is not a unique key.
The ID key is used to join different tables in the database together. In some tables, there is a one-to-one match.
In others, there is a one-to-many match. For these tables (one-to-many), there are additional sequence fields
that need to be included as part of the ID key as shown below.
Key Field
STATE
FDID
INC_DATE
INC_NO
EXP_NO

Description
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number

Data Type
C
X
N
X
N

Length
2
5
8 (MMDDYYYY)
7
3

Source: Public Data Release Format v1_5.
Note:
C = character; X = mixed character and numeric; N = numeric.

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NFIRS 5.0 Fire Data Analysis Guidelines and Issues

DATA MANAGEMENT
The following tables require an additional field(s) to create a unique identifier:
Table
civiliancasualty.dbf
hazchem.dbf
ems.dbf
arsonjuvsub.dbf
arsonagencyreferal.dbf
firefightercasualty.dbf
ffequipfail.dbf

Additional Key Field
SEQ_NUMBER
SEQ_NUMBER
PATIENT_NO
SUB_SEQ_NO
AGENCY_NAM
FF_SEQ_NO
CAS_SEQ_NO
EQP_SEQ_NO

Data Type
N
N
N
N
X
N
N
N

Length
3
3
3
3
30
3
3
3

Source: Public Data Release Format v1_5.
Note:
C = character; X = mixed character and numeric; N = numeric.

The key fields are also identified in the NFIRS Public Data Release Format (Version 1.5) that accompanies the
PDR files. This format is also included as Appendix C.

Issues
Referential Integrity
Data cannot be imported directly into an existing NFIRS relational database with established referential integrity because the NFIRS .dbf data tables do not contain ID keys. A relational database with referential integrity
requires that the primary table, basic incident, contain unique ID keys and all records in related tables (e.g.,
fire, casualties) have ID keys that exactly match one record in the basic incident table. USFA does not currently have a QA process to check for inconsistencies in the key fields in the NFIRS basic incident table or in
related tables.1 Therefore, if the data are to be imported into a database, it is suggested to import the data into
a secondary or test database to create and confirm the uniqueness of the keys and resolve any duplicate or mismatched ID keys. A case sensitive collating sequence must be used as upper and lower case letters can appear
in the incident number field. Once the ID keys are established and verified, the tables can then be imported or
copied into the primary database without causing referential integrity errors.
Setting referential integrity is not required to create the database or to do analysis of the NFIRS data. However,
without it, analysts will need to conduct a QA check of the data for mismatched records. Referential integrity is
therefore a useful step in ensuring the quality of the data. Most database systems have tools for setting referential integrity between tables, often using a graphic interface to visually depict the database model.
If other packages (e.g., SAS) are chosen, this step may not be necessary.

Numeric Data Conversion
Data conversion from numeric to date-time data may be necessary for the various date-time data elements. Automatic conversion of numeric data to a text field may convert the data to an integer type, which will truncate
the leading zero and additional data massaging may be necessary.2
1 
2 

Depending on the database system, these records may need to be removed or the entire import process may fail.
For example, an alarm on 01/01/03 at 13:15 (1:15 p.m.) would be formatted as “010120031315” in a text field. Converting this date-time
data to an integer type would truncate the leading zero to produce the number 10,120,031,315.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

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DATA QUALITY
Depending on the database environment, other numeric elements may need to be reviewed for appropriate
data type matches.
Care needs to be taken to ensure the proper importation of fields with null (blank) values. Null values exist in
NFIRS and are not equivalent to zero. Some database products will automatically convert null values to zeros if
care is not taken on the import of data. This will be disastrous for the dollar-loss fields and any other numeric
field where a null value represents “unreported” and a zero means “there were none.”

DATA QUALITY

The USFA does not currently have a QA system in place to check for codes that are not in the current data dictionary. The NFIRS PDR database, as a result, contains invalid codes and may exhibit data inconsistencies that
violate published documentation.
The code lookup table (codelookup.dbf), which is based on the data dictionary (http://www.nfirs.fema.gov/
jsps/nfirsdownload.jsp?url=/documentation/design/NFIRS_Spec_Tables_2009.xls) can be used to validate data
codes. Some codes are added over time, so it is important to use the most recent code lookup table.
Note that hierarchical code placeholders are used for the numeric code values in the data dictionary and in
the code lookup table. These placeholders are not themselves valid codes used for data entry. Instead, they are
used as section titles for code groups and are intended for use in automated pick-lists and database groupings
used by data analysts. They should never be allowed as valid code choices for data entry and should be rejected
as invalid by the NFIRS 5.0 edits. Some examples of code placeholders are “1 Fire” and “10 Fire, other” in the
Incident Type (INC_TYPE) field. These placeholders, however, are not noted in either the data dictionary or
the code lookup table. When in question, refer to the National Fire Incident Reporting System 5.0 Complete Reference Guide
(CRG) (http://www.nfirs.fema.gov/documentation/reference/). If the code in question is not in the CRG, it is
not valid.

Null Values in Required Fields

There remain instances of null values in required fields. As NFIRS 5.0 matures, more and more of these issues
surface and are corrected. Nonetheless, analysts should be aware that null values may occur in required fields
and that a work-around will be necessary. Heat source and structure type are examples where null values have
been an issue. In the case of heat source, null values typically occur in fire incidents where the Fire Module,
that is, detailed fire-related data, is not required (confined fires and outside rubbish fires) and in vegetation,
special outside fires, and crop fires where the Wildland Fire Module can be submitted (and heat source is not
required). In the case of structure type, null values typically occur in fire incidents where the Fire Module is
not required (confined fires).
If null values are found in a required field in the 5.0 data, notify the USFA NFIRS manager of the issue and the specific query or section of a
program that was used to find the error or the specific record (noting the ID key fields) that contains the error.

Factor Fields

Several data items allow multiple entries, such as “factors contributing to ignition” and “human factors contributing to ignition.” In these cases, each entry is distinct. That is, for example, FACT_IGN_1 <> FACT_IGN_2,
where ‘<>’ means not equal. There have been instances when this rule has not been applied correctly or the
edit check to catch the error has not worked properly. Again, if errors are found, notify the USFA NFIRS manager of the
issue and the specific query that was used to find the error or the specific record (noting the ID key fields) that contains the error.
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NFIRS 5.0 Fire Data Analysis Guidelines and Issues

NFIRS 5.0 ANALYSIS CONSTRAINTS AND CONSIDERATIONS
When analyzing the frequency of these factors, the convention established has been to include all factors
mentioned in the data in the frequency distribution. That means the total number of factors (the denominator)
may exceed the number of incidents (or casualties, depending on the factor series under analysis).
The analyst has several choices for techniques:
• Query the data for the distribution of each subfactor variable where the factor is specified. For the example
above, this constraint is where FACT_IGN_X is between 00 and 75 and ensuring no duplicates exist between the factors in an incident. Then, add the results of the queries together. The results from each query
are appended in an Excel spreadsheet, sorted by the FACT_IGN_X column and subtotaled for each factor
value. Because the total number of factors may exceed the number of incidents, the percentage distribution
for the sum of the factors will exceed 100 percent. Percentages can then be derived using the sum of the
first factor as the denominator. (Other methods can be used to achieve the same result.)
• Write code to capture and count each occurrence of the factor code across the variable.
• Manipulate the input data to create a new data table, file, data vector, or other schema that collapses the
multiple fields. Perform the analysis on this user-created schema.
This topic is addressed further in a later section, Analysis of Common Data Elements, that addresses specific data (i.e.,
Multiple Entry Data Elements) elements and how USFA analyzes and interprets the results of the analyses.

Identifying Large Outliers

If the record clearly contains bad data, use a unique value (such as the ID key) to exclude the record from the
query. Before excluding such records, however, it is suggested that a quick search be conducted to see if some
unusual fire did occur. Searching a reputable Internet search engine by the date, State, and the word “fire” will
usually produce a news account if a large fire did, in fact, occur.

NFIRS 5.0 ANALYSIS CONSTRAINTS
AND CONSIDERATIONS

The following sections discuss constraints and issues related to querying and analyzing NFIRS 5.0 data.

Mutual Aid

Some records in NFIRS refer to aid provided to another fire department, either mutual aid given to an outside fire service entity upon request of the outside entity (AID = 3) or automatic aid given through mutual-aid
agreements (AID = 4). To isolate individual fire incidents, only records of the primary fire department are
included. This is achieved by excluding records reflecting aid provided, i.e., excluding records with AID = ‘3’
or ‘4.’ In essence, not excluding aid incidents when analyzing incidents will result in the double counting of those
incidents where both the giving and receiving departments report to NFIRS.
Mutual-aid given incidents (AID = 3 or 4) should always be excluded from all queries with one major
exception: when counting firefighter casualties. Fire departments report only their own firefighter casualties
and not those of a mutual-aid department. Thus, to capture all firefighter injuries, both the incident where the
department received aid and the incident where the department provided aid must be included.
To reiterate, if counting fire service casualties, include aid-given incidents since each fire department (regardless of giving or receiving aid) responding to an incident reports its own firefighter casualties; for everything
else, exclude them.
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NFIRS 5.0 ANALYSIS CONSTRAINTS AND CONSIDERATIONS
Other aid-given (AID = 5) incidents should always be included in all analyses. This code is for incidents
where the aid-giving department is responding to an area that has no fire department of its own (for example,
west Texas). The giving department completes the entire incident report just as if it had occurred in its own
jurisdiction. That incident report is the one and only copy of the incident reported in NFIRS since there is no
aid-receiving department. For that reason, other aid-given (AID = 5) incidents must always be included in
queries. Only mutual aid-given (AID = 3 or 4) incidents must be excluded (again, except when counting firefighter casualties).

Casualty Considerations
Civilian Casualties
Civilian casualties (i.e., injuries and deaths) are tallied in the basic incident table and the details of each casualty are reported in the civilian fire casualty table. To indicate the type and level of the casualty, a 6-level severity
scale (SEV) is used. While civilian injuries have severity values of 1-4, undetermined (U) entries in severity are
also included in the analysis of civilian injuries. Null entries in severity are excluded in analyses of civilian fire
injuries as SEV is a required field. Civilian deaths are noted as SEV = 5. The civilian casualty severity codes are
shown below:
Severity Scale
1
2
3
4
5
U

Definition
Minor
Moderate
Severe
Life Threatening
Death
Undetermined

While the CRG instructs a department completing the Basic Module to include only civilian casualties that are
fire-related, there is a potential issue with counting EMS casualties as civilian fire casualties (see “EMS Casualties Occurring at Fire Incidents”). There are two methods that can be used to derive the number of actual
civilian fire-related casualties:
• Where the incident type is “fire” (i.e., INC_TYPE in the 100 series), the civilian death (OTH_DEATH) and
injury (OTH_INJ) fields from the basic incident table can be summed, or
• The number of civilian fire casualty records for each incident can be totaled from the civilian casualty table.
Each of these methods has drawbacks. The first method is the most straightforward, but there is a chance that
the fire incident may also have nonfire-related EMS casualties which are also included in the total—most likely
a small number, especially since the NFIRS training at the National Fire Academy (NFA) and the National Fire
Information Council (NFIC) reinforces the CRG directions by instructing firefighters and other personnel to
record only civilian fire casualties on the Basic Module Form. To ensure that only fire-related casualties are
included, only fire incidents (i.e., INC_TYPE in the 100 series) are considered.
The second method ensures that only true civilian fire casualties are included in the total but may exclude
some fire casualties because the casualty was reported in the Basic Module but no matching Civilian Fire Casualty Module entry was completed. NFIRS does not require a Civilian Fire Casualty Module to be completed
for each casualty reported on the Basic Module because it may be EMS-related, not fire. Analysts have a choice
between a number that may be slightly high but includes all civilian fire casualties, or a number that may be
low because not all casualties reported on the Basic Module have a matching civilian fire casualty record.
8

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

NFIRS 5.0 ANALYSIS CONSTRAINTS AND CONSIDERATIONS

Firefighter Casualties
As a reminder, unlike civilian casualties and fire counts, mutual aid-given incidents must be included when
using the basic incident table to identify fire service casualties. See the section above on Mutual Aid.
Fire service casualties are tallied in the Basic Module and the details of each casualty are reported in the Fire
Service Casualty Module (regardless of incident type). The SEVERITY field (1-7) is used to indicate the type and
level of the casualty. Fire service deaths in the firefighter casualty file are those with SEVERITY = 7.
NFIRS 5.0 fire service incidents with SEVERITY = 1 are not casualties. This code indicates a report that the
firefighter has been exposed to something that might be harmful to his health at some point in the future
(asbestos, for example). As such, SEVERITY = 1 records are only intended for local fire department documentation of such exposures and are not included as firefighter injuries in data analyses at the national level.
All other SEVERITY entries are considered injuries with the follow exception:
Prior to 2005 NFIRS data, firefighter injuries with null SEVERITY values are included as injuries. Starting
with 2005, firefighter injuries with null severity values are excluded in the injury analyses. SEVERITY became
a required field as of 2005; null values are considered to be invalid entries.
Reported firefighter deaths in NFIRS are fairly rare compared to reported injuries. The valid firefighter casualty
severity codes are shown below:
Severity Scale
1
2
3
4
5
6
7

Definition
Report only, including exposure
First aid only, no lost time
Treated by physician, no lost time
Moderate severity, lost-time injury
Severe, lost-time injury
Life threatening, lost-time injury
Death

EMS Casualties Occurring at Fire Incidents
As NFIRS 5.0 does not have EMS-specific casualty fields on the Basic Module, it is possible that the civilian
casualty counts and fire casualty counts include some EMS casualties, even when the incident type is ‘fire.’ This
is only possible when a fire incident also includes EMS casualties. This is thought to be a rare event.
Since some EMS fatalities may be included in the Basic Module counts in NFIRS 5.0, there may not be one-toone comparisons with the counts in the Basic Module and the number of records in the civilian fire casualty
table or the fire service casualty table. However, there cannot be more injuries or more deaths in the casualty
modules than the counts in the Basic Module.
Therefore, the counts on the Basic Module may be high due to the inclusion of EMS casualties in the casualty
counts and the number of casualty table records (both in the civilian and firefighter casualty tables) may be
less because its completion is no longer enforced.
USFA recommends the use of the basic incident table casualty counts for the following reasons:
1. The NFIRS training classes teach departments only to report fire casualties on the Basic Module, so theoretically, most will be doing it correctly.
NFIRS 5.0 Fire Data Analysis Guidelines and Issues

9

NFIRS 5.0 ANALYSIS CONSTRAINTS AND CONSIDERATIONS
2. The cases where fire and EMS casualties coexist should be fairly rare.
3. It is less likely that the casualty module will be completed and that may represent a substantial undercount.

Confined Fires

Confined fires (Incident Type, INC_TYPE, codes 113–118) do not require a Fire Module and often have no
civilian casualty modules. This results in an increase in the proportion of unknown values when distributing
queries by fire incident or civilian casualty fields (see the later section Null, Blank, and Unknown Entries). There are
two options that could be pursued to ensure that the confined fire null values do not have an undue influence
on the unknown values:
• Limit the analysis to nonconfined fires or to only fires that have a Fire Module (some confined fires do
have fire incident records).
• Separate the analyses into a confined fires version and a nonconfined fires version. The resulting analysis
will be very generic but there are instances where this is reasonable.
USFA generally uses the second option. The exception is when the number of confined fires is very small and
the inclusion or exclusion of them does not significantly change the analysis. In this case, the analysis may or
may not include the confined fires, depending on the judgment of the analyst.
Note that while the NFPA survey includes a category for confined fires, NFPA does not publish estimates of
confined fires. It is unclear what the effect of this has on estimates derived from NFIRS datasets that include
confined fires. An example of one such estimate would be on the number of fires with smoke alarms present,
but not working. The Basic Module gives some information on smoke alarm presence and operation, but not
complete information. The Fire Module gives additional information such as operational status, effectiveness,
power supply, type of alarm, and detector failure reason.

Counting Fires Versus Counting Fire-Related Statistics

When the variable in question is a fire-related variable (i.e., captured under the fire modules—fire, structure
fire, wildland, etc.), fires are counted. When the variable in question is in the casualty modules, casualties are
counted. Even the most seasoned fire data analyst may overlook this distinction from time to time. The proper
phrasing/analysis for casualties counted from fire variables is “fires with casualties/injuries/deaths” or an
equivalent statement.
An example of this is when looking at fatal fires (those fires that result in fatalities) and the fatalities themselves. These two types of analyses are very different. Fatal fires investigate the fire-related variables to analyze
information about the fires that resulted in fatalities. The variables used in the analyses are from the Fire Module. Whereas when analyzing fatalities, the casualties are examined, not the fire. The variables in question are
contained in the casualty modules. As there is a one-to-many relationship between fires and casualties, the
distinction between the analysis of the fire and the analysis of the result of the fire is an important one.
In this vein, analyses such as fires with deaths/injuries, fires causing/resulting in deaths/injuries, and the like
focus on the fire. Analyses such as “fatalities” and “injuries” focus on the casualty.
Fires with loss—property and contents—can also be analyzed separately from fires with no loss reported. Loss
is often difficult to quantify at the incident scene. Often, it may be estimated or not reported at all. As a loss report is not required for all fires, there is some debate whether the appropriate analysis is to treat loss across all
fires, only for those fires where loss is specified, or to derive an average loss and apply it to fires with no loss
reported. The latter analysis assumes that, except in the instances of trash fires that do not burn items of value
10

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA
(including the trash container) and some outdoor vegetation fires, any fire exacts some monetary toll associated with what was lost.
As noted earlier, null values must be carefully imported. As well, analysts need to be aware of their system use
of null values as some systems may produce unusual results when null values are added to numeric values. As
well, there is an issue with the reporting of extremely small losses under the assumption that a value has to be
reported for every fire. In short, dollar-loss analyses must be treated with extreme caution.
For instance, in 2008, a total of 368,232 fires were reported on residential properties. The total loss across these
properties was reported as $4,654,041,727 (property and contents). Not all of the fires reported loss; this loss
was reported from 126,001 of the fires. While the average loss reported across all residential property fires is
$12,639, the average loss for the fires that reported a loss is $36,937—a substantial difference. Loss is considered to be
one of the less reliable data elements in NFIRS, as it is difficult to establish dollar loss without sufficient information or records.

Trends and Multiyear Analyses

It is important to note that NFIRS data may fluctuate from year to year, resulting in variability. It is possible
that any given year may be an anomalous year for a subset of fire data or for the data overall. Statistically rare,
but real-world incidents do occur. Large conflagrations such as the various California wildfires, large petrochemical plant fires such as the 1989 Houston Ship Channel fire, and large multifatality, multiinjury fires such
as the 1980 MGM Grand Hotel fire or the 2003 fire at The Station Nightclub can have one-time effects on fire
analyses for that year.
For these reasons—yearly fluctuation and single-event spikes—it is often preferable to aggregate several years’
data for analyses. USFA uses 3-year averaged data and, where possible, analyzes trends of 5 or more years’ data.
Trends are usually described by the change in the linear best fit. Moving averages are another avenue of trend
analyses available.

National Estimates

National estimates are estimates of the numbers of fire losses (fires, deaths, injuries, dollar loss) associated
with a subset of the fire data. They are not the raw totals from NFIRS. These estimates are based on a method
of apportioning the NFPA estimates for total fires and for vehicle, outside, and other fires. Generally speaking,
national estimates are derived by computing a percentage of fires, deaths, injuries, or dollar loss in a particular NFIRS category and multiplying it by the corresponding total estimate from the NFPA annual survey. This
methodology is the accepted practice of national fire data analysts. The specifics of the methodology are not
discussed here but the methodology may be downloaded from the following NFPA webpage: http://www.
nfpa.org/assets/files/PDF/Research/Nationalestimates.pdf.

ANALYSIS OF NFIRS 5.0 DATA

The following section lists the parameters of common fire analyses. Each type of analysis typically involves
multiple fields and often multiple tables. The values to search for in each field are listed individually, as a
range of inclusive values (e.g., “100–199”), or in some cases a mix of individual values and ranges, separated
by commas (e.g., “100, 140–199,” meaning the individual value 100 and the inclusive range of 140–199). In
some cases, an analysis will look at most of the data in a given field, with the exception of a specific value or
a small range of values. For example, when analyzing nonresidential properties, it is easier to simply exclude
the residential range rather than trying to define everything else. In these examples, the excluded range will
be prefaced with “not” (e.g., “NOT 400–499, exclude NULL”), meaning all values except the inclusive range of
400–499 and nulls. Null values are often treated separately as noted in each section.
NFIRS 5.0 Fire Data Analysis Guidelines and Issues

11

ANALYSIS OF NFIRS 5.0 DATA

Statistical Considerations for NFIRS Data

Any analysis of the NFIRS data should note that NFIRS is neither a random sample nor a census of fire incidents or casualties in the United States. As such, the analyst may not accurately make estimates of total fires,
fire losses, or fire casualties in the United States from NFIRS data alone. Similarly, statistical means (averages) or
standard error measurements taken from NFIRS describe the population of fire incidents related to fire departments that participate in NFIRS, but do not describe the population of fire incidents in the Nation as a whole.
However, the proportion of fire incidents reported to NFIRS is large enough that reasonable inferences can be
made that the proportions of fires in NFIRS are similar to the true national measurements.

Null, Blank, and Unknown Entries

On a fraction of the incident reports or casualty reports sent to NFIRS, the desired information for many data
items either is not reported or is reported as “unknown.” For most coded fields, ‘U,’ ‘UU,’ and ‘UUU’ are
codes available in NFIRS 5.0 to indicate “unknown.” The total number of null, blank, or unknown entries can
be larger than some of the important subcategories. The lack of data masks the true picture of the fire problem.
In some cases, even after the best attempts by fire investigators, the information is truly unknown. In other
cases, the information reported as unknown in the initial NFIRS report is not updated after the fire investigation is completed. When the unknowns are large, the credibility of the data suffers.
In the standard analysis of NFIRS data, the approach taken is to compute two distributions: one that includes all
entries (“raw” distribution) and one that includes only those entries for which data were provided (“known”
distribution). This latter calculation, in effect, distributes the fires for which the data are unknown in the same
proportion as the fires for which the data are known, which may or may not be approximately right.
Null and blank values differ from the variously coded ‘U’ entries in several ways and, depending on the database system used, the accounting of null and blank values may need to be taken into consideration as noted.
It is important to note that null and blank values are considered unreported data and differ in meaning and
substance from “unknown” data. In data elements where information is required, a null or blank value may
invalidate the record.

Evaluating Fields with NULL Values
In the Microsoft® SQL Server environment, a field must have a value to be evaluated in a query expression.
Other platforms may not impose this requirement. This need becomes an issue when the analyst needs to
exclude a range of values from a query. For instance, if one is counting nonresidential incidents and wishes to
exclude the property use range 400–499, then an additional condition needs to be included (when using 2006
to present NFIRS data) to also remove null values.

Fire Runs

The following parameters provide the total number of NFIRS 5.0 fire runs in the database:
Table
Basic Incident
Basic Incident

Field
VERSION
INC_TYPE

Description
Specifies NFIRS version
Type of incident

Value
‘5.0’
100–109, 111–199

Note that mutual-aid incidents are counted as fire runs.

12

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA

Total Fires

Fires are designated by the 100 series Incident Type. Note again that incident type 110 is not a Version 5.0 incident type (INC_TYPE). The following parameters provide the total number of NFIRS 5.0 fires in the database:
Table
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident

Value
‘5.0’
NOT 3–4
100–109, 111–199

Mutual-aid runs are eliminated to avoid double counting of fire incidents.

Types of Fires by Incident Type

The general categories of fire incidents are broadly defined by the type of incident. The table that follows
shows the current designation of general fire incident categories. Parameters specific to each fire incident category (structure, vehicle, outside, and other) are discussed separately in later sections. Fires with undesignated
incident type (INC_TYPE) codes are included in “other” fires.
Note that Incident Type 110 is not included in the following table as it is not a Version 5.0 incident.
Building fires, a subset of structure fires, are discussed in the section Building Fires.
Incident Type
Structure Fires
Confined Fires
Mobile Structure Fires
Mobile Property/Vehicle Fires
Outside Fires
Natural Vegetation Fires
Outside Rubbish Fires
Special Outside Fires
Cultivated Vegetation Fires
Other Fire
Other Fires
Undesignated
Vehicle-Related Fires Where Vehicle Itself Did Not Burn
Outside Gas or Vapor Combustion Explosion
Without Sustained Fire
Undesignated
Undesignated

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Incident Type Code
111–123
113–118
120–123
130–139 (with mobile property
involved (MOB_INVOL) of 1, 3)
140–179 less 163
140–149
150–159
160–169 less 163
170–179
100–109, 130–139 (MOB_INVOL not 1, 3),
163, 180–189, 190–199
100
101–109
130–139 (MOB_INVOL is NULL
or is not 1, 3)
163
180–189
190–199

13

ANALYSIS OF NFIRS 5.0 DATA

Structure Fires
NFIRS 5.0 has an inclusive definition of structure. A structure is a built object and can be a bridge, tower, tunnel, fence, telephone pole, building, or some other built object. Incidents related to structure fires have Incident Types in the range 111–123. The overall structure fires group includes both fixed structures (111–118) and
mobile properties used as fixed structures (120–123).
Note that this category also includes confined fires (INC_TYPE 113–118), which may not always occur in a
structure or building. The following parameters provide the total number of NFIRS 5.0 structure fires:
Table
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident

Value
‘5.0’
NOT 3–4
111–123

When analyzing structure fires, it is necessary to examine what is meant by structure. If the analysis is actually
based on “buildings,” then the structure-type variable needs to be considered in addition to the structure fire
incident types above. The analysis of buildings is discussed in a later section on Building Fires.

Confined Structure Fires3
NFIRS-defined confined structure fires are those fires that did not spread beyond the container of origin (e.g.,
a cooking pan fire that is put out on the stove) and are in the Incident Type (INC_TYPE) range 113–118. Confined fires rarely result in serious injury or large content losses and are expected to have no significant accompanying property losses due to flame damage. NFIRS allows abbreviated reporting for confined structure fires
(as well as some types of confined outdoor fires) and many reporting details of these fires are not required,
nor are they reported (not all fires confined to the object of origin are counted as confined fires). The following parameters provide the number of NFIRS 5.0 confined structure fires:
Table
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident

Value
‘5.0’
NOT 3–4
113–118

NFIRS 5.0 is designed to encourage the reporting of small fires, such as those confined to a stove top or a trash
can. However, it appears that fires with these codes may not be exclusively structure fires nor exclusively confined to object of origin fires. Although they are included in the structure fire range of 111–123, confined fires
may or may not occur in a structure, e.g., confined cooking fires may occur on an outdoor patio.
There are analytic considerations associated with confined fires. These considerations are discussed in the section Building Fires.

Nonconfined Structure Fires
Nonconfined structure fires are those incidents typically associated with larger, more serious fires that progress beyond control and often result in substantial loss and/or casualties. The following parameters provide the
number of NFIRS 5.0 nonconfined structure fires:
3 

14

See also USFA’s report on Confined Structure Fires, February 2006.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA
Table
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident

Value
‘5.0’
NOT 3–4
111, 112, 120–123

Vehicle Fires/Mobile Properties
Vehicle fire incidents (also known as Mobile Property fires) are generally coded with an Incident Type (INC_
TYPE) in the 130 series. Additional criteria must be included to separate those incidents where the vehicle was
involved in ignition, but did not itself burn (MOB_INVOL = 2) as well as those incidents, coded as a vehicular
fire, but do not indicate that mobile property was involved (MOB_INVOL = N). This latter category is unusual
and likely an error. These are fires, but the incident type is most likely miscoded as vehicle fire incidents. The
following parameters provide the total number of NFIRS 5.0 vehicle fires:
Table
Basic Incident
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE
MOB_INVOL

Description
Specifies NFIRS version
Aid provided between departments
Type of incident
Mobile property involved

Value
‘5.0’
NOT 3–4
130–139
1, 3

Outdoor Fires
Outdoor fire incidents are generally coded in the INC_TYPE 140–170 ranges. The exception is INC_TYPE 163,
“outside gas or vapor combustion explosion without sustained fire,” which is considered an “other” fire. The
following parameters provide the total number of outdoor fires in the NFIRS database:
Table
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident

Value
‘5.0’
NOT 3–4
140–179, less 163

For purposes of analysis, Incident Types (INC_TYPE) 154 (dumpster or other outside trash receptacle fire) and
155 (outside stationary compactor or compacted trash fire) are considered as “confined” fires. In addition, Incident Types in the 150 series are not required to complete the Fire Module.

Other Fires
“Other” fire incidents are those miscellaneous fires that do not neatly fit into the major categories. The parameters are detailed in Appendix B, General Incident Grouping by Incident Type and Property Use and the above section, Types
of Fires by Incident Type. The following parameters provide the total number of other fires in the NFIRS database:

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

15

ANALYSIS OF NFIRS 5.0 DATA
Table
Basic Incident
Basic Incident

Field
VERSION
AID

Description
Specifies NFIRS version
Aid provided between departments

Value

Basic Incident

INC_TYPE

Type of incident

Basic Incident
AND
Fire Incident

INC_TYPE

Type of incident

‘5.0’
NOT 3–4
100–109, 163,
180–189, 190–199
130–139

MOB_INVOL

Mobile property involved

NOT 1, 3

Building Fires
By and large, most of the structure fire incidents occur in buildings. Analysis of purely building variables, such
as sprinklers or smoke alarms, however, require that only Structure Types 1 (enclosed building) or 2 (fixed
portable or mobile structure) be considered. This is not only for analytic sense but also to preclude unnecessary null values. That is, only those structure fires that are buildings (Structure Type is a 1 or a 2) are required
to provide data on:
• building status;
• building height;
• main floor size;
• fire origin;
• fire spread;
• presence of detectors (smoke alarms); and
• presence of automatic extinguishing systems.
Analyses on any of these variables that do not restrict the structure type appropriately are not valid. These same
considerations apply to residential and nonresidential buildings below.
The one caveat is that confined structure fire incidents that do not have a structure type specified (STRUC_
TYPE is null) are presumed to occur in buildings. These incidents, however, are not included in the analyses of
the above named variables.
The following parameters provide the total number of NFIRS 5.0 building fires. Note that this category also
includes confined fires (INC_TYPE 113–118), which may not always occur in a building. Also note that different
structure type parameters apply to confined and nonconfined fire incidents:
Table
Basic Incident
Basic Incident
Basic Incident
AND
Fire Incident
Basic Incident
AND
Fire Incident
16

Field
VERSION
AID

Description
Specifies NFIRS version
Aid provided between departments

Value

INC_TYPE

Type of incident (nonconfined fires)

‘5.0’
NOT 3–4
111, 112, 120–123 (pre-2008)
111, 120–123 (from 2008 on)

STRUC_TYPE
INC_TYPE

Type of Structure
Type of incident (confined fires)

1, 2
113–118

STRUC_TYPE

Type of Structure

1, 2, or NULL
NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA
In previous versions of NFIRS, the term “structure” commonly referred to buildings where people live and
work. To coincide with this concept, the definition of a building fire for NFIRS 5.0 has, therefore, changed to
include only those fires where the NFIRS 5.0 Structure Type is 1 or 2 (enclosed building and fixed portable or
mobile structure). Such fires are referred to as “buildings” to distinguish these buildings from other structures
that may include fences, sheds, and other uninhabitable structures. In addition, confined fire incidents that
do not have a structure type specified (STRUC_TYPE is null) are presumed to occur in buildings. Nonconfined fire incidents without a structure type specified are considered to be invalid incidents (structure type is
a required field) and are not included in analyses of building fires. See the next sections on Confined Building Fires
and Nonconfined Building Fires.
Starting with 2008 NFIRS data, the definition of Incident Type 112 was enforced. Early analyses of Incident
Type 112 (fire in structure, other than in a building) indicated that these incidents were often miscoded and
were intended to be building fires. As a result, prior to 2008, Incident Type (INC_TYPE) 112 is included as a
building fire; from 2008 on, it is excluded.

Confined Building Fires
The following parameters provide the number of NFIRS 5.0 confined building fires:
Table
Basic Incident
Basic Incident
Basic Incident
AND
Fire Incident

Field
VERSION
AID
INC_TYPE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident

Value
‘5.0’
NOT 3–4
113–118

STRUC_TYPE

Type of Structure

1, 2, or NULL

Nonconfined Building Fires
The following parameters provide the number of NFIRS 5.0 nonconfined building fires:
Table
Basic Incident
Basic Incident

Field
VERSION
AID

Description
Specifies NFIRS version
Aid provided between departments

Value

Basic Incident
AND
Fire Incident

INC_TYPE

Type of incident

‘5.0’
NOT 3–4
111, 112, 120–123 (pre-2008)
111, 120–123 (from 2008 on)

STRUC_TYPE

Type of Structure

1, 2

Below is an example of a distribution of confined and nonconfined building fires.

Residential Building Smoking-Related Fires by Type of Incident (2006–2008)
Incident Type
Nonconfined fires
Confined fires
Trash or rubbish fire, contained
Cooking fire, confined to container
Commercial compactor fire, confined to rubbish
Total

Percent
94.2
5.8

100.0

5.4
0.2
0.1

Source: NFIRS 5.0.
Note:
It is rare that confined smoking-related fires are associated with cooking and heating. Ninety-three percent of the confined smoking-related fires
are from fires in trash or garbage bins.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

17

ANALYSIS OF NFIRS 5.0 DATA

Type of Fire by Property Use

The general categories of property use are shown in the following table. Residential properties are defined
by including only the 400 series. Nonresidential, or more properly “not residential,” properties are defined
by excluding the 400 series. This exclusion generally means that unknown or blank entries in property use
will automatically be considered nonresidential. Property use is a required field; blank and null values are not
expected (but do occur). Null values in property use receive special treatment as the requirements for certain
types of incidents changed in 2006 and the specifications are discussed in a later section, Nonresidential Fires.
Property Use
Assembly
Eating, drinking places
Educational
Health care, detention, and correction
Residential
1 or 2 family dwelling
Multifamily dwelling
Other residential
Mercantile, business
Industrial, utility, defense, agriculture, mining
Manufacturing, processing
Storage
Detached residential garage
Outside or special property
Property use, other
None
Undetermined

Property Use Code
100 series (if Eating/Drinking separate, less 160 series)
160 series
200 series
300 series
400 series
419
429
400, 439, 449, 459, 460, 462, 464 or 400, 439–499
500 series
600 series
700 series
800 series (if Residential Garage separate, less 881)
881
900 series
000–009
NNN
UUU

Property Use Issues
Prior to January 2006, PROP_USE was not required when AID was 3, 4, or 5. Since then, PROP_USE is required
for AID = 5.4
The mixed use property variable, while available, has not been used by USFA in analyses to date. It is anticipated that analytic issues may be encountered with this data element.

Residential Fires
All incidents that relate to property used for residential purposes will have a property use (PROP_USE) code
in the 400–499 range. The following parameters provide the total number of residential property fires in the
NFIRS database by including the residential property use range:
4 

18

As an aside, for analysts who include the NFIRS 4.1 converted data, the 4.1 conversion to 5.0 may have yielded null or blank values in PROP_
USE when 4.1 was blank or coded as “???”.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA

Residential Property Fires
Table
Basic Incident
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE
PROP_USE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident
Property use

Value
‘5.0’
NOT 3–4
100–109, 111–199
400–499

Residential Structure Fires
The following parameters provide the total number of NFIRS 5.0 residential structure fires in the database by
including the property use range of residential properties:
Table
Basic Incident
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE
PROP_USE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident
Property use

Value
‘5.0’
NOT 3–4
111–123
400–499

Residential Building Fires
The following parameters provide the total number of NFIRS 5.0 residential building fires in the database by
including the property use range of residential properties and enclosed structures:
Table
Basic Incident
Basic Incident

Field
VERSION
AID

Description
Specifies NFIRS version
Aid provided between departments

Value

Basic Incident
AND
Fire Incident
Basic Incident
AND
Fire Incident
Basic Incident

INC_TYPE

Type of incident

‘5.0’
NOT 3–4
111, 112, 120–123 (pre-2008)
111, 120–123 (from 2008 on)

STRUC_TYPE
INC_TYPE

Type of structure (enclosed ….)
Type of incident

1, 2
113–118

STRUC_TYPE
PROP_USE

Type of structure (enclosed ….)
Property use

1, 2, or NULL
400–499

Nonresidential Fires
All incidents that relate to property used for other than residential purposes—‘nonresidential’ properties—are
specified by excluding the residential property use codes (PROP_USE) in the 400 to 499 range. Null values in
property use are included or excluded according to the following rubric:
Prior to 2006, if PROP_USE is NULL and not (400-499), then the incident is “not residential;” from 2006
on, incidents with NULL property use are excluded.
The following parameters provide the total number of nonresidential fires in the NFIRS database by excluding
the property use range of residential properties:

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ANALYSIS OF NFIRS 5.0 DATA

Nonresidential Property Fires
Table
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE

Basic Incident

PROP_USE

Description
Value
Specifies NFIRS version
‘5.0’
Aid provided between departments NOT 3–4
Type of incident
100–109, 111–199
NOT 400–499 or is NULL (pre-2006)
Property use
NOT 400–499 or NOT NULL (from 2006 on)

Nonresidential Structure Fires
The following parameters provide the total number of NFIRS 5.0 nonresidential structure fires in the database
by excluding the property use range of residential properties:
Table
Basic Incident
Basic Incident
Basic Incident

Field
VERSION
AID
INC_TYPE

Basic Incident

PROP_USE

Description
Value
Specifies NFIRS version
‘5.0’
Aid provided between departments NOT 3–4
Type of incident
111–123
NOT 400–499 or is NULL (pre-2006)
Property use
NOT 400–499 or NOT NULL (from 2006 on)

Nonresidential Building Fires
The following parameters provide the total number of NFIRS 5.0 nonresidential building fires in the NFIRS
database by excluding the property use range of residential properties and including only enclosed structures:
Table
Basic Incident
Basic Incident

Field
VERSION
AID

Basic Incident
AND
Fire Incident
Basic Incident
AND
Fire Incident

INC_TYPE

Basic Incident

PROP_USE

Description
Value
Specifies NFIRS version
‘5.0’
Aid provided between departments NOT 3–4
111, 112, 120–123 (pre-2008)
Type of incident
111, 120–123 (from 2008 on)

STRUC_TYPE Type of structure (enclosed ….)
INC_TYPE
Type of incident

1, 2
113–118

STRUC_TYPE Type of structure (enclosed ….)

1, 2, or NULL
NOT 400–499 or is NULL (pre-2006)
NOT 400–499 or NOT NULL (from 2006 on)

Property use

Other Property Definitions
Manufactured Homes
Mobile structures, referred to as Manufactured Homes, are defined as Incident Types between 120 and 123
and property use in the 400 series. This definition may be overly inclusive (see table below) but analyses of
the NFIRS data reveal that many incidents having 120, 122, and 123 Incident Types (INC_TYPE) were coded as
residential properties, implying that the incidents were mobile homes.

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Mobile Structure Incident Type
120
121
122
123

Description
Fire in mobile property used as a fixed structure, other
Fire in mobile home used as fixed residence
Fire in motor home, camper, recreational vehicle
Fire in portable building, fixed location

In NFIRS, manufactured homes are defined as mobile homes used as fixed residences. Manufactured homes are
typically residential trailers, although the distinction between residential trailers and other prefabricated homes
is not as clear as in previous NFIRS versions. In most queries, structures are broadly defined as INC_TYPE
111–123, which include a wide range of buildings and mobile structures, including parked trailers and recreational vehicles. A more strict definition is required to focus on those mobile residential structures that closely
approximate manufactured homes.
Table
Basic Incident
Basic Incident
Basic Incident
Basic Incident
Fire Incident

Field
VERSION
AID
INC_TYPE
PROP_USE
STRUC_TYPE

Description
Specifies NFIRS version
Aid provided between departments
Type of incident
Property use
Type of structure (enclosed only)

Value
‘5.0’
NOT 3–4
120–123
400–499
1, 2

Vacant/Under Construction Buildings, Nonconfined Fires
Vacant/under construction buildings can be involved in any type of nonconfined fire incident and are defined
by the building status field located on the Structure Fire Module. The key criteria are to include STRUC_STAT
= 1 or 4–7, which are vacant or under construction codes. The overall parameters that are used to analyze vacant or under construction properties are below. Residential or nonresidential property use can also be specified (not shown below).
Note that vacant/under construction buildings are analyzed for nonconfined fires only because the building
status is not a required field for confined fires.
Table
Basic Incident
Basic Incident

Field
VERSION
AID

Description
Specifies NFIRS version
Aid provided between departments

Basic Incident

INC_TYPE

Type of incident

Fire Incident
Fire Incident

STRUC_TYPE
STRUC_STAT

Type of structure (enclosed only)
Building status

Value
‘5.0’
NOT 3–4
111, 112, 120–123 (pre-2008)
111, 120–123 (from 2008 on)
1, 2
1 or 4–7

Occupied Buildings, Nonconfined Fires
Building status is also used in analyses of alerting systems (typically smoke alarms) and less often in the analyses of suppression systems (sprinklers). For analyses of alarm effectiveness, one of the key issues is whether the
alarm was effective at alerting the occupants. This analyses is done for occupied buildings only (STRUC_STAT
= 2). Analyses have demonstrated that “not actively occupied housing” (vacant or under construction) typically do not include sufficient data in the smoke alarm variables; by only analyzing occupied buildings—where
alarm systems are designed to alert occupants—undetermined and null entries are reduced. The overall paNFIRS 5.0 Fire Data Analysis Guidelines and Issues

21

ANALYSIS OF NFIRS 5.0 DATA
rameters that are used to analyze nonconfined fires in occupied buildings are below. Residential or nonresidential property use can also be specified (not shown below). However, there are some exceptions to analyzing
smoke alarm data for nonconfined fires in occupied buildings only for certain property types (e.g., multifamily
buildings and university housing). For these residential property types, smoke alarm analyses should include
both occupied and unoccupied buildings because of alarm placement, possible interconnection of alarms in new
construction, stricter building codes, and the proximity or closeness of the dwelling units/living quarters
that may allow occupants to hear an alarm, smell smoke, or see flames coming from a neighboring unit. Even
though a fire may start in an unoccupied unit, it is possible that a fire department will be notified either automatically or by an occupant in a neighboring unit.
Table
Basic Incident
Basic Incident

Field
VERSION
AID

Description
Specifies NFIRS version
Aid provided between departments

Basic Incident

INC_TYPE

Type of incident

Fire Incident
Fire Incident

STRUC_TYPE
STRUC_STAT

Type of structure (enclosed only)
Building status

Value
‘5.0’
NOT 3–4
111, 112, 120–123 (pre-2008)
111, 120–123 (from 2008 on)
1, 2
2

Casualties

When analyzing casualties, the basic incident file or the casualty files can be used. These files, however, produce different results because the tallies in the basic incident file may include EMS casualties that occur at the
incident (see the sections above on Casualty Considerations). In the case of firefighter casualties, the tallies in the
basic incident file also include exposure reports that in themselves are not injuries.

Civilian Casualties
Below are the basic parameters that are used to analyze civilian fire injuries and deaths. It is important to note
that since a large number of civilian injuries and deaths occur in residential structures, specifically buildings,
these incidents are typically analyzed. The parameters for residential buildings (and other groupings) are discussed earlier. These parameters would be included with injury parameters below for analyses of fire casualties
in the various property or incident types.

Civilian Fire Injuries (from Civilian Fire Casualty Module)
The following parameters are used to analyze civilian injuries:
Table
Basic Incident
Basic Incident
Civilian Fire Casualty

Field
VERSION
AID
SEV

Description
Specifies NFIRS version
Aid provided between departments
Severity of incident

Value
‘5.0’
NOT 3–4
NOT 5 or is NOT NULL

Civilian Fire Deaths
The following parameters are used to analyze civilian fire deaths:
Table
Basic Incident
Basic Incident
Civilian Fire Casualty
22

Field
VERSION
AID
SEV

Description
Specifies NFIRS version
Aid provided between departments
Severity of incident

Value
‘5.0’
NOT 3–4
5

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA

Firefighter Casualties
When analyzing casualties, the basic incident file or firefighter casualty file can be used. Both files, however,
produce different results. This is because the basic incident file firefighter casualty fields (i.e., FF_DEATH and
FF_INJ) include a large number of casualties from the EMS casualty file. In order to help eliminate the presence of the EMS casualties, the firefighter casualty file should be used. It is important to note, however, that
some EMS casualties may still be counted as firefighter casualties even in the firefighter casualty file.
EMS casualties are present in the basic incident and firefighter casualty files because some incidents include
both EMS and firefighter casualties. To help avoid having EMS casualty counts included in firefighter casualty
counts, it may be necessary to include in the query: firefighter injuries (FF_INJ) are greater than zero or firefighter deaths (FF_DEATH) are greater than zero. By including this clause, the EMS casualties will be excluded
from firefighter casualties.

Firefighter Injuries
The following parameters are used to analyze firefighter injuries:
Table
Firefighter Casualty

Field
VERSION

Description
Specifies NFIRS version

Firefighter Casualty

SEVERITY

Severity of incident

Basic Incident

FF_INJ

Count of firefighter injuries

Value
‘5.0’
NULL or NOT 1, 7 (pre-2005)
NOT 1, 7 or NOT NULL (from 2005 on)
>0

Firefighter Deaths
The following parameters are used to analyze firefighter deaths:
Table
Firefighter Casualty
Firefighter Casualty
Basic Incident

Field
VERSION
SEVERITY
FF_DEATH

Description
Specifies NFIRS version
Severity of incident
Count of firefighter deaths

Value
‘5.0’
7
>0

Issues involving the firefighter casualty file are discussed in the section Casualty Considerations.

Determining Cause

Since the introduction of NFIRS Version 5.0, the implementation of the cause hierarchy has resulted in a steady
increase in the percentages of unknown fire causes. This increase may be due, in part, to the fact that the
original cause hierarchy (described in Fire in the United States 1995–2004, 14th ed.) does not apply as well to Version 5.0. Causal information now collected as part of NFIRS Version 5.0 was not incorporated in the old hierarchy. As a result, many incidents were assigned to the unknown cause category. As the hierarchy was originally
designed for structures, incidents that did not fit well into the structure fire cause categories (e.g., vehicles and
outside fires) were also assigned to the unknown cause category.

Structure Fires
To capture the wealth of data available in NFIRS 5.0, USFA developed a modified version of the previous cause
hierarchy for structure fires as shown in the Three-Level Structure Fire Cause Hierarchy table that follows. The revised
schema provides three levels of cause descriptions: a set of more detailed causes (priority cause description), a
set of mid-level causes (cause description), and a set of high-level causes (general cause description). The priorNFIRS 5.0 Fire Data Analysis Guidelines and Issues

23

ANALYSIS OF NFIRS 5.0 DATA
ity cause description and the cause description existed previously as part of the original cause hierarchy, but
have been expanded to capture the new 5.0 data.
The causes of fires are often a complex chain of events. To make it easier to grasp the “big picture,” the 16
mid-level categories of fire causes such as heating, cooking, and playing with heat source are used by the USFA
in their reports. The alternative is to present scores of detailed cause categories or scenarios, each of which
would have a relatively small percentage of fires. For example, heating includes subcategories such as misuse of
portable space heaters, wood stove chimney fires, and fires involving gas central heating systems. Experience
has shown that the larger mid-level categories are useful for an initial presentation of the fire problem. A more
detailed analysis can follow.
Fires are assigned to one of the 16 mid-level cause groupings using a hierarchy of definitions, approximately
as shown in the Mid-Level Structure Fire Cause Hierarchy in Hierarchical Order table that follows. A fire is included in the
highest category into which it fits on the list. If it does not fit the top category, then the second one is considered, and if not that one, the third, and so on. Once a match is found, the cause is assigned and no further
checking of subsequent categories is done in the matrix. (See Three-Level Structure Fire Cause Hierarchy table note for
an example.)

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NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA

Three-Level Structure Fire Cause Hierarchy
Code
03
04
05
06
07
08
09
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
36
37
38
39
Note:

Priority Cause
Description
Exposure
Intentional
Children Playing
Natural
Fireworks
Explosives
Smoking
Heating
Cooking
Air Conditioning
Electrical Distribution
Appliances
Special Equipment
Processing Equipment
Torches
Service Equipment
Vehicle, Engine
Heat Source or Product Misuse
Equipment Operation Deficiency
Equipment Failure, Malfunction
Other Unintentional
Unclassified Fuel Powered Equipment
Unclassified Electrical
Malfunction
Matches, Candles
Open Fire
Other Open Flame, Spark
Friction, Hot Material
Ember, Rekindle
Other Hot Object
Exposure 2
Unknown
Other Playing
Trash, Rubbish
Investigation with Arson Module
Unclassified Equipment with Other or
Unknown Fuel Source

Code

Cause Description

Code

12
01
02
11
09
09
03
04
05
07
06
07
10
10
08
10
10
15
14
14
15
10

Exposure
Intentional
Playing with Heat Source
Natural
Other Heat
Other Heat
Smoking
Heating
Cooking
Appliances
Electrical Malfunction
Appliances
Other Equipment
Other Equipment
Open Flame
Other Equipment
Other Equipment
Other Unintentional, Careless
Equipment Misoperation, Failure
Equipment Misoperation, Failure
Other Unintentional, Careless
Other Equipment

06
01
01
02
05
05
05
03
03
03
04
03
03
03
05
03
03
07
03
03
07
03

General Cause
Description
Exposure
Firesetting
Firesetting
Natural
Flame, Heat
Flame, Heat
Flame, Heat
Equipment
Equipment
Equipment
Electrical
Equipment
Equipment
Equipment
Flame, Heat
Equipment
Equipment
Unknown
Equipment
Equipment
Unknown
Equipment

06

Electrical Malfunction

04

Electrical

08
08
09
09
08
09
12
13
02
13
16

Open Flame
Open Flame
Other Heat
Other Heat
Open Flame
Other Heat
Exposure
Unknown
Playing with Heat Source
Unknown
Investigation with Arson Module

05
05
05
05
05
05
06
07
01
07
07

Flame, Heat
Flame, Heat
Flame, Heat
Flame, Heat
Flame, Heat
Flame, Heat
Exposure
Unknown
Firesetting
Unknown
Unknown

13

Unknown

07

Unknown

Fires are assigned to a cause category in the hierarchical order shown. For example, if the fire is judged to be intentionally set and a match was
used to ignite it, it is classified as intentional and not open flame because intentional is higher on the list.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

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ANALYSIS OF NFIRS 5.0 DATA

Mid-Level Structure Fire Cause Hierarchy in Hierarchical Order
Cause Category
Exposure
Intentional
Investigation with
Arson Module

Definition
Caused by heat spreading from another hostile fire
Cause of ignition is intentional or fire is deliberately set
Cause is under investigation and a valid NFIRS Arson Module is present

Includes all fires caused by individuals playing with any materials contained in the categories
below as well as fires where the factors contributing to ignition include playing with heat source;
children playing fires are included in this category
Caused by the sun’s heat, spontaneous ignition, chemicals, lightning, static discharge, high
Natural
winds, storms, high water including floods, earthquakes, volcanic action, and animals
Includes fireworks, explosives, flame/torch used for lighting, heat or spark from friction, molten
Other Heat
material, hot material, heat from hot or smoldering objects
Smoking
Cigarettes, cigars, pipes, and heat from undetermined smoking materials
Includes confined chimney or flue fire, fire confined to fuel burner/ boiler malfunction, central
Heating
heating, fixed and portable local heating units, fireplaces and chimneys, furnaces, boilers,
water heaters as source of heat
Includes confined cooking fires, stoves, ovens, fixed and portable warming units, deep fat fryCooking
ers, open grills as source of heat
Includes televisions, radios, video equipment, phonographs, dryers, washing machines, dishwashers, garbage disposals, vacuum cleaners, hand tools, electric blankets, irons, hairdryers,
Appliances
electric razors, can openers, dehumidifiers, heat pumps, water-cooling devices, air conditioners, freezers and refrigeration equipment as source of heat
Includes electrical distribution, wiring, transformers, meter boxes, power switching gear, outElectrical
lets, cords, plugs, surge protectors, electric fences, lighting fixtures, electrical arcing as source
Malfunction
of heat
Includes special equipment (radar, x-ray, computer, telephone, transmitters, vending machine,
office machine, pumps, printing press, gardening tools, or agricultural equipment), processing
Other Equipment
equipment (furnace, kiln, other industrial machines), service, maintenance equipment (incinerator, elevator), separate motor or generator, vehicle in a structure, unspecified equipment
Open Flame, Spark Includes torches, candles, matches, lighters, open fire, ember, ash, rekindled fire, backfire from
(Heat From)
internal combustion engine as source of heat
Other Unintentional, Includes misuse of material or product, abandoned or discarded materials or products, heat
Careless
source too close to combustibles, other unintentional (mechanical failure/malfunction, backfire)
Equipment MisopIncludes equipment operation deficiency, equipment malfunction
eration, Failure
Unknown
Cause of fire undetermined or not reported
Playing with
Heat Source

26

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA

Using the NFIRS Cause Categories
For USFA’s analytic purposes, all structure fires in NFIRS fall into one of the 16 mid-level cause categories,
denoted by a code:
Cause Code
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16

Cause Description
Intentional
Playing with Heat Source
Smoking
Heating
Cooking
Electrical Malfunction
Appliances
Open Flame
Other Heat
Other Equipment
Natural
Exposure
Unknown
Equipment Misoperation, Failure
Other Unintentional, Careless
Investigation with Arson Module

The cause categories include determinations of intent (intentional, investigation, playing, unintentional), accidental fires (smoking, heating, etc.), natural fires, exposure fires, and malfunction fires. The cause is not
reported by the fire department but is interpreted from a combination of entries in the NFIRS modules. To
maintain the cause hierarchy, there are a series of approximately 35 steps, or queries, which assign the fire
incidents into separate priority “bins” which are aggregated to provide cause totals.
Appendix A, Hierarchical Cause Matrix, contains the current matrix of field values that determine each cause. Each
row in the matrix represents an individual step based on its priority level in the cause hierarchy. Some causes
have multiple steps and the steps may not be contiguous. There are two primary methods for counting incidents by cause:
• Create a reporting script in a database management system (e.g., SAS or Microsoft® Sequel Server), which
is a program that runs a series of queries based on the cause matrix. This maintains a count of each cause
category and produces a report of the final cause totals.
• Create a cause field in the basic incident table or create a separate cause table with ID keys, and then run a
series of queries based on the cause matrix to assign a cause code to each structure fire incident record.
Using either method, the incidents must be removed from consideration once they have been assigned a cause.
One can think of the cause categories as a series of bins in which the incident records are separated. Once a set
of records is assigned to a cause (e.g., smoking), those records are figuratively placed in the smoking bin and
are no longer available to be assigned to any cause further down the hierarchical scale. The result of this hierarchy is that the cause categories are mutually exclusive.
The following graphic is an example of an analysis of how fire data are assigned to the cause categories.
NFIRS 5.0 Fire Data Analysis Guidelines and Issues

27

ANALYSIS OF NFIRS 5.0 DATA

Causes of Fatal Residential Building Fires (2006–2008)
Intentional
2.0
1.1

Playing with Heat Source
Smoking
Heating

3.7
4.0
2.3

Cooking
Electrical Malfunction

1.3
0.7

Causes

Appliances
Open Flame
Other Heat
Other Equipment
Natural
Exposure
Equipment Misoperation, Failure
Other Unintentional, Careless

6.5

6.2
4.8

4.3
1.7
1.0
0.7
0.4
0.8
0.5
3.8
2.2

Investigation with Arson Module

4.8

Unknown
0.0

10.0

5.7

18.9

10.8

10.9

8.4

Percent of Residential
Building Fires with
Cause Determined

7.6

Percent of All Fatal
Residential Building Fires

8.5
8.5

14.9
43.0

10.0
20.0
30.0
40.0
Percent of Fatal Residential Building Fires

50.0

Source: NFIRS 5.0.
Note:
Causes are listed in order of the USFA cause hierarchy for ease of comparison of fire causes across different aspects of the fire
problem. Fires are assigned to one of 16-cause groupings using a hierarchy of definitions, approximately as shown in the chart
above. A fire is included in the highest category into which it fits. If it does not fit the top category, then the second one is considered, and if not that one, the third, and so on. For example, if the fire is judged to be intentionally set and a match was used to
ignite it, it is classified as intentional and not open flame because intentional is higher in the hierarchy.

Vehicle, Outside, and Other Fires
While these new cause categories have usefulness for the other property types—vehicle, outside, and other
fires—there are limitations. USFA plans to investigate and develop specific cause categories for vehicle, outside,
and other fires. Until then, the causes of fires for these property types presented in this edition are based on
the distributions for the cause of ignition (CAUSE_IGN) data element located on the fire incident table. This
data element captures a very broad sense of the cause of the fire.
At this time, there is no specific methodology for determining the cause of nonstructure (i.e., vehicle and outside) fires.

Cause of Fire Versus Cause of Fire Death/Fire Injury
There is a subtle, but important, difference in the phrases “cause of fire,” “cause of a fire that results in deaths/
injuries” (i.e., cause of fatal fires or of fires that result in injuries), and “cause of fire deaths.” The latter phrase
is an incorrect application of the fire cause methodology to the one-to-many relationship of fire to deaths and
injuries.
The first phrase, “cause of fire,” is a straightforward application of the NFIRS cause hierarchy to count the
number (or determine the percent) of fires that fall into a particular category. The second phrase, “cause of
a fire that results in deaths/injuries” is also a straightforward application of the hierarchy to count types of
fires—this time to count only those fires where deaths or injuries result. An analysis of casualty-producing
28

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA
fires is an informative analytic task that is very important to understanding the risks of specific behaviors or
circumstances and to better identify life safety issues.
The phrase, “cause of fire deaths,” is a common but misleading measure. Analysts are too often tempted to just
count deaths and injuries without regard to the initiating circumstance—the fire itself. No casualties, regardless of the number, can occur without the single fire event. While multiple fatality or multiple injury fires are
very important to capture, merely counting the casualties these fires produce, while interesting, is not necessarily the best measure of loss. For instance, consider the following fictitious scenario: 100 arson fires produce
300 deaths. The 300 deaths could be the result of say, 99 fires each with 1 death and 1 fire with 201 deaths or
100 arson fires with 3 deaths each. Regardless, 100 fires resulted in the deaths, and it is the 100 fires that need
to be analyzed. In the former case, the one fire with substantial deaths indicates that an out-of-the ordinary
event occurred and merits serious attention. In the latter case, where there are 100 fires of issue, it indicates a
consistent multiple fatality cause that needs further attention.

Children Playing
The NFIRS 5.0 causes, as defined by USFA, no longer address the specific cause of “children playing.” The USFA
has opted for the overall cause of “playing with fire.” To determine, to the extent possible, if a child playing
with a heat source (such as matches or stove top) caused the fire, the analyst will need to include the human
factors contributing to ignition (eight separate factors) equal to seven (age was a factor) in the query criteria,
factors contributing to ignition and other requirements. In addition, an age range or cutoff for the associated
age variable will need to be included. The details of these criteria are noted in Appendix A, Hierarchical Cause
Matrix where priority cause is 5. It is important to note that the priority causes cannot be taken out of context from the matrix; doing
so will include incidents that would have been included in other priority codes based on earlier steps in the matrix. It is recommended that the
entire cause matrix be implemented.

Smoking-Related (Smoking) Versus Smoking Materials
The term “smoking-related fires” applies to those fires that are caused by cigarettes, cigars, pipes, and heat
from undetermined smoking materials. USFA differentiates between smoking as a cause of fires and fires ignited by smoking materials. Smoking (or smoking-related fires) is considered a behavioral cause. Fires ignited by
smoking materials are considered as a group of fires where smoking materials were the heat source. The two
sets are similar but not identical. A deliberately-set fire with smoking materials as the heat of ignition would
be considered an “intentional” fire; a fire unintentionally set by someone smoking (cigarettes, cigars, or other
smoking materials) would be considered a “smoking-related fire.”
As well, “smoking-related” or “smoking materials” is not synonymous with cigarettes. Cigarettes, however, are
by far the leading smoking material heat source reported to NFIRS under the ‘open flame and smoking materials’ heat source category. In fact, between 2007 and 2009, cigarettes accounted for 84 percent of smoking
material heat sources and rises to 99 percent when undetermined smoking materials are included.
A general discussion of analytic options for the distribution of “undetermined” and “other” codes can be
found in the section, Data Elements with Grouped Code Lists.

Loss Measures

The fire death and injury rates per 1,000 fires and the total dollar loss (property and content loss) per fire are
important metrics. Typically, when comparing these rates, USFA removes the set of incidents under investigation from the parent set, thereby removing the effect of the incidents under investigation from the comparison
group. An example is shown below.
NFIRS 5.0 Fire Data Analysis Guidelines and Issues

29

ANALYSIS OF NFIRS 5.0 DATA

Loss Measures for Attic and Nonattic Residential Building Fires (3-year average, 2006–2008)
Measure
Average Loss:
Fatalities/1,000 fires
Injuries/1,000 fires
Dollar loss/fire

Attic Residential
Building Fires

Nonattic Residential
Building Fires

2.5
11.2
$38,950

5.5
28.6
$15,550

Source: NFIRS 5.0.
Note:
Average loss for fatalities and injuries is computed per 1,000 fires; average dollar loss is computed per fire and is rounded to the nearest $10.

As can be seen, these loss rates are considerably different. Note, however, as NFIRS is not a statistically-selected
random sample, comparative statements should be made with caution.

Analysis of Common Data Elements

NFIRS is not a census of fires and fire losses. The results of data queries only reflect the numbers of fires and
fire losses reported to NFIRS and not for the Nation as a whole. The analyst has two choices when presenting
results: present the results as a percentage (preferred) or as a national estimate. The latter choice has special
challenges and is generally not employed except to quantify the major areas of fire losses.

Deaths and Injuries
Civilian
Totals for civilian deaths or injuries can be derived by summing the values in the respective fields (OTH_
DEATH, OTH_INJ) in the basic incident table. Alternatively, the casualty records can be used to count deaths
and injuries, noting the issues concerning EMS casualties that may be included in the casualty file. For a more
detailed discussion, see the earlier sections, Casualty Considerations and Casualties.

Firefighter
Unlike civilian casualties, totals for firefighter injuries cannot be derived by summing the values of FF_INJ in
the basic incident table as these totals will include hazardous exposures. To derive the number of firefighter
injuries for a given set of fires, the firefighter casualty records must be counted using the severity criteria noted
earlier. Total firefighter deaths can be derived by summing the values of FF_DEATH with all AID codes included. Alternatively, both deaths and injuries can be counted using the severity criteria noted earlier. Nonetheless,
mutual-aid records must be included for complete counts of firefighter injuries or deaths. For a more detailed
discussion, see the earlier sections, Casualty Considerations and Casualties.

Property and Contents Loss
NFIRS 5.0 distinguishes between “content” and “property” loss. Content loss includes loss to the contents of a
structure due to damage by fire, smoke, water, and overhaul. Property loss includes losses to the structure itself
or to the property itself. Both content and property loss can be found in the Basic Module.
Total loss is the sum of the content loss and the property loss. Analysts are cautioned to be careful adding null
values to nonnull values as the results can be unexpected—another reason to investigate how the chosen database or analytic tool handles null values.

30

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA
For confined fires, the expectation is that the fire did not spread beyond the container (or rubbish for Incident
Type 118) and hence, there was no property damage (damage to the structure itself) from the flames. There
could be, however, property damage as a result of smoke, water, and overhaul.

Time of Alarm
For analytic purposes, the time of the fire alarm (ALARM) is used as an approximation for the general time
the fire started. However, in NFIRS, it is the time the fire was reported to the fire department. Analyzing the
time of alarm data is important because it provides information on when certain types of fires are occurring. A
large amount of information can be obtained by looking at the peak hours when specific types of fires occur.

Month and Day
Numeric to date-time conversion may be necessary. Day of year analyses may reveal specific dates that may or
may not be significant, depending on whether large-loss incidents are reflected or not. Certain types of fires
are more common on certain days of the year or in certain months (e.g., the average number of reported residential building fires on Thanksgiving Day is nearly double that of those on all other days). By analyzing daily
or monthly data, trends can be observed. Additional fire information can also be generated for these peak days
or months. This information can provide the analyst with further insight on a specific fire problem.

Time, Month, and Day of Death or Injury
For deaths and injuries, the date-time analyses are based on the INC_DATE information from the casualty files.
For month and day analyses, there may be valid reasons to use the ALARM data (the date-time data for the incident itself) rather than the casualty data. The same issues with the data and conversions noted above apply. Note
that the time of the incident and the time of the casualty (INJ_DT_TIM) will not (or may not) be the same.

Day of Week
To determine the day of week (e.g., Monday), the analyst may need to use a built-in function in the database
system or use an existing function from the analytic tool (e.g., spreadsheet or SAS). The INC_DATE or ALARM
data may need to be converted to the format required by the function chosen. If the incident timing crosses
dates (i.e., straddles midnight), the analyst may need to make appropriate calculations to account for the time
differential.

Elapsed (Response) Time
Typically, this type of analysis is used for “response times” analyses. If no arrival time (ARRIVAL) is included
or if the calculated response time appears to exceed 24 hours, the incident should be excluded. Incidents
classified as automatic or mutual aid (AID = 3 or 4) should also be excluded to avoid double counting of aid
incidents. Elapsed times are generally grouped in 30-second or 1-minute intervals.
Several caveats need to be kept in mind with respect to analyses of response times. First, they are subject to
a variety of measurement errors when units report their arrival on scene prematurely or belatedly. Second,
response times are frequently not comparable across fire-rescue systems because of the differing manners in
which they are calculated. Also, it is difficult, if not impossible, to measure some components of response
time. As well, care should be taken to accurately account for response times when an alarm time (ALARM) is
very close to midnight and the arrival time (ARRIVAL) will necessarily be the next day. As both alarm and arrival time are specified as MMDDYYYYhhmm, the analyst should remember to include the day as well as the
time in calculating response times.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

31

ANALYSIS OF NFIRS 5.0 DATA
Response times are measured from alarm time to arrival on scene, but there is uncertainty in the data. NFIRS
5.0 defines alarm time as “when the alarm was received by the fire department.” This definition is vague and
subjective. Some departments may read this definition to mean when the notification comes into the 9-1-1 communications center (9-1-1 activation) while others may read it as when the notification comes into the station
(dispatch time). Thus, depending on the interpretation by the department, the times reported to NFIRS may or
may not include call processing and dispatch time, which could typically take between 30 and 120 seconds.

Equipment Involved in Ignition
In a small group of incidents, equipment involved in ignition (EQUIP_INV) is coded as “none involved”
(NNN or nnn) but the heat source (HEAT_SOURC) is coded as operating equipment (heat source is 10-13). If
this occurs, these incidents are recoded as “undetermined” (UUU) in analyses of equipment involved.

Fire Spread
By definition, any confined fire (INC_TYPE 113 to 118) is confined to the object of origin. In terms of fire
spread, this is equivalent to FIRE_SPRD = ‘1.’ Some confined fires also have completed Fire Modules and have a
record in the fire incident table (and may, unfortunately, have values other than FIRE_SPRD = ‘1’ in data prior
to 2006). Therefore, when doing analyses on fire spread that include the confined fire incident types, it is important to segregate those confined fires without a record in the fire incident table and count them as having
FIRE_SPRD = ‘1.’ The assumption cannot be made that, since FIRE_SPRD is a required variable, all null values
result from confined fires and are actually “confined to object of origin.” FIRE_SPRD is only required in the Fire
Module when STRUC_TYPE is a “1” or a “2” (enclosed building or fixed portable or mobile structure) and the
Structure Fire Module is called into play. As a result, there will be some “legitimate” null values.
Further, an error was found in the FIRE_SPRD variable for building fires. In the case where the data years
are prior to 2006 and the “Confined to Origin” (CONF_ORIG) checkbox is set to a value of 1 on data entry, a
value of 1 is also to be inserted into the fire spread (FIRE_SPRD) field. Instead, the USFA software mistakenly
inserts a null value into the FIRE_SPRD field rather than a 1. This null value is not critical because the “1”
value still exists in the CONF_ORIG field in the fire incident table. USFA corrected this issue in the 2006 and
subsequent data. For prior years of data, there is a choice of a data correction or a workaround.
Workaround:
1. When doing analyses for fires confined to the object of origin, check for a value of “1” in the CONF_
ORIG field rather than checking for a “1” in the FIRE_SPRD field (in the fire incident table).
Data Correction/Update:
2. Replace the NULL FIRE_SPRD values in the table with “1.” To do so, run a simple script/procedure against
the fire incident table that says (pseudo code follows):
if INC_TYPE between 113 and 118
and STRUC_TYPE = “1” OR “2” OR NULL
and CONF_ORIG = “1”
replace FIRE_SPRD with “1”

Data Elements with Grouped Code Lists

In most of the data elements with long code lists, regardless of the module, the codes are generally organized
into major categories or groups of like items. When analyzing the resulting distributions, the analyst should
consider both the leading category or group and the major individual code. Incident type and property use
(discussed earlier) are also examples of these types of variables.
32

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA
Primary data elements which follow this general pattern are
INC_TYPE
PROP_USE
AREA_ORIG
HEAT_SOURC
FIRST_IGN
TYPE_MAT
EQUIP_INV

Field

Description
Incident Type
Property Use
Area of Fire Origin
Heat Source
Item First Ignited
Type of Material Ignited
Equipment Involved in Ignition

Basic Incident
Basic Incident
Fire Incident
Fire Incident
Fire Incident
Fire Incident
Fire Incident

Table

Unknown, blank, and null entries are generally considered unknown and are distributed across the other valid
entries (i.e., removed from the analysis) for some of these fields. Treatment of null values in property use is
discussed in the section Nonresidential Fires.
In the very few instances where the major category includes an intermediate “other” code that crosses group
boundaries, analysts may elect to distribute the “other” category across the group of codes. This specifically
applies to heat source (HEAT_SOURC) 60, “heat from other open flame or smoking materials, other.” USFA,
however, does not follow this option for heat source 60 as USFA notes that the “other” category is for items
not already specified in the code group. It is not an “unknown.” As such, no distributing is warranted.5

Multiple Entry Data Elements
Multiple entry data elements require the analyst to combine the distributions from each of the elements into
one overall distribution. Unknown, null, and blank values are not considered and the analysis is performed
“only where a factor was specified or indicated.” The denominator for the distribution is the number of incidents with at least one factor specified. As a result, the total percent distribution can (and usually does) total to
greater than 100 percent.
The same factor value cannot be entered into more than one of the factor elements for an incident. The analyst, however, is well-served to check to ensure this and remove any duplicate values. Succeeding factors can
only be entered if the preceding factor exists and is not N (no factor involved). Again, the analyst should confirm this. See the earlier section on Factor Fields for a more detailed discussion.
Primary data elements which follow this general pattern are
Data Element
FACT_IGN_1 to FACT_IGN_2
HUM_FAC_1 to HUM_FAC_8
FACT_INJ1 to FACT_INJ3
HUM_FACT1 to HUM_FACT8
SUP_FAC_1 to SUP_FAC_3

Description
Factors Contributing to Ignition
Human Factors Contributing to Ignition
Factors Contributing to Injury
Human Factors Contributing to Injury
Fire Suppression Factors

Table
Fire Incident
Fire Incident
Civilian Fire Casualty
Civilian Fire Casualty
Fire Incident

5  USFA

has analyzed heat source code 60 data for 2003, 2006, and 2008 using a stratified random sample of residential structure fires where the
remarks field was completed for those incidents and where the heat source code was 60. The remarks were reviewed and then the heat source
value was recoded to the appropriate value based on the information provided in the remarks field. The results for each year showed that the
majority of the heat source 60 incidents should have been coded as kitchen/cooking fires (heat source 12) or chimney, flue fires (heat source
81 or 43). Very few of the sampled incidents were recoded as cigarettes, candles, or other heat source 60 decade codes. These results showed
that the heat source 60 code should not be distributed as an unknown among the remaining heat source 60 decade codes. USFA and others
strongly agree that the heat source 60 code should not be treated as an unknown and, therefore, should not be distributed over the heat source
61–69 categories.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

33

ANALYSIS OF NFIRS 5.0 DATA
If the factor data element also has grouped code lists, the analyst, as above, should consider both the leading
group and the major individual code. Examples of both analyses are shown below.

Factors Contributing to Ignition for Fatal Residential Building Fires by Major Category
(Where Factor Contributing Specified, 2006–2008)
Factor Contributing to Ignition Category
Misuse of material or product
Electrical failure, malfunction
Other factors contributing to ignition
Operational deficiency
Mechanical failure, malfunction
Fire spread or control
Design, manufacture, installation deficiency
Natural condition

Percent of Fatal Residential Fires
(Unknowns Apportioned)
59.3
15.1
13.2
12.0
4.8
2.7
1.4
1.1

Source: NFIRS 5.0.
Notes: 1) Includes only incidents where factors that contributed to the ignition of the fire were specified.

2) Multiple factors contributing to fire ignition may be noted for each incident; total will exceed 100 percent.

Leading Factors Contributing to Ignition for Nonconfined Residential Building Smoking-Related Fires
(Where Factor Contributing Specified, 2006–2008)
Factor Contributing to Ignition
Abandoned or discarded materials or products
Unspecified misuse of material or product
Heat source too close to combustibles

Percent of Nonconfined Residential Smoking-Related
Fires Where Contributing Factor Specified
66.8
15.2
10.9

Source: NFIRS 5.0.
Notes: 1) Includes only incidents where factors that contributed to the ignition of the fire were specified.

2) Multiple factors contributing to fire ignition may be noted for each incident.

Smoke Alarms
In general, USFA presentation of the smoke alarm data in NFIRS requires a relatively straightforward approach
by separating the available data into smoke alarm data for confined fires and for nonconfined fires. Smoke
alarm data are collected at the fire incident level (not the casualty level). As such, USFA’s analysis of smoke
alarm data is not directly transferable to numbers (or percentages) of deaths and injuries.
Smoke alarm data are collected via seven data elements, one in the basic incident table and six in the fire incident table. The detector alerted occupants (DET_ALERT) field, from the basic incident table, is required for
confined structure fires (but not for nonconfined structure fires). The six other variables are required for nonconfined building fires (those structure fires with STRUC_TYPE = 1, 2) and optional for confined fires (and
not generally reported). The smoke alarm data elements are listed in the following table:

34

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA
Table
Basic Incident
Fire Incident
Fire Incident
Fire Incident
Fire Incident
Fire Incident
Fire Incident

Field
DET_ALERT
DETECTOR
DET_TYPE
DET_POWER
DET_OPERAT
DET_EFFECT
DET_FAIL

Description
Detector Alerted Occupants
Detector Presence
Detector Type
Detector Power
Detector Operation
Detector Effectiveness
Detector Failure Reason

USFA has since abandoned its earlier smoke alarm analysis methodology. Detailed analyses of the data revealed
inconsistencies in interpreting the relationships between the several data elements. These inconsistencies resulted in an overly complex analytic framework that relied on inferred relationships between the smoke alarm
variables. Currently, USFA has opted to present the undistributed data for presence, operation, and effectiveness. Other smoke alarm variables are not analyzed at this time.
USFA analyzes the general presence of smoke alarms for all buildings. For confined fires, the variable DET_
ALERT is used. As confined fires are only required to provide the basic incident data, the analyst does not have
the information to determine the occupancy status. For nonconfined fires, the variable DETECTOR is used.
Because the effectiveness of smoke alarms (i.e., if the occupant heard and responded to the alarm) can only be
measured if occupants are present, detailed analyses on the combination of presence, operation, and effectiveness of smoke alarms are generally undertaken for nonconfined fires in occupied buildings only. There are
exceptions to this general rule, such as in analyses of buildings with multiple occupancies where some occupancies may be in use and others may be vacant, e.g., multifamily buildings.
Note: USFA does not distribute unknowns in its presentation of smoke alarm data.

Smoke Alarms in Confined Fires
The detector alerted occupants (DET_ALERT) data from the basic incident table are only used in the analysis
of smoke alarms in confined structure fires and are used to determine solely whether the alarm alerted the occupant. USFA presents smoke alarm data for confined structure fires that are defined as building fires.
Note: Structure type (STRUC_TYPE), the data element that is used to determine whether a structure is a building, is not required for confined fires. As such, confined fires with no structure type reported are assumed to
be building fires.
Note: If the occupant was not alerted by a smoke alarm, the analyst will not know whether the lack of notification was because:
• no alarm was in the vicinity;
• the alarm did not operate (for whatever reason, including fire too small);
• the smoke alarm was present and operated but the occupant was already aware of the fire; or
• no occupants were present at the time of the fire.
A typical analysis (with data source attribution and analysis notes) is shown in the following table.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

35

ANALYSIS OF NFIRS 5.0 DATA

NFIRS Smoke Alarm Data for Confined Multifamily Residential Building Fires (2005–2007)
Smoke Alarm Effectiveness
Smoke alarm alerted occupants
Smoke alarm did not alert occupants
Unknown
Total Incidents

Count
61,555
19,620
50,656
131,831

Percent
46.7
14.9
38.4
100.0

Source: NFIRS 5.0.
Notes: The data presented in this table are raw data counts from the NFIRS data set. They do not represent national estimates of smoke alarms in confined multifamily residential building fires. They are presented for informational purposes.

Smoke Alarms in Nonconfined Fires
For nonconfined fires, the data elements detector presence (DETECTOR), detector operation (DET_OPERAT), and
detector effectiveness (DET_EFFECT) from the fire incident table are combined to present the full range of smoke
alarm performance and effectiveness in alerting occupants. As these data elements are only required for building
fires and other enclosed structures (logically, where one would expect smoke alarms to be located), only smoke
alarm presence, operation, and effectiveness in building fires are presented. Typically, the presence of smoke
alarms is presented as a stand-alone distribution then combined with the other two variables to present the full
range of smoke alarm performance and effectiveness in nonconfined fires. Examples are shown below.

Presence of Smoke Alarms in Fatal Residential Building Fires (2006–2008)
Presence of Smoke Alarms
Present
None present
Undetermined
Null/Blank

Percent
37.7
22.5
39.7
<0.1

Source: NFIRS 5.0.
Note:
Total may not add to 100 percent due to rounding.

NFIRS Smoke Alarm Data for Fatal Residential Building Fires in Occupied Housing (NFIRS, 2006–2008)
Presence of
Smoke Alarms

Smoke Alarm Operational Status

Smoke Alarm Effectiveness

Fire too small to activate smoke alarm

Present

Smoke alarm operated

Smoke alarm failed to operate
Undetermined
None present
Undetermined
Total Incidents

Smoke alarm alerted occupants,
occupants responded
Smoke alarm alerted occupants,
occupants failed to respond
No occupants
Smoke alarm failed to alert occupants
Undetermined

Count Percent
9

0.3

209

6.5

83

2.6

1
28
147
266
474
706
1,272
3,195

0.0
0.9
4.6
8.3
14.8
22.1
39.8
100.0

Source: NFIRS 5.0.
Notes: The data presented in this table are raw data counts from the NFIRS data set. They do not represent national estimates of smoke alarms in fatal
residential building fires in occupied housing. They are presented for informational purposes. Total will not add to 100 percent due to rounding.

36

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

ANALYSIS OF NFIRS 5.0 DATA

Automatic Extinguishing Systems
Like smoke alarm data, Automatic Extinguishing Systems (AES) data are collected by multiple data elements.
The data elements are shown in the table below:
Table
Fire Incident
Fire Incident
Fire Incident
Fire Incident
Fire Incident

Field
AES_PRES
AES_TYPE
AES_OPER
NO_SPR_OP
AES_FAIL

Description
AES Presence
AES Type
AES Operation
Number of Sprinklers Operating
AES Failure Reason

As noted above, many fires in NFIRS 5.0 are confined fires without matching fire incident records. While
smoke alarms have a data element in the Basic Module that captures some additional alarm data, AES/Sprinkler
data are entirely captured in the fire incident table. To remove the bias that can be introduced by the lack of
data from confined fires (INC_TYPE between 113 to 118), only nonconfined fires are included in analyses, that
is, confined fires have been removed from the query.
At this time, USFA analyzes only the presence of AES.
Note: USFA does not distribute unknowns in its analyses of AES data.
Additional research is necessary on the AES data to further develop appropriate methodologies, as is the ongoing case with the smoke alarm data. The following table shows an example of an analysis of AES data.

NFIRS Automatic Extinguishing System (AES) Data for Vacant Residential Building Fires (2006–2008)
Presence of Automatic
Extinguishing Systems
AES present
Partial system present
AES not present
Unknown
Total Incidents

Count

Percent

474
32
42,600
4,120
47,226

1.0
0.1
90.2
8.7
100.0

Source: NFIRS 5.0.
Notes: The data presented in this table are raw data counts from the NFIRS data set. They do not represent national estimates of AESs in vacant residential building fires. They are presented for informational purposes.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

37

APPENDIX A: HIERARCHICAL CAUSE MATRIX

APPENDIX A: HIERARCHICAL CAUSE MATRIX (REVISED – SEPTEMBER 2015)
Order
Cause Description
#
1
Exposure
2
3
4

Cause
Priority Cause Description
Code
12
Exposure

Intentional

01

Cause Under Investigation

16

Priority
Cause Code
03

Intentional

04

Intentional Wildland

04

Cause Under Investigation

38

5
6

7

Playing with Heat Source

02

Children Playing

05

Playing with Heat Source

02

Other Playing

36

8

Natural

11

Natural

06

Fireworks

07

9
10

11

Other heat

09

Smoking

03

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Explosives

08

Smoking

09

Matrix Code Category Logic
aid NOT BETWEEN ‘3’ AND ‘4’ AND exp_no != 0
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0 AND cause_ign = ‘1’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0 AND fire_cause = ‘7’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0 AND cause_ign = ‘5’
AND case_stat BETWEEN ‘1’ AND ‘5’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND( (fact_ign_1 = ‘19’ OR fact_ign_2 = ‘19’) OR cause_ign = ‘2’ )
AND age_a BETWEEN 1 AND 9
AND (hum_fac_1 = ‘7’ OR
hum_fac_2 = ‘7’ OR
hum_fac_3 = ‘7’ OR
hum_fac_4 = ‘7’ OR
hum_fac_5 = ‘7’ OR
hum_fac_6 = ‘7’ OR
hum_fac_7 = ‘7’ OR
hum_fac_8 = ‘7’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0 AND fire_cause = ‘8’
AND age_b BETWEEN 1 AND 9
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (fact_ign_1 = ‘19’ OR fact_ign_2 = ‘19’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc BETWEEN ‘70’ AND ‘74’
OR cause_ign = ‘4’
OR fact_ign_1 = ‘65’ OR fact_ign_2 = ‘65’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0 AND heat_sourc = ‘54’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc BETWEEN ‘50’ AND ‘53’
OR heat_sourc BETWEEN ‘55’ AND ‘59’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND heat_sourc BETWEEN ‘61’ AND ‘63’

Comments

Former Incendiary/Suspicious category now split into two categories:
Intentional and Cause Under Investigation (formerly called Investigation with Arson Module). Arson Module criteria for selection is Case
Status between 1 and 5.

Children Playing now combined with new ‘other playing’ category.
Can still get ‘children playing’ from Priority Cause Code (PCC) code.
Removed allowance of any age in first checked category.

Check for children involved in setting wildland fire.
Other playing added as new PCC category. Included in cause 02.

Combined with the new ‘natural’ matrix check below.

A-1

APPENDIX A: HIERARCHICAL CAUSE MATRIX
Order
#

Cause Description

Cause
Code

Priority Cause Description

Priority
Cause Code

12
Heating

04

Heating

11

13

Cooking

05

Cooking

12

14

Appliances

07

Air Conditioning

13

15

Electrical Malfunction

06

Electrical Distribution

14

16

Appliances

07

Appliances

15

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Matrix Code Category Logic
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND inc_type != ‘113’ AND first_ign != ‘76’ AND equip_inv BETWEEN ‘123’ AND ‘124’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0 AND (inc_type = ‘114’ OR inc_type = ‘116’)
OR ((equip_inv = ‘100’ OR equip_inv BETWEEN ‘120’ AND ‘122’ OR equip_inv BETWEEN
‘125’ AND ‘152’)
AND inc_type != ‘113’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (inc_type = ‘113’
OR equip_inv = ‘654’
OR equip_inv BETWEEN ‘630’ AND ‘649’
OR (first_ign = ‘76’ AND equip_inv BETWEEN ‘123’ AND ‘124’))
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (equip_inv = ‘445’
OR equip_inv = ‘652’ OR equip_inv = ‘655’
OR equip_inv = ‘656’
OR equip_inv BETWEEN ‘111’ AND ‘117’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (fact_ign_1 = ‘37’ OR fact_ign_2 = ‘37’
OR equip_inv BETWEEN ‘200’ AND ‘223’
OR equip_inv BETWEEN ‘226’ AND ‘227’
OR equip_inv BETWEEN ‘230’ AND ‘299’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (equip_inv BETWEEN ‘310’ AND ‘316’
OR equip_inv BETWEEN ‘318’ AND ‘319’
OR equip_inv = ‘345’
OR equip_inv = ‘600’
OR equip_inv BETWEEN ‘611’ AND ‘612’
OR equip_inv BETWEEN ‘621’ AND ‘623’
OR equip_inv = ‘651’
OR equip_inv = ‘653’
OR equip_inv BETWEEN ‘730’ AND ‘759’
OR equip_inv = ‘800’
OR equip_inv BETWEEN ‘810’ AND ‘869’
OR equip_inv = ‘871’
OR (equip_inv = ‘872’
AND NOT eq_power BETWEEN ‘20’ AND ‘39’)
OR equip_inv BETWEEN ‘874’ AND ‘876’
OR equip_inv BETWEEN ‘881’ AND ‘883’
OR equip_inv BETWEEN ‘891’ AND ‘897’)

Comments
Exclude confined cooking fires. Exclude stove/insert fires where item
first ignited is food.

Include stoves, inserts where item first ignited is food. Also includes
confined food on stove fires.

Category now combined with Unclassified Electrical Malfunction.

A-2

APPENDIX A: HIERARCHICAL CAUSE MATRIX
Order
#

Cause Description

Cause
Code

Priority Cause Description

Priority
Cause Code

17

Special Equipment

16

18

Special Equipment

16

Processing Equipment

17

Other Equipment

19

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

10

Matrix Code Category Logic
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0 AND (inc_type = ‘115’ OR inc_type = ‘117’)
AND ((fact_ign_1 IS NULL AND fact_ign_2 IS NULL)
OR (LEFT(fact_ign_1,1) != ‘1’
AND LEFT(fact_ign_2,1) != ‘1’
AND LEFT(fact_ign_1,1) != ‘2’
AND LEFT(fact_ign_2,1) != ‘2’
AND LEFT(fact_ign_1,1) != ‘5’
AND LEFT(fact_ign_2,1) != ‘5’))
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (equip_inv = ‘224’
OR equip_inv BETWEEN ‘340’ AND ‘344’
OR equip_inv BETWEEN ‘346’ AND ‘349’
OR equip_inv = ‘361’
OR equip_inv BETWEEN ‘372’ AND ‘374’
OR equip_inv BETWEEN ‘376’ AND ‘377’
OR equip_inv = ‘400’
OR equip_inv BETWEEN ‘410’ AND ‘429’
OR equip_inv BETWEEN ‘431’ AND ‘432’
OR equip_inv BETWEEN ‘440’ AND ‘444’
OR equip_inv BETWEEN ‘446’ AND ‘451’
OR equip_inv BETWEEN ‘500’ AND ‘599’
OR equip_inv BETWEEN ‘700’ AND ‘729’)
AND LEFT(fact_ign_1,1) != ‘1’
AND LEFT(fact_ign_2,1) != ‘1’
AND LEFT(fact_ign_1,1) != ‘2’
AND LEFT(fact_ign_2,1) != ‘2’
AND LEFT(fact_ign_1,1) != ‘5’
AND LEFT(fact_ign_2,1) != ‘5’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (equip_inv = ‘300’
OR equip_inv = ‘317’
OR equip_inv BETWEEN ‘320’ AND ‘329’
OR equip_inv = ‘351’
OR equip_inv = ‘353’
OR equip_inv BETWEEN ‘355’ AND ‘358’
OR equip_inv = ‘371’)
AND LEFT(fact_ign_1,1) != ‘1’
AND LEFT(fact_ign_2,1) != ‘1’
AND LEFT(fact_ign_1,1) != ‘2’
AND LEFT(fact_ign_2,1) != ‘2’
AND LEFT(fact_ign_1,1) != ‘5’
AND LEFT(fact_ign_2,1) != ‘5’;

Comments

Category now includes PCC 25 (Unclassified Fuel Powered Equipment). Includes priority check for following ‘factors contributing’
causes.

A-3

APPENDIX A: HIERARCHICAL CAUSE MATRIX
Order
#
20

Cause Description

Cause
Code

Open Flame

08

21

Other Equipment

Priority Cause Description

Priority
Cause Code

Torches

18

Service Equipment

19

10

22

Vehicle, Engine

20

23

Unclassified Fuel Powered
Equipment

25

Unclassified Equipment with
Other or Unknown Fuel Source

39

24

Unknown

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

13

Matrix Code Category Logic
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (fact_ign_1 = ‘13’
OR fact_ign_2 = ‘13’
OR equip_inv BETWEEN ‘331’ AND ‘334’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (equip_inv = ‘225’
OR equip_inv BETWEEN ‘228’ AND ‘229’
OR equip_inv = ‘352’
OR equip_inv = ‘354’
OR equip_inv BETWEEN ‘362’ AND ‘365’
OR equip_inv BETWEEN ‘433’ AND ‘434’)
AND LEFT(fact_ign_1,1) != ‘1’
AND LEFT(fact_ign_2,1) != ‘1’
AND LEFT(fact_ign_1,1) != ‘2’
AND LEFT(fact_ign_2,1) != ‘2’
AND LEFT(fact_ign_1,1) != ‘5’
AND LEFT(fact_ign_2,1) != ‘5’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND inc_type BETWEEN ‘110’ AND ‘129’ AND (mob_invol BETWEEN ‘2’ AND ‘3’
OR heat_sourc = ‘68’
OR equip_inv = ‘375’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc BETWEEN ‘10’ AND ‘12’
AND eq_power BETWEEN ‘10’ AND ‘49’)
AND LEFT(fact_ign_1,1) != ‘1’
AND LEFT(fact_ign_2,1) != ‘1’
AND LEFT(fact_ign_1,1) != ‘2’
AND LEFT(fact_ign_2,1) != ‘2’
AND LEFT(fact_ign_1,1) != ‘5’
AND LEFT(fact_ign_2,1) != ‘5’;
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc BETWEEN ‘10’ AND ‘12’
AND eq_power NOT BETWEEN ‘10’ AND ‘49’)
AND LEFT(fact_ign_1,1) != ‘1’
AND LEFT(fact_ign_2,1) != ‘1’
AND LEFT(fact_ign_1,1) != ‘2’
AND LEFT(fact_ign_2,1) != ‘2’
AND LEFT(fact_ign_1,1) != ‘5’
AND LEFT(fact_ign_2,1) != ‘5’

Comments

See note above for PCC 25.

A-4

APPENDIX A: HIERARCHICAL CAUSE MATRIX
Order
#

25

Cause Description

Cause
Code

Electrical Malfunction

06

26
Open Flame

Priority Cause Description

Priority
Cause Code

Unclassified Electrical Malfunction

26

Matches, Candles

27

08

27

Open Fire

28

28

Other Open Flame, Spark

29

Other Heat

09

29

Fireworks

30

30

Open Flame

08

Ember, Rekindle

31

31

Other Heat

09

Other Hot Object

32

32

Natural

11

Natural 2

06

33

Other Unintentional, Careless

15

Heat Source or Product Misuse

21

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Matrix Code Category Logic
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc = ‘13’
OR fact_ign_1 BETWEEN ‘30’ AND ‘36’
OR fact_ign_2 BETWEEN ‘30’ AND ‘36’
OR equip_inv = ‘200’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc BETWEEN ‘64’ AND ‘66’
OR (equip_inv = ‘872’
AND eq_power BETWEEN ‘20’ AND ‘39’)
OR equip_inv = ‘873’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND heat_sourc = ‘67’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc = ‘60’
OR heat_sourc = ‘69’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND heat_sourc BETWEEN ‘41’ AND ‘42’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (heat_sourc = ‘43’
OR fact_ign_1 = ‘72’
OR fact_ign_2 = ‘72’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND heat_sourc = ‘40’
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (LEFT(fact_ign_1,1) = ‘6’
OR LEFT(fact_ign_2,1) = ‘6’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (LEFT(fact_ign_1,1) = ‘1’
OR LEFT(fact_ign_2,1) = ‘1’)

Comments

PCC 26 (Unclassified Electrical Malfunction) combined into cause
category 06.

Additional ‘natural’ from Factors Contributing to Ignition.

New category from 10 series of Factors Contributing to Ignition.

A-5

APPENDIX A: HIERARCHICAL CAUSE MATRIX
Order
#

Cause Description

Cause
Code

34

Priority Cause Description
Equipment Operation Deficiency

Equipment Misoperation,
Failure

Priority
Cause Code
22

14

35

Equipment Failure, Malfunction

23

36

Unknown

13

Trash, Rubbish

37

37

Other Unintentional, Careless

15

Other Unintentional

24

38

Exposure

12

Exposure 2

33

39

Unknown

13

Unknown

34

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Matrix Code Category Logic
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (LEFT(fact_ign_1,1) = ‘5’
OR LEFT(fact_ign_2,1) = ‘5’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (LEFT(fact_ign_1,1) = ‘2’
OR LEFT(fact_ign_2,1) = ‘2’
OR cause_ign = ‘3’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (inc_type = ‘118’
OR first_ign = ‘96’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (LEFT(fact_ign_1,1) = ‘2’
OR LEFT(fact_ign_2,1) = ‘2’
OR cause_ign = ‘2’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0
AND (fact_ign_1 BETWEEN ‘70’ AND ‘71’
OR fact_ign_2 BETWEEN ‘70’ AND ‘71’
OR fact_ign_1 BETWEEN ‘73’ AND ‘75’
OR fact_ign_2 BETWEEN ‘73’ AND ‘75’
OR heat_sourc BETWEEN ‘80’ AND ‘89’)
aid NOT BETWEEN ‘3’ AND ‘4’
AND exp_no = 0

Comments

New category, includes cause of ignition ‘failure of equipment or heat
source’ as final pass.

New PCC for trash related fires.

New category, from cause of ignition ‘Unintentional’’ as final pass.

Fell through the matrix with no match.

A-6

APPENDIX B: GENERAL INCIDENT GROUPING BY INCIDENT TYPE AND PROPERTY TYPE

APPENDIX B: GENERAL INCIDENT GROUPING
BY INCIDENT TYPE AND PROPERTY USE

Note: Nonresidential is defined by being “not residential” under the assumption that a residential structure
will be clearly evident to the firefighter and the data collected as such. Generally speaking, if the property type
is not specifically noted as “residential,” it is then “nonresidential.”
Incident Type

All Fires

Outside

Property Use
(PROP_USE)

Vehicle

Structure

Residential
Structure
400 series

Nonresidential
Structure
not 400 series
excludes null
from 2006 on

Other

Null
ü*
100
ü
ü
111-118
ü
ü
ü
ü
120-123
ü
ü
ü
ü
130s, MOB_INü
ü
VOL=1, 3
130s, MOB_
INVOL=2,N,
ü
NULL
140s
ü
ü
150s
ü
ü
160s less 163
ü
ü
163
ü
ü
170-173
ü
ü
101-109
ü
180-189
Undesignated
ü
190-199
ü
*Only property uses (PROP_USE) with null values prior to 2006 are collated as “Other” properties. As property use is
required from 2006 on, property uses with a null value are considered invalid and removed from analyses.

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

B-1

APPENDIX C: NFIRS PDR FILE LAYOUTS

APPENDIX C: NFIRS PDR FILE LAYOUTS

In the file layout tables that follow, the key identification (ID) fields are noted in red text.

Basic Incident Table (basicincident.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
DEPT_STA
INC_TYPE
ADD_WILD
AID
ALARM
ARRIVAL
INC_CONT
LU_CLEAR
SHIFT
ALARMS
DISTRICT
ACT_TAK1
ACT_TAK2
ACT_TAK3
APP_MOD
SUP_APP
EMS_APP
OTH_APP

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Fire Department Station
Incident Type
Address on Wildland Flag
Aid Given or Received
Alarm Date and Time
Arrival Date and Time
Incident Controlled Date and Time
Last Unit Cleared Date and Time
Shift
Alarms
District
Actions Taken #1
Actions Taken #2
Actions Taken #3
Apparatus/Personnel Module Used
Suppression Apparatus
EMS Apparatus
Other Apparatus

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
X
C
X
C
N
N
N
N
X
X
X
C
C
C
X
N
N
N

Length
2
5
8
7
3
5
3
3
1
1
12
12
12
12
1
2
3
2
2
2
1
4
4
4

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

MMDDYYYYhhmm

C-1

Field Number
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41

.DBF Field Name
SUP_PER
EMS_PER
OTH_PER
RESOU_AID
PROP_LOSS
CONT_LOSS
PROP_VAL
CONT_VAL
FF_DEATH
OTH_DEATH
FF_INJ
OTH_INJ
DET_ALERT
HAZ_REL
MIXED_USE
PROP_USE
CENSUS

Field Name
Suppression Personnel
EMS Personnel
Other Personnel
Resources Include Mutual Aid
Property Loss
Contents Loss
Property Value
Contents Value
Fire Service Deaths
Other Fire Deaths
Fire Service Injuries
Other Fire Injuries
Detector Alerted Occupants
Hazardous Material Released
Mixed Use
Property Use
Census Tract

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
N
N
N
Y
N
N
N
N
N
N
N
N
C
C
C
C
X

Length
4
4
4
1
9
9
9
9
3
3
3
3
1
1
2
3
6

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

C-2

Basic Incident Address Table (incidentaddress.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
LOC_TYPE
NUM_MILE
STREET_PRE
STREETNAME
STREETTYPE
STREETSUF
APT_NO
CITY
STATE_ID
ZIP5
ZIP4
X_STREET

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
Location Type
Number or Milepost
Street Prefix
Street or Highway Name
Street Type
Street Suffix
Apartment Number
City
State
Zip 5
Zip 4
Cross Street or Directions

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
C
X
C
X
C
C
X
X
C
X
X
X

Length
2
5
8
7
3
1
8
2
30
4
2
15
20
2
5
4
30

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address
Incident Address

C-3

Basic Incident Aid Given or Received Table (basicaid.dbf)
Field Number
1
2
3
4
5
6
7
8
9

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
NFIR_VER
FDIDRECAID
FDIDSTREC
INC_NOFDID

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
FDID Receiving Aid
FDID State Receiving Aid
Incident Number of FDID Receiving Aid

Data Type
C
X
N
X
N
X
X
C
X

Length
2
5
8
7
3
5
5
2
7

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

Fire Incident Table (fireincident.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
NUM_UNIT
NOT_RES
BLDG_INVOL
ACRES_BURN
LESS_1ACRE
ON_SITE_M1
MAT_STOR1
ON_SITE_M2
MAT_STOR2
ON_SITE_M3

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Number of Residential Units
Not Residential Flag
Number of Buildings Involved
Acres Burned
Less Than One Acre
On Site Materials #1
Material Storage Use #1
On Site Materials #2
Material Storage Use #2
On Site Materials #3

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
N
Y
N
N
Y
C
C
C
C
C

Length
2
5
8
7
3
5
4
1
3
6
1
3
1
3
1
3

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

C-4

Field Number
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44

.DBF Field Name
MAT_STOR3
AREA_ORIG
HEAT_SOURC
FIRST_IGN
CONF_ORIG
TYPE_MAT
CAUSE_IGN
FACT_IGN_1
FACT_IGN_2
HUM_FAC_1
HUM_FAC_2
HUM_FAC_3
HUM_FAC_4
HUM_FAC_5
HUM_FAC_6
HUM_FAC_7
HUM_FAC_8
AGE
SEX
EQUIP_INV
SUP_FAC_1
SUP_FAC_2
SUP_FAC_3
MOB_INVOL
MOB_TYPE
MOB_MAKE
MOB_MODEL
MOB_YEAR

Field Name
Material Storage Use #3
Area of Origin
Heat Source
Item First Ignited
Confined To Origin
Type of Material
Cause of Ignition
Factors Contributing To Ignition #1
Factors Contributing To Ignition #2
Human Factors #1
Human Factors #2
Human Factors #3
Human Factors #4
Human Factors #5
Human Factors #6
Human Factors #7
Human Factors #8
Age of Person
Sex of Person
Equipment Involved
Suppression Factors #1
Suppression Factors #2
Suppression Factors #3
Mobile Property Involved
Mobile Property Type
Mobile Property Make
Mobile Property Model
Mobile Property Year

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
F
C
C
C
C
C
C
C
C
X
N

Length
1
2
2
2
1
2
1
2
2
1
1
1
1
1
1
1
1
3.2
1
3
3
3
3
1
2
2
25
4

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

Associated with Human Factor code 7
Associated with Human Factor code 7

4 digit year only
C-5

Field Number
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72

.DBF Field Name
MOB_LIC_PL
MOB_STATE
MOB_VIN_NO
EQ_BRAND
EQ_MODEL
EQ_SER_NO
EQ_YEAR
EQ_POWER
EQ_PORT
FIRE_SPRD
STRUC_TYPE
STRUC_STAT
BLDG_ABOVE
BLDG_BELOW
BLDG_LGTH
BLDG_WIDTH
TOT_SQ_FT
FIRE_ORIG
ST_DAM_MIN
ST_DAM_SIG
ST_DAM_HVY
ST_DAM_XTR
FLAME_SPRD
ITEM_SPRD
MAT_SPRD
DETECTOR
DET_TYPE
DET_POWER

Field Name
Mobile Property License Plate
Mobile Property State
Mobile Property VIN Number
Equipment Brand
Equipment Model
Equipment Serial Number
Equipment Year
Equipment Power
Equipment Portability
Fire Spread
Structure Type
Structure Status
Building Height: Stories Above Grade
Building Height: Stories Below Grade
Building Length
Building Width
Total Square Feet
Fire Origin
Number of Stories with Damage: Minor
Number of Stories with Damage: Significant
Number of Stories with Damage: Heavy
Number of Stories with Damage: Extreme
No Flame Spread/Same As First/Unknown
Item Contributing Most to Spread
Type Material Contributing Most To Spread
Detector Presence
Detector Type
Detector Power

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
X
C
X
X
X
X
N
C
C
C
C
C
N
N
N
N
N
N
N
N
N
N
Y
C
C
C
C
C

Length
10
2
17
25
25
25
4
2
1
1
1
1
3
2
4
4
8
3
3
3
3
3
1
2
2
1
1
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

4 digit year only

Beginning of Structure Fire Information

+ or -, negative numbers indicate below grade

C-6

Field Number
73
74
75
76
77
78
79
80

.DBF Field Name
DET_OPERAT
DET_EFFECT
DET_FAIL
AES_PRES
AES_TYPE
AES_OPER
NO_SPR_OP
AES_FAIL

Field Name
Detector Operation
Detector Effectiveness
Detector Failure Reason
AES Presence
AES Type
AES Operation
Number of Sprinklers Operating
AES Failure Reason

Data Type
C
C
C
C
C
C
N
C

Length
1
1
1
1
1
1
3
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

Civilian Fire Casualty Table (civiliancasualty.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
SEQ_NUMBER
VERSION
GENDER
AGE
RACE
ETHNICITY
AFFILIAT
INJ_DT_TIM
SEV
CAUSE_INJ
HUM_FACT1
HUM_FACT2
HUM_FACT3

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
Civilian Fire Casualty Sequence Number
NFIRS Data Version
Gender
Age
Race
Ethnicity
Affiliation
Injury Date and Time
Severity
Cause of Injury
Human Factor Contributing to Injury #1
Human Factor Contributing to Injury #2
Human Factor Contributing to Injury #3

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
N
X
C
F
C
C
C
N
C
C
C
C
C

Length
2
5
8
7
3
3
5
1
3.2
1
1
1
12
1
1
1
1
1

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

MMDDYYYYhhmm

C-7

Field Number
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35

.DBF Field Name
HUM_FACT4
HUM_FACT5
HUM_FACT6
HUM_FACT7
HUM_FACT8
FACT_INJ1
FACT_INJ2
FACT_INJ3
ACTIV_INJ
LOC_INC
GEN_LOC_IN
STORY_INC
STORY_INJ
SPC_LOC_IN
PRIM_SYMP
BODY_PART
CC_DISPOS

Field Name
Human Factor Contributing to Injury #4
Human Factor Contributing to Injury #5
Human Factor Contributing to Injury #6
Human Factor Contributing to Injury #7
Human Factor Contributing to Injury #8
Factors Contributing to Injury #1
Factors Contributing to Injury #2
Factors Contributing to Injury #3
Activity When Injured
Location at Time of Incident
General Location at Time of Injury
Story at Start of Incident
Story Where Injury Occurred
Specific Location at Time of Injury
Primary Apparent Symptom
Primary Part of Body Injured
Disposition

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
C
C
C
C
C
C
C
C
C
C
N
N
C
C
C
C

Length
1
1
1
1
1
2
2
2
1
1
1
3
3
2
2
1
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

+ or -, negative numbers indicate below grade
+ or -, negative numbers indicate below grade

C-8

Fire Service Casualty Table (ffcasualty.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
FF_SEQ_NO
VERSION
GENDER
CAREER
AGE
INJ_DATE
RESPONSES
ASSIGNMENT
PHYS_COND
SEVERITY
TAKEN_TO
ACTIVITY
SYMPTOM
PABI
CAUSE
FACTOR
OBJECT
WIO
RELATION
STORY
LOCATION
VEHICLE
PROT_EQP

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
Fire Service Casualty Sequence Number
NFIRS Data Version
Gender
Career
Age
Injury Date and Time
Responses
Usual Assignment
Physical Condition
Severity
Taken to
Activity at Time of Injury
Primary Apparent Symptom
Primary Area of Body Injured
Cause of Firefighter Injury
Factor Contributing to Injury
Object Involved in Injury
Where Injury Occurred
Injury Relation to Structure
Story of Injury
Specific Location
Vehicle Type
Protective Equipment Contributed to Injury

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
N
X
C
C
N
N
N
C
C
C
C
C
C
C
C
C
C
C
C
N
C
C
C

APPENDIX C: NFIRS PDR FILE LAYOUTS

Length
2
5
8
7
3
3
5
1
1
3
12
2
1
1
1
1
2
2
2
1
2
2
1
1
3
2
1
1

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

MMDDYYYYhhmm

+ or -, negative numbers indicate below grade

C-9

Fire Service Equipment Failure Table (ffequipfail.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
CAS_SEQ_NO
EQP_SEQ_NO
VERSION
EQUIP_ITEM
EQP_PROB
EQP_MAN
EQP_MOD
EQP_SER_NO

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
Fire Service Casualty Sequence Number
Equipment Failure Sequence Number
NFIRS Data Version
Equipment Item
Equipment Problem
Equipment Manufacturer
Equipment Model
Equipment Serial Number

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
N
N
X
C
C
X
X
X

Length
2
5
8
7
3
3
3
5
2
2
12
12
12

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

C-10

APPENDIX C: NFIRS PDR FILE LAYOUTS

Wildland Fire Table (wildlands.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
LATITUDE
LONGITUDE
TOWNSHIP
NORTH_SOU
RANGE
EAST_WEST
SECTION
SUBSECTION
MERIDIAN
AREA_TYPE
FIRE_CAUSE
HUM_FACT1
HUM_FACT2
HUM_FACT3
HUM_FACT4
HUM_FACT5
HUM_FACT6
HUM_FACT7
HUM_FACT8
FACT_IGN1
FACT_IGN2
SUPP_FACT1

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Latitude
Longitude
Township
North/South
Range
East/West
Section
Subsection
Meridian
Area Type
Wildland Fire Cause
Human Factors Contributing #1
Human Factors Contributing #2
Human Factors Contributing #3
Human Factors Contributing #4
Human Factors Contributing #5
Human Factors Contributing #6
Human Factors Contributing #7
Human Factors Contributing #8
Factors Contributing to Ignition #1
Factors Contributing to Ignition #2
Fire Suppression Factors #1

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
F
F
F
C
N
C
N
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
2
5
8
7
3
5
2.2
3.2
3.1
1
3
1
2
4
2
1
1
1
1
1
1
1
1
1
1
2
2
3

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

C-11

Field Number
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56

.DBF Field Name
SUPP_FACT2
SUPP_FACT3
HEAT_SOURC
MOB_PROP
EQ_INV_IGN
NFDRS_ID
WEATH_TYPE
WIND_DIR
WIND_SPEED
AIR_TEMP
REL_HUMID
FUEL_MOIST
DANGR_RATE
BLDG_INV
BLDG_THR
ACRES_BURN
CROP_BURN1
CROP_BURN2
CROP_BURN3
UNDET_BURN
TAX_BURN
NOTAX_BURN
LOCAL_BURN
COUTY_BURN
ST_BURN
FED_BURN
FOREI_BURN
MILIT_BURN

Field Name
Fire Suppression Factors #2
Fire Suppression Factors #3
Heat Source
Mobile Property Type
Equipment Involved In Ignition
NFDRS Weather Station ID
Weather Type
Wind Direction
Wind Speed
Air Temperature
Relative Humidity
Fuel Moisture
Fire Danger Rating
Number of Buildings Involved
Number of Buildings Threatened
Total Acres Burned
Primary Crop Burned 1
Primary Crop Burned 2
Primary Crop Burned 3
Undetermined Acres Burned %
Tax Paying Acres Burned %
Non-Tax Paying Acres Burned %
City, Town, Village, Local Acres Burned %
County or parish Acres Burned %
State or province Acres Burned %
Federal Acres Burned %
Foreign Acres Burned %
Military Acres Burned %

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
C
C
C
C
A
C
C
N
N
N
N
C
N
N
F
X
X
X
N
N
N
N
N
N
N
N
N

Length
3
3
2
2
3
6
2
1
3
3
3
2
1
3
3
9.1
25
25
25
3
3
3
3
3
3
3
3
3

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

+ or -

C-12

Field Number
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71

.DBF Field Name
OTHER_BURN
PROP_MANAG
FED_CODE
NFDRS_FM
PERSON_FIR
GENDER
AGE
ACTIVITY_W
HORIZ_DIS
TYPE_ROW
ELEVATION
POS_SLOPE
ASPECT
FLAME_LGTH
SPREAD_RAT

Field Name
Other Acres Burned %
Property Management Ownership
Federal Agency Code
NFDRS Fuel Model at Origin
Person Responsible for Fire
Gender
Age
Activity of Person
Horizontal Distance From ROW
Type of ROW
Elevation
Relative Position on Slope
Aspect
Flame Length
Rate of Spread

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
N
C
X
C
C
C
F
C
N
C
N
C
C
N
N

Length
3
1
5
2
1
1
3.2
2
2
3
5
1
1
2
3

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

C-13

APPENDIX C: NFIRS PDR FILE LAYOUTS

EMS Table (ems.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
PATIENT_NO
VERSION
ARRIVAL
TRANSPORT
PROVIDER_A
AGE
GENDER
RACE
ETH_EMS
HUM_FACT1
HUM_FACT2
HUM_FACT3
HUM_FACT4
HUM_FACT5
HUM_FACT6
HUM_FACT7
HUM_FACT8
OTHER_FACT
SITE_INJ1
SITE_INJ2
SITE_INJ3
SITE_INJ4
SITE_INJ5

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
EMS Patient Sequence Number
NFIRS Data Version
Arrived at Patient Date and Time
Patient Transfer Date and Time
Provider Impression/Assessment
Age
Gender
Race
Ethnicity
Human Factors #1
Human Factors #2
Human Factors #3
Human Factors #4
Human Factors #5
Human Factors #6
Human Factors #7
Human Factors #8
Other Factors
Body Sites of Injury #1
Body Sites of Injury #2
Body Sites of Injury #3
Body Sites of Injury #4
Body Sites of Injury #5

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
N
X
N
N
C
F
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
2
5
8
7
3
3
5
12
12
2
3.2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Key Field
Data Version (converted 4.1 or 5.0)
MMDDYYYYhhmm
MMDDYYYYhhmm

C-14

Field Number
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57

.DBF Field Name
INJ_TYPE1
INJ_TYPE2
INJ_TYPE3
INJ_TYPE4
INJ_TYPE5
CAUSE_ILL
PROC_USE1
PROC_USE2
PROC_USE3
PROC_USE4
PROC_USE5
PROC_USE6
PROC_USE7
PROC_USE8
PROC_USE9
PROC_USE10
PROC_USE11
PROC_USE12
PROC_USE13
PROC_USE14
PROC_USE15
PROC_USE16
PROC_USE17
PROC_USE18
PROC_USE19
PROC_USE20
PROC_USE21
PROC_USE22
PROC_USE23

Field Name
Injury Types #1
Injury Types #2
Injury Types #3
Injury Types #4
Injury Types #5
Cause of Illness/Injury
Procedures Used #1
Procedures Used #2
Procedures Used #3
Procedures Used #4
Procedures Used #5
Procedures Used #6
Procedures Used #7
Procedures Used #8
Procedures Used #9
Procedures Used #10
Procedures Used #11
Procedures Used #12
Procedures Used #13
Procedures Used #14
Procedures Used #15
Procedures Used #16
Procedures Used #17
Procedures Used #18
Procedures Used #19
Procedures Used #20
Procedures Used #21
Procedures Used #22
Procedures Used #23

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

C-15

Field Number
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76

.DBF Field Name
PROC_USE24
PROC_USE25
SAFE_EQP1
SAFE_EQP2
SAFE_EQP3
SAFE_EQP4
SAFE_EQP5
SAFE_EQP6
SAFE_EQP7
SAFE_EQP8
ARREST
ARR_DES1
ARR_DES2
AR_RHYTHM
IL_CARE
HIGH_CARE
PAT_STATUS
PULSE
EMS_DISPO

Field Name
Procedures Used #24
Procedures Used #25
Safety Equipment Used #1
Safety Equipment Used #2
Safety Equipment Used #3
Safety Equipment Used #4
Safety Equipment Used #5
Safety Equipment Used #6
Safety Equipment Used #7
Safety Equipment Used #8
Pre or Post Arrival Arrest
Pre-Arrival Arrest Descriptors #1
Pre-Arrival Arrest Descriptors #2
Initial Arrest Rhythm
Initial Level of Care
Highest Level of Care
Patient Status
Pulse on Transfer
Disposition

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

C-16

Hazardous Material Table (hazmat.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
REL_FROM
REL_STORY
POP_DENS
AFFEC_MEAS
AFFEC_UNIT
EVAC_MEAS
EVAC_UNIT
PEOP_EVAC
BLDG_EVAC
HAZ_ACT1
HAZ_ACT2
HAZ_ACT3
OCCUR_FIRS
CAUSE_REL
FACT_REL1
FACT_REL2
FACT_REL3
MIT_FACT1
MIT_FACT2
MIT_FACT3
EQ_INV_REL
HAZ_DISPO

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Released From
Story of Release
Population Density
Area Affected Measurement
Area Affected Units
Area Evacuated Measurement
Area Evacuated Units
Estimated Number of People Evacuated
Estimated Number of Buildings Evacuated
Hazmat Actions Taken #1
Hazmat Actions Taken #2
Hazmat Actions Taken #3
Occurred First
Cause of Release
Factors Contributing to Release #1
Factors Contributing to Release #2
Factors Contributing to Release #3
Mitigating Factors #1
Mitigating Factors #2
Mitigating Factors #3
Equipment Involved in Release
Disposition

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
C
N
C
N
C
N
C
N
N
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
2
5
8
7
3
5
1
3
1
4
1
4
1
6
4
2
2
2
1
1
2
2
2
2
2
2
3
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)
+ or -, negative numbers indicate below grade

C-17

Field Number .DBF Field Name
29
HAZ_DEATH
30
HAZ_INJ

Field Name
Hazmat Civilian Deaths
Hazmat Civilian Injuries

Data Type
N
N

Length
4
4

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

Hazardous Material Chemical Table (hazchem.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
SEQ_NUMBER
VERSION
UN_NUMBER
DOT_CLASS
CAS_REGIS
CHEM_NAME
CONT_TYPE
CONT_CAP
CAP_UNIT
AMOUNT_REL
UNITS_REL
PHYS_STATE
REL_INTO

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
Hazmat Chemical Sequence Number
NFIRS Data Version
UN Number
DOT Hazard Classification
CAS Registration
Chemical Name
Container Type
Estimated Container Capacity
Capacity Units
Estimated Amount Released
Released Units
Physical State When Released
Released Into

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
N
X
X
C
X
X
C
N
C
N
C
C
C

Length
2
5
8
7
3
2
5
4
2
10
50
2
9
2
9
2
1
1

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

C-18

Hazardous Material Mobile Property Type Table (hazmobprop.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
MP_TYPE
MP_MAKE
MP_MODEL
MP_YEAR
MP_LICENSE
MP_STATE
MP_DOT_ICC

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Mobile Property Type
Mobile Property Make
Mobile Property Model
Mobile Property Year
Mobile Property License Plate
Mobile Property State
Mobile Property DOT/ICC Number

Data Type
C
X
N
X
N
X
C
C
X
N
X
C
X

Length
2
5
8
7
3
5
2
2
25
4
10
2
17

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

4 digit year only

Hazardous Material Equipment Involved Table (hazmatequipinvolved.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
EQ_BRAND
EQ_MODEL
EQ_SER_NO
EQ_YEAR

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Equipment Brand
Equipment Model
Equipment Serial Number
Equipment Year

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
X
X
X
N

Length
2
5
8
7
3
5
25
25
25
4

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

4 digit year only

C-19

APPENDIX C: NFIRS PDR FILE LAYOUTS

Arson Table (arson.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
CASE_STAT
AVAIL_MFI
MOT_FACTS1
MOT_FACTS2
MOT_FACTS3
GRP_INVOL1
GRP_INVOL2
GRP_INVOL3
ENTRY_METH
EXT_FIRE
DEVI_CONT
DEVI_IGNIT
DEVI_FUEL
INV_INFO1
INV_INFO2
INV_INFO3
INV_INFO4
INV_INFO5
INV_INFO6
INV_INFO7
INV_INFO8
PROP_OWNER

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Case Status
Availability of Material First Ignited
Suspected Motivation Factors #1
Suspected Motivation Factors #2
Suspected Motivation Factors #3
Apparent Group Involvement #1
Apparent Group Involvement #2
Apparent Group Involvement #3
Entry Method
Extent of Fire Involvement on Arrival
Incendiary Devices: Container
Incendiary Devices: Ignition/Delay Device
Incendiary Devices: Fuel
Other Investigative Information #1
Other Investigative Information #2
Other Investigative Information #3
Other Investigative Information #4
Other Investigative Information #5
Other Investigative Information #6
Other Investigative Information #7
Other Investigative Information #8
Property Ownership

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
2
5
8
7
3
5
1
1
2
2
2
1
1
1
2
1
2
2
2
1
1
1
1
1
1
1
1
1

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

C-20

Field Number
29
30
31
32
33
34
35
36
37
38
39
40
41
42

.DBF Field Name
INIT_OB1
INIT_OB2
INIT_OB3
INIT_OB4
INIT_OB5
INIT_OB6
INIT_OB7
INIT_OB8
LAB_USED1
LAB_USED2
LAB_USED3
LAB_USED4
LAB_USED5
LAB_USED6

Field Name
Initial Observations #1
Initial Observations #2
Initial Observations #3
Initial Observations #4
Initial Observations #5
Initial Observations #6
Initial Observations #7
Initial Observations #8
Laboratory Used #1
Laboratory Used #2
Laboratory Used #3
Laboratory Used #4
Laboratory Used #5
Laboratory Used #6

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
1
1
1
1
1
1
1
1
1
1
1
1
1
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments

C-21

APPENDIX C: NFIRS PDR FILE LAYOUTS

Arson Agency Referral Table (arsonagencyreferal.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
AGENCY_NAM
VERSION
AG_ST_NUM
AG_ST_PREF
AG_STREET
AG_ST_TYPE
AG_ST_SUFF
AG_APT_NO
AG_CITY
AG_STATE
AG_ZIP5
AG_ZIP4
AG_PHONE
AG_CASE_NO
AG_ORI
AG_FID
AG_FDID

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
Agency Name
NFIRS Data Version
Agency Street Number
Agency Street Prefix
Agency Street or Highway
Agency Street Type
Agency Street Suffix
Agency Apartment Number
Agency City
Agency State
Agency ZIP 5 Code
Agency ZIP 4 Code
Agency Phone Number
Agency Case Number
Agency ORI
Agency FID
Agency FDID

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
X
X
C
X
C
C
X
X
C
X
X
N
X
X
X
X

Length
2
5
8
7
3
30
5
8
2
30
4
2
15
20
2
5
4
10
12
5
2
5

Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

1st 5 of Zip
Last 4 of Zip

C-22

Arson Juvenile Subject Table (arsonjuvsub.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
SUB_SEQ_NO
VERSION
AGE
GENDER
RACE
ETHNICITY
FAM_TYPE
RISK_FACT1
RISK_FACT2
RISK_FACT3
RISK_FACT4
RISK_FACT5
RISK_FACT6
RISK_FACT7
RISK_FACT8
JUV_DISPO

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
Subject Sequence Number
NFIRS Data Version
Age
Gender
Race
Ethnicity
Family Type
Motivation/Risk Factors #1
Motivation/Risk Factors #2
Motivation/Risk Factors #3
Motivation/Risk Factors #4
Motivation/Risk Factors #5
Motivation/Risk Factors #6
Motivation/Risk Factors #7
Motivation/Risk Factors #8
Disposition

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
N
X
N
C
C
C
C
C
C
C
C
C
C
C
C
C

Length
2
5
8
7
3
3
5
3
1
1
1
1
1
1
1
1
1
1
1
1
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Key Field
Data Version (converted 4.1 or 5.0)

C-23

APPENDIX C: NFIRS PDR FILE LAYOUTS

Fire Department Header Table (fdheader.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

.DBF Field Name
STATE
FDID
FD_NAME
FD_STR_NO
FD_STR_PRE
FD_STREET
FD_STR_TYP
FD_STR_SUF
FD_CITY
FD_ZIP
FD_PHONE
FD_FAX
FD_EMAIL
FD_FIP_CTY
NO_STATION
NO_PD_FF
NO_VOL_FF
NO_VOL_PDC

Field Name
Fire Dept. State
Fire Dept. ID
Fire Department Name
Fire Department Street Number of Milepost
Fire Department Street Prefix
Fire Department Street or Highway Name
Fire Department Street Type
Fire Department Street Suffix
Fire Department City
Fire Department Zip
Fire Department Phone
Fire Department Fax
Fire Department E-mail
Fire Department FIPS County Code
Number of Stations
Number of Paid Firefighters
Number of Volunteer Firefighters
Number of Volunteer Paid Per Call

Data Type
C
X
X
X
C
X
C
C
X
X
N
N
X
X
N
N
N
N

Length
2
5
30
8
2
30
4
2
20
9
10
10
45
3
3
4
4
4

Comments
Key Field
Key Field

Code Descriptor Lookup Table (codelookup.dbf)
Field Number .DBF Field Name
1
FIELDID
2
CODE_VALUE
3
CODE_DESCR

Field Name
FIELDID
Code Value
Code Descriptor

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
X
C
X

Length
25
4
50

Comments
Key Field

C-24

NFIRS 4.1 Legacy Field Table (legacyfields.dbf)
Field Number
1
2
3
4
5
6
7
8
9
10
11
12
13

.DBF Field Name
STATE
FDID
INC_DATE
INC_NO
EXP_NO
VERSION
METH_ALARM
METH_EXTIN
CONST_TYPE
SMOKE_DAM
TYPE_MSMOK
FORM_MSMOK
AVE_SMKTRV

Field Name
Fire Dept. State
Fire Dept. ID
Incident Date
Incident Number
Exposure Number
NFIRS Data Version
Method of Alarm
Method of Extinguishment
Construction Type
Extent of Smoke Damage
Type Material Generating Most Smoke
Form of Material Generating Most Smoke
Avenue of Smoke Travel

NFIRS 5.0 Fire Data Analysis Guidelines and Issues

Data Type
C
X
N
X
N
X
C
C
C
C
C
C
C

Length
2
5
8
7
3
5
1
1
1
1
2
2
1

APPENDIX C: NFIRS PDR FILE LAYOUTS
Comments
Key Field
Key Field
Key Field (MMDDYYYY)
Key Field
Key Field
Data Version (converted 4.1 or 5.0)
NFIRS 4.1 legacy field
NFIRS 4.1 legacy field
NFIRS 4.1 legacy field
NFIRS 4.1 legacy field
NFIRS 4.1 legacy field
NFIRS 4.1 legacy field
NFIRS 4.1 legacy field

C-25