29 Cfr 1910.1028

§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

3.7.3. The μg/mL creatinine from section
3.7.2. is then multiplied by 100 (the dilution factor). This value is equivalent to
the micrograms of creatinine in the 1.0
mL stabilized urine aliquot or the milligrams of creatinine per liter of urine.
The desired units, g/L, is determined by
the following relationship:

3.7.4. The resulting value for creatinine is
used to normalize the urinary concentration of the desired analyte (A) (Cd or
B2M) by using the following formula.

μg A/L (experimental)
g/L creatinine

3.8. Safety precautions See section 2.7.
4. Conclusions
The determination of creatinine in urine
by HPLC is a good alternative to the Jaffe
method for industrial hygiene laboratories.
Sample clarification with SEP-PAKs did not
change the amount of creatinine found in
urine samples. However, it does protect the
analytical column. The results of this creatinine in urine procedure are unaffected by the
pH of the urine sample under the conditions
tested by this procedure. Therefore, no special measures are required for creatinine
analysis whether the urine sample has been
stabilized with 10% nitric acid for the Cd
analysis or brought to a pH of 7 with 0.11 N
NaOH for the B2M analysis.
5. References
5.1. Clark, L.C.; Thompson, H.L.; Anal. Chem.
1949, 21, 1218.
5.2. Peters, J.H.; J. Biol. Chem. 1942, 146, 176.
5.3. Hausen, V.A.; Fuchs, D.; Wachter, H.; J.
Clin. Chem. Clin. Biochem. 1981, 19, 373–378.
5.4. Clark, P.M.S.; Kricka L.J.; Patel, A.; J.
Liq. Chrom. 1980, 3(7), 1031–1046.
5.5. Ballerini, R.; Chinol, M.; Cambi, A.; J.
Chrom. 1979, 179, 365–369.
5.6. Ogata, M.; Taguchi, T.; Industrial Health
1987, 25, 225–228.
5.7. ‘‘Merck Index’’, 11th ed.; Windholz, Martha Ed.; Merck: Rahway, N.J., 1989; p 403.
5.8. Kimberly, M.; ‘‘Determination of Cadmium
in Urine by Graphite Furnace Atomic Absorption Spectrometry with Zeeman Background Correction.’’, Centers for Disease
Control, Atlanta, Georgia, unpublished,
update 1990.
[57 FR 42389, Sept. 14, 1992, as amended at 57
FR 49272, Oct. 30, 1992; 58 FR 21781, Apr. 23,
1993; 61 FR 5508, Feb. 13, 1996; 63 FR 1288, Jan.
8, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16672,
16673, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006;
73 FR 75585, Dec. 12, 2008]

§ 1910.1028

Benzene.

(a) Scope and application. (1) This section applies to all occupational exposures to benzene. Chemical Abstracts
Service Registry No. 71–43–2, except as
provided in paragraphs (a)(2) and (a)(3)
of this section.
(2) This section does not apply to:
(i) The storage, transportation, distribution, dispensing, sale or use of
gasoline, motor fuels, or other fuels
containing benzene subsequent to its
final discharge from bulk wholesale
storage facilities, except that operations where gasoline or motor fuels
are dispensed for more than 4 hours per
day in an indoor location are covered
by this section.
(ii) Loading and unloading operations
at bulk wholesale storage facilities
which use vapor control systems for all
loading and unloading operations, except for the provisions of 29 CFR
1910.1200 as incorporated into this section and the emergency provisions of
paragraphs (g) and (i)(4) of this section.
(iii) The storage, transportation, distribution or sale of benzene or liquid
mixtures containing more than 0.1 percent benzene in intact containers or in
transportation pipelines while sealed
in such a manner as to contain benzene
vapors or liquid, except for the provisions of 29 CFR 1910.1200 as incorporated into this section and the emergency provisions of paragraphs (g) and
(i)(4) of this section.
(iv) Containers and pipelines carrying
mixtures with less than 0.1 percent
benzene and natural gas processing
plants processing gas with less than 0.1
percent benzene.

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Where A is the desired analyte. The protocol
of reporting such normalized results is μg A/
g creatinine.

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μg/mL mg/L
=
1000
1000

EC15NO91.190

μg A/g creatinine =

g/L =

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Occupational Safety and Health Admin., Labor
(v) Work operations where the only
exposure to benzene is from liquid mixtures containing 0.5 percent or less of
benzene by volume, or the vapors released from such liquids until September 12, 1988; work operations where
the only exposure to benzene is from
liquid mixtures containing 0.3 percent
or less of benzene by volume or the vapors released from such liquids from
September 12, 1988, to September 12,
1989; and work operations where the
only exposure to benzene is from liquid
mixtures containing 0.1 percent or less
of benzene by volume or the vapors released from such liquids after September 12, 1989; except that tire building machine operators using solvents
with more than 0.1 percent benzene are
covered by paragraph (i) of this section.
(vi) Oil and gas drilling, production
and servicing operations.
(vii) Coke oven batteries.
(3) The cleaning and repair of barges
and tankers which have contained benzene are excluded from paragraph (f)
methods of compliance, paragraph
(e)(1) exposure monitoring-general, and
paragraph (e)(6) accuracy of monitoring. Engineering and work practice
controls shall be used to keep exposures below 10 ppm unless it is proven
to be not feasible.
(b) Definitions. Action level means an
airborne concentration of benzene of
0.5 ppm calculated as an 8-hour timeweighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person
specifically authorized by the employer
whose duties require the person to
enter a regulated area, or any person
entering such an area as a designated
representative of employees for the
purpose of exercising the right to observe monitoring and measuring procedures under paragraph (l) of this section, or any other person authorized by
the Act or regulations issued under the
Act.
Benzene (C6 H6) (CAS Registry No. 71–
43–2) means liquefied or gaseous benzene. It includes benzene contained in
liquid mixtures and the benzene vapors
released by these liquids. It does not

§ 1910.1028

include trace amounts of unreacted
benzene contained in solid materials.
Bulk wholesale storage facility means a
bulk terminal or bulk plant where fuel
is stored prior to its delivery to wholesale customers.
Container means any barrel, bottle,
can, cylinder, drum, reaction vessel,
storage tank, or the like, but does not
include piping systems.
Day means any part of a calendar
day.
Director means the Director of the
National Institute for Occupational
Safety and Health, U.S. Department of
Health and Human Services, or designee.
Emergency means any occurrence
such as, but not limited to, equipment
failure, rupture of containers, or failure of control equipment which may or
does result in an unexpected significant release of benzene.
Employee exposure means exposure to
airborne benzene which would occur if
the employee were not using respiratory protective equipment.
Regulated area means any area where
airborne concentrations of benzene exceed or can reasonably be expected to
exceed, the permissible exposure limits, either the 8-hour time weighted average exposure of 1 ppm or the shortterm exposure limit of 5 ppm for 15
minutes.
Vapor control system means any equipment used for containing the total vapors displaced during the loading of
gasoline, motor fuel or other fuel tank
trucks and the displacing of these vapors through a vapor processing system
or balancing the vapor with the storage
tank. This equipment also includes systems containing the vapors displaced
from the storage tank during the unloading of the tank truck which balance the vapors back to the tank
truck.
(c) Permissible exposure limits (PELs)—
(1) Time-weighted average limit (TWA).
The employer shall assure that no employee is exposed to an airborne concentration of benzene in excess of one
part of benzene per million parts of air
(1 ppm) as an 8-hour time-weighted average.

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§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

(2) Short-term exposure limit (STEL).
The employer shall assure that no employee is exposed to an airborne concentration of benzene in excess of five
(5) ppm as averaged over any 15 minute
period.
(d) Regulated areas. (1) The employer
shall establish a regulated area wherever the airborne concentration of benzene exceeds or can reasonably be expected to exceed the permissible exposure limits, either the 8-hour time
weighted average exposure of 1 ppm or
the short-term exposure limit of 5 ppm
for 15 minutes.
(2) Access to regulated areas shall be
limited to authorized persons.
(3) Regulated areas shall be determined from the rest of the workplace
in any manner that minimizes the
number of employees exposed to benzene within the regulated area.
(e) Exposure monitoring—(1) General.
(i) Determinations of employee exposure shall be made from breathing zone
air samples that are representative of
each employee’s average exposure to
airborne benzene.
(ii) Representative 8-hour TWA employee exposures shall be determined
on the basis of one sample or samples
representing the full shift exposure for
each job classification in each work
area.
(iii) Determinations of compliance
with the STEL shall be made from 15
minute employee breathing zone samples measured at operations where
there is reason to believe exposures are
high, such as where tanks are opened,
filled, unloaded or gauged; where containers or process equipment are
opened and where benzene is used for
cleaning or as a solvent in an uncontrolled situation. The employer may
use objective data, such as measurements from brief period measuring devices, to determine where STEL monitoring is needed.
(iv) Except for initial monitoring as
required under paragraph (e)(2) of this
section, where the employer can document that one shift will consistently
have higher employee exposures for an
operation, the employer shall only be
required to determine representative
employee exposure for that operation
during the shift on which the highest
exposure is expected.

(2) Initial monitoring. (i) Each employer who has a place of employment
covered under paragraph (a)(1) of this
section shall monitor each of these
workplaces and work operations to determine accurately the airborne concentrations of benzene to which employees may be exposed.
(ii) The initial monitoring required
under paragraph (e)(2)(i) of this section
shall be completed by 60 days after the
effective date of this standard or within 30 days of the introduction of benzene into the workplace. Where the employer has monitored within one year
prior to the effective date of this standard and the monitoring satisfies all
other requirements of this section, the
employer may rely on such earlier
monitoring results to satisfy the requirements of paragraph (e)(2)(i) of this
section.
(3) Periodic monitoring and monitoring
frequency. (i) If the monitoring required
by paragraph (e)(2)(i) of this section reveals employee exposure at or above
the action level but at or below the
TWA, the employer shall repeat such
monitoring for each such employee at
least every year.
(ii) If the monitoring required by
paragraph (e)(2)(i) of this section reveals employee exposure above the
TWA, the employer shall repeat such
monitoring for each such employee at
least every six (6) months.
(iii) The employer may alter the
monitoring schedule from every six
months to annually for any employee
for whom two consecutive measurements taken at least 7 days apart indicate that the employee exposure has
decreased to the TWA or below, but is
at or above the action level.
(iv) Monitoring for the STEL shall be
repeated as necessary to evaluate exposures of employees subject to short
term exposures.
(4) Termination of monitoring. (i) If the
initial monitoring required by paragraph (e)(2)(i) of this section reveals
employee exposure to be below the action level the employer may discontinue the monitoring for that employee, except as otherwise required by
paragraph (e)(5) of this section.
(ii) If the periodic monitoring required by paragraph (e)(3) of this section reveals that employee exposures,

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Occupational Safety and Health Admin., Labor
as indicated by at least two consecutive measurements taken at least 7
days apart, are below the action level
the employer may discontinue the
monitoring for that employee, except
as otherwise required by paragraph
(e)(5).
(5) Additional monitoring. (i) The employer shall institute the exposure
monitoring required under paragraphs
(e)(2) and (e)(3) of this section when
there has been a change in the production, process, control equipment, personnel or work practices which may result in new or additional exposures to
benzene, or when the employer has any
reason to suspect a change which may
result in new or additional exposures.
(ii) Whenever spills, leaks, ruptures
or other breakdowns occur that may
lead to employee exposure, the employer shall monitor (using area or personal sampling) after the cleanup of
the spill or repair of the leak, rupture
or other breakdown to ensure that exposures have returned to the level that
existed prior to the incident.
(6) Accuracy of monitoring. Monitoring
shall be accurate, to a confidence level
of 95 percent, to within plus or minus
25 percent for airborne concentrations
of benzene.
(7) Employee notification of monitoring
results. (i) The employer must, within
15 working days after the receipt of the
results of any monitoring performed
under this section, notify each affected
employee of these results either individually in writing or by posting the
results in an appropriate location that
is accessible to employees.
(ii) Whenever the PELs are exceeded,
the written notification required by
paragraph (e)(7)(i) of this section shall
contain the corrective action being
taken by the employer to reduce the
employee exposure to or below the
PEL, or shall refer to a document
available to the employee which states
the corrective actions to be taken.
(f) Methods of compliance—(1) Engineering controls and work practices. (i)
The employer shall institute engineering controls and work practices to reduce and maintain employee exposure
to benzene at or below the permissible
exposure limits, except to the extent
that the employer can establish that
these controls are not feasible or where

§ 1910.1028

the provisions of paragraph (f)(1)(iii) or
(g)(1) of this section apply.
(ii) Wherever the feasible engineering
controls and work practices which can
be instituted are not sufficient to reduce employee exposure to or below the
PELs, the employer shall use them to
reduce employee exposure to the lowest
levels achievable by these controls and
shall supplement them by the use of
respiratory protection which complies
with the requirements of paragraph (g)
of this section.
(iii) Where the employer can document that benzene is used in a workplace less than a total of 30 days per
year, the employer shall use engineering controls, work practice controls or
respiratory protection or any combination of these controls to reduce employee exposure to benzene to or below
the PELs, except that employers shall
use engineering and work practice controls, if feasible, to reduce exposure to
or below 10 ppm as an 8-hour TWA.
(2) Compliance program. (i) When any
exposures are over the PEL, the employer shall establish and implement a
written program to reduce employee
exposure to or below the PEL primarily by means of engineering and
work practice controls, as required by
paragraph (f)(1) of this section.
(ii) The written program shall include a schedule for development and
implementation of the engineering and
work practice controls. These plans
shall be reviewed and revised as appropriate based on the most recent exposure monitoring data, to reflect the
current status of the program.
(iii) Written compliance programs
shall be furnished upon request for examination and copying to the Assistant Secretary, the Director, affected
employees and designated employee
representatives.
(g) Respiratory protection—(1) General.
For employees who use respirators required by this section, the employer
must provide each employee an appropriate respirator that complies with
the requirements of this paragraph.
Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering and workpractice controls.
(ii) Work operations for which the
employer establishes that compliance

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§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

with either the TWA or STEL through
the use of engineering and work-practice controls is not feasible; for example, some maintenance and repair activities, vessel cleaning, or other operations for which engineering and workpractice controls are infeasible because
exposures are intermittent and limited
in duration.
(iii) Work operations for which feasible engineering and work-practice
controls are not yet sufficient, or are
not required under paragraph (f)(1)(iii)
of this section, to reduce employee exposure to or below the PELs.
(iv) Emergencies.
(2) Respirator program. (i) The employer must implement a respiratory
protection program in accordance with
§ 1910.134(b)
through
(d)
(except
(d)(1)(iii), (d)(3)(iii)(b)(1) and (2)), and
(f) through (m), which covers each employee required by this section to use a
respirator.
(ii) For air-purifying respirators, the
employer must replace the air-purifying element at the expiration of its
service life or at the beginning of each
shift in which such elements are used,
whichever comes first.
(iii) If NIOSH approves an air-purifying element with an end-of-servicelife indicator for benzene, such an element may be used until the indicator
shows no further useful life.
(3) Respirator selection. (i) Employers
must:
(A) Select, and provide to employees,
the appropriate respirators specified in
paragraph (d)(3)(i)(A) of 29 CFR
1910.134.
(B) Provide employees with any organic vapor gas mask or any self-contained breathing apparatus with a full
facepiece to use for escape.
(C) Use an organic vapor cartridge or
canister with powered and non-powered
air-purifying respirators, and a chinstyle canister with full facepiece gas
masks.
(D) Ensure that canisters used with
non-powered air-purifying respirators
have a minimum service life of four
hours when tested at 150 ppm benzene
at a flow rate of 64 liters per minute
(LPM), a temperature of 25 °C, and a
relative humidity of 85%; for canisters
used with tight-fitting or loose-fitting
powered air-purifying respirators, the

flow rates for testing must be 115 LPM
and 170 LPM, respectively.
(ii) Any employee who cannot use a
negative-pressure respirator must be
allowed to use a respirator with less
breathing resistance, such as a powered
air-purifying respirator or supplied-air
respirator.
(h) Protective clothing and equipment.
Personal protective clothing and equipment shall be worn where appropriate
to prevent eye contact and limit dermal exposure to liquid benzene. Protective clothing and equipment shall be
provided by the employer at no cost to
the employee and the employer shall
assure its use where appropriate. Eye
and face protection shall meet the requirements of 29 CFR 1910.133.
(i) Medical surveillance—(1) General. (i)
The employer shall make available a
medical surveillance program for employees who are or may be exposed to
benzene at or above the action level 30
or more days per year; for employees
who are or may be exposed to benzene
at or above the PELs 10 or more days
per year; for employees who have been
exposed to more than 10 ppm of benzene for 30 or more days in a year prior
to the effective date of the standard
when employed by their current employer; and for employees involved in
the tire building operations called tire
building machine operators, who use
solvents containing greater than 0.1
percent benzene.
(ii) The employer shall assure that
all medical examinations and procedures are performed by or under the supervision of a licensed physician and
that all laboratory tests are conducted
by an accredited laboratory.
(iii) The employer shall assure that
persons other than licensed physicians
who administer the pulmonary function testing required by this section
shall complete a training course in
spirometry sponsored by an appropriate governmental, academic or professional institution.
(iv) The employer shall assure that
all examinations and procedures are
provided without cost to the employee
and at a reasonable time and place.
(2) Initial examination. (i) Within 60
days of the effective date of this standard, or before the time of initial assignment, the employer shall provide each

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Occupational Safety and Health Admin., Labor
employee covered by paragraph (i)(1)(i)
of this section with a medical examination including the following elements:
(A) A detailed occupational history
which includes:
(1) Past work exposure to benzene or
any other hematological toxins,
(2) A family history of blood
dyscrasias including hematological
neoplasms;
(3) A history of blood dyscrasias including genetic hemoglobin abnormalities, bleeding abnormalities, abnormal
function of formed blood elements;
(4) A history of renal or liver dysfunction;
(5) A history of medicinal drugs routinely taken;
(6) A history of previous exposure to
ionizing radiation and
(7) Exposure to marrow toxins outside of the current work situation.
(B) A complete physical examination.
(C) Laboratory tests. A complete blood
count including a leukocyte count with
differential,
a
quantitative
thrombocyte count, hematocrit, hemoglobin, erythrocyte count and erythrocyte indices (MCV, MCH, MCHC).
The results of these tests shall be reviewed by the examining physician.
(D) Additional tests as necessary in
the opinion of the examining physician, based on alterations to the components of the blood or other signs
which may be related to benzene exposure; and
(E) For all workers required to wear
respirators for at least 30 days a year,
the physical examination shall pay special attention to the cardiopulmonary
system and shall include a pulmonary
function test.
(ii) No initial medical examination is
required to satisfy the requirements of
paragraph (i)(2)(i) of this section if adequate records show that the employee
has been examined in accordance with
the procedures of paragraph (i)(2)(i) of
this section within the twelve months
prior to the effective date of this standard.
(3) Periodic examinations. (i) The employer shall provide each employee
covered under paragraph (i)(1)(i) of this
section with a medical examination annually following the previous examination. These periodic examinations shall
incude at least the following elements:

§ 1910.1028

(A) A brief history regarding any new
exposure to potential marrow toxins,
changes in medicinal drug use, and the
appearance of physical signs relating
to blood disorders:
(B) A complete blood count including
a leukocyte count with differential,
quantitative thrombocyte count, hemoglobin,
hematocrit,
erythrocyte
count and erythrocyte indices (MCV,
MCH, MCHC); and
(C) Appropriate additional tests as
necessary, in the opinion of the examining physician, in consequence of alterations in the components of the
blood or other signs which may be related to benzene exposure.
(ii) Where the employee develops
signs and symptoms commonly associated with toxic exposure to benzene,
the employer shall provide the employee with an additional medical examination which shall include those
elements considered appropriate by the
examining physician.
(iii) For persons required to use respirators for at least 30 days a year, a
pulmonary function test shall be performed every three (3) years. A specific
evaluation of the cardiopulmonary system shall be made at the time of the
pulmonary function test.
(4) Emergency examinations. (i) In addition to the surveillance required by
(i)(1)(i), if an employee is exposed to
benzene in an emergency situation, the
employer shall have the employee provide a urine sample at the end of the
employee’s shift and have a urinary
phenol test performed on the sample
within 72 hours. The urine specific
gravity shall be corrected to 1.024.
(ii) If the result of the urinary phenol
test is below 75 mg phenol/L of urine,
no further testing is required.
(iii) If the result of the urinary phenol test is equal to or greater than 75
mg phenol/L of urine, the employer
shall provide the employee with a complete blood count including an erythrocyte count, leukocyte count with differential and thrombocyte count at
monthly intervals for a duration of
three (3) months following the emergency exposure.
(iv) If any of the conditions specified
in paragraph (i)(5)(i) of this section exists, then the further requirements of
paragraph (i)(5) of this section shall be

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29 CFR Ch. XVII (7–1–09 Edition)

met and the employer shall, in addition, provide the employees with periodic examinations if directed by the
physician.
(5) Additional examinations and referrals. (i) Where the results of the complete blood count required for the initial and periodic examinations indicate
any of the following abnormal conditions exist, then the blood count shall
be repeated within 2 weeks.
(A) The hemoglobin level or the hematocrit falls below the normal limit
[outside the 95% confidence interval
(C.I.)] as determined by the laboratory
for the particular geographic area and/
or these indices show a persistent
downward trend from the individual’s
pre-exposure norms; provided these
findings cannot be explained by other
medical reasons.
(B) The thrombocyte (platelet) count
varies more than 20 percent below the
employee’s most recent values or falls
outside the normal limit (95% C.I.) as
determined by the laboratory.
(C) The leukocyte count is below
4,000 per mm3 or there is an abnormal
differential count.
(ii) If the abnormality persists, the
examining physician shall refer the
employee to a hematologist or an internist for further evaluation unless
the physician has good reason to believe such referral is unnecessary. (See
Appendix C for examples of conditions
where a referral may be unnecessary.)
(iii) The employer shall provide the
hematologist or internist with the information required to be provided to
the physician under paragraph (i)(6) of
this section and the medical record required to be maintained by paragraph
(k)(2)(ii) of this section.
(iv) The hematologist’s or internist’s
evaluation shall include a determination as to the need for additional tests,
and the employer shall assure that
these tests are provided.
(6) Information provided to the physician. The employer shall provide the
following information to the examining physician:
(i) A copy of this regulation and its
appendices;
(ii) A description of the affected employee’s duties as they relate to the
employee’s exposure;

(iii) The employee’s actual or representative exposure level:
(iv) A description of any personal
protective equipment used or to be
used; and
(v) Information from previous employment-related medical examinations of the affected employee which is
not otherwise available to the examining physician.
(7) Physician’s written opinions. (i) For
each examination under this section,
the employer shall obtain and provide
the employee with a copy of the examining physician’s written opinion within 15 days of the examination. The
written opinion shall be limited to the
following information:
(A) The occupationally pertinent results of the medical examination and
tests;
(B) The physician’s opinion concerning whether the employee has any
detected medical conditions which
would place the employee’s health at
greater than normal risk of material
impairment from exposure to benzene;
(C) The physician’s recommended
limitations upon the employee’s exposure to benzene or upon the employee’s
use of protective clothing or equipment
and respirators.
(D) A statement that the employee
has been informed by the physician of
the results of the medical examination
and any medical conditions resulting
from benzene exposure which require
further explanation or treatment.
(ii) The written opinion obtained by
the employer shall not reveal specific
records, findings and diagnoses that
have no bearing on the employee’s ability to work in a benzene-exposed workplace.
(8) Medical removal plan. (i) When a
physician makes a referral to a hematologist/internist as required under
paragraph (i)(5)(ii) of this section, the
employee shall be removed from areas
where exposures may exceed the action
level until such time as the physician
makes a determination under paragraph (i)(8)(ii) of this section.
(ii) Following the examination and
evaluation by the hematologist/internist, a decision to remove an employee
from areas where benzene exposure is
above the action level or to allow the

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employee to return to areas where benzene exposure is above the action level
shall be made by the physician in consultation with the hematologist/internist. This decision shall be communicated in writing to the employer and
employee. In the case of removal, the
physician shall state the required probable duration of removal from occupational exposure to benzene above the
action level and the requirements for
future medical examinations to review
the decision.
(iii) For any employee who is removed pursuant to paragraph (i)(8)(ii)
of this section, the employer shall provide a follow-up examination. The physician, in consultation with the hematologist/internist, shall make a decision within 6 months of the date the
employee was removed as to whether
the employee shall be returned to the
usual job or whether the employee
should be removed permanently.
(iv) Whenever an employee is temporarily removed from benzene exposure
pursuant to paragraph (i)(8)(i) or
(i)(8)(ii) of this section, the employer
shall transfer the employee to a comparable job for which the employee is
qualified (or can be trained for in a
short period) and where benzene exposures are as low as possible, but in no
event higher than the action level. The
employer shall maintain the employee’s current wage rate, seniority and
other benefits. If there is no such job
available, the employer shall provide
medical removal protection benefits
until such a job becomes available or
for 6 months, whichever comes first.
(v) Whenever an employee is removed
permanently from benzene exposure
based on a physician’s recommendation
pursuant to paragraph (i)(8)(iii) of this
section, the employee shall be given
the opportunity to transfer to another
position which is available or later becomes available for which the employee is qualified (or can be trained
for in a short period) and where benzene exposures are as low as possible
but in no event higher than the action
level. The employer shall assure that
such employee suffers no reduction in
current wage rate, seniority or other
benefits as a result of the transfer.
(9) Medical removal protection benefits.
(i) The employer shall provide to an

§ 1910.1028

employee 6 months of medical removal
protection benefits immediately following each occasion an employee is
removed from exposure to benzene because of hematological findings pursuant to paragraphs (i)(8) (i) and (ii) of
this section, unless the employee has
been transferred to a comparable job
where benzene exposures are below the
action level.
(ii) For the purposes of this section,
the requirement that an employer provide medical removal protection benefits means that the employer shall
maintain the current wage rate, seniority and other benefits of an employee
as though the employee had not been
removed.
(iii) The employer’s obligation to
provide medical removal protection
benefits to a removed employee shall
be reduced to the extent that the employee receives compensation for earnings lost during the period of removal
either from a publicly or employerfunded compensation program, or from
employment with another employer
made possible by virtue of the employee’s removal.
(j) Communication of benzene hazards
to employees—(1) Signs and labels. (i) The
employer shall post signs at entrances
to regulated areas. The signs shall bear
the following legend:
DANGER
BENZENE
CANCER HAZARD
FLAMMABLE—NO SMOKING
AUTHORIZED PERSONNEL ONLY
RESPIRATOR REQUIRED

(ii) The employer shall ensure that
lables or other appropriate forms of
warning are provided for containers of
benzene within the workplace. There is
no requirement to label pipes. The labels shall comply with the requirements of 29 CFR 1910.1200(f) and in addition shall include the following legend:
DANGER
CONTAINS BENZENE
CANCER HAZARD

(2) Material safety data sheets. (i) Employers shall obtain or develop, and
shall provide access to their employees, to a material safety data sheet
(MSDS) which addresses benzene and
complies with 29 CFR 1910.1200.

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§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

(ii) Employers who are manufacturers or importers shall:
(A) Comply with paragraph (a) of this
section, and
(B) Comply with the requirement in
OSHA’s Hazard Communication Standard, 29 CFR 1910.1200, that they deliver
to downstream employers an MSDS
which addresses benzene.
(3) Information and training. (i) The
employer shall provide employees with
information and training at the time of
their initial assignment to a work area
where benzene is present. If exposures
are above the action level, employees
shall be provided with information and
training at least annually thereafter.
(ii) The training program shall be in
accordance with the requirements of 29
CFR 1910.1200(h) (1) and (2), and shall
include specific information on benzene
for each category of information included in that section.
(iii) In addition to the information
required under 29 CFR 1910.1200, the
employer shall:
(A) Provide employees with an explanation of the contents of this section,
including Appendices A and B, and indicate to them where the standard is
available; and
(B) Describe the medical surveillance
program required under paragraph (i)
of this section, and explain the information contained in Appendix C.
(k) Recordkeeping—(1) Exposure measurements. (i) The employer shall establish and maintain an accurate record of
all measurements required by paragraph (e) of this section, in accordance
with 29 CFR 1910.20.
(ii) This record shall include:
(A) The dates, number, duration, and
results of each of the samples taken,
including a description of the procedure used to determine representative
employee exposures;
(B) A description of the sampling and
analytical methods used;
(C) A description of the type of respiratory protective devices worn, if
any; and
(D) The name, social security number, job classification and exposure levels of the employee monitored and all
other employees whose exposure the
measurement is intended to represent.

(iii) The employer shall maintain
this record for at least 30 years, in accordance with 29 CFR 1910.20.
(2) Medical surveillance. (i) The employer shall establish and maintain an
accurate record for each employee subject to medical surveillance required
by paragraph (i) of this section, in accordance with 29 CFR 1910.20.
(ii) This record shall include:
(A) The name and social security
number of the employee;
(B) The employer’s copy of the physician’s written opinion on the initial,
periodic and special examinations, including results of medical examinations and all tests, opinions and recommendations;
(C) Any employee medical complaints related to exposure to benzene;
(D) A copy of the information provided to the physician as required by
paragraphs (i)(6) (ii) through (v) of this
section; and
(E) A copy of the employee’s medical
and work history related to exposure
to benzene or any other hematologic
toxins.
(iii) The employer shall maintain
this record for at least the duration of
employment plus 30 years, in accordance with 29 CFR 1910.20.
(3) Availability. (i) The employer shall
assure that all records required to be
maintained by this section shall be
made available upon request to the Assistant Secretary and the Director for
examination and copying.
(ii) Employee exposure monitoring
records required by this paragraph
shall be provided upon request for examination and copying to employees,
employee representatives, and the Assistant Secretary in accordance with 29
CFR 1910.20 (a) through (e) and (g)
through (i).
(iii) Employee medical records required by this paragraph shall be provided upon request for examination and
copying, to the subject employee, to
anyone having the specific written consent of the subject employee, and to
the Assistant Secretary in accordance
with 29 CFR 1910.20.
(4) Transfer of records. (i) The employer shall comply with the requirements involving transfer of records set
forth in 29 CFR 1019.20(h).

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Occupational Safety and Health Admin., Labor
(ii) If the employer ceases to do business and there is no successor employer
to receive and retain the records for
the prescribed period, the employer
shall notify the Director, at least three
(3) months prior to disposal, and transmit them to the Director if required by
the Director within that period.
(l) Observation of monitoring—(1) Employee observation. The employer shall
provide affected employees, or their
designated representatives, an opportunity to observe the measuring or
monitoring of employee exposure to
benzene conducted pursuant to paragraph (e) of this section.
(2) Observation procedures. When observation of the measuring or monitoring of employee exposure to benzene
requires entry into areas where the use
of protective clothing and equipment
or respirators is required, the employer
shall provide the observer with personal protective clothing and equipment or respirators required to be worn
by employees working in the area, assure the use of such clothing and equipment or respirators, and require the
observer to comply with all other applicable safety and health procedures.
(m) [Reserved]
(n) Appendices. The information contained in Appendices A, B, C, and D is
not intended, by itself, to create any
additional obligations not otherwise
imposed or to detract from any existing obligations.
APPENDIX A TO § 1910.1028—SUBSTANCE
SAFETY DATA SHEET, BENZENE

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I. SUBSTANCE IDENTIFICATION
A. Substance: Benzene.
B. Permissible Exposure: Except as to the
use of gasoline, motor fuels and other fuels
subsequent to discharge from bulk terminals
and
other
exemptions
specified
in
§ 1910.1028(a)(2):
1. Airborne: The maximum time-weighted
average (TWA) exposure limit is 1 part of
benzene vapor per million parts of air (1
ppm) for an 8-hour workday and the maximum short-term exposure limit (STEL) is 5
ppm for any 15-minute period.
2. Dermal: Eye contact shall be prevented
and skin contact with liquid benzene shall be
limited.
C. Appearance and odor: Benzene is a clear,
colorless liquid with a pleasant, sweet odor.
The odor of benzene does not provide adequate warning of its hazard.

§ 1910.1028
II. HEALTH HAZARD DATA

A. Ways in which benzene affects your
health. Benzene can affect your health if you
inhale it, or if it comes in contact with your
skin or eyes. Benzene is also harmful if you
happen to swallow it.
B. Effects of overexposure. 1. Short-term
(acute) overexposure: If you are overexposed
to high concentrations of benzene, well
above the levels where its odor is first recognizable, you may feel breathless, irritable,
euphoric, or giddy; you may experience irritation in eyes, nose, and respiratory tract.
You may develop a headache, feel dizzy, nauseated, or intoxicated. Severe exposures may
lead to convulsions and loss of consciousness.
2. Long-term (chronic) exposure. Repeated
or prolonged exposure to benzene, even at
relatively low concentrations, may result in
various blood disorders, ranging from anemia
to leukemia, an irreversible, fatal disease.
Many blood disorders associated with benzene exposure may occur without symptoms.
III. PROTECTIVE CLOTHING AND EQUIPMENT
A. Respirators. Respirators are required for
those operations in which engineering controls or work practice controls are not feasible to reduce exposure to the permissible
level. However, where employers can document that benzene is present in the workplace less than 30 days a year, respirators
may be used in lieu of engineering controls.
If respirators are worn, they must have joint
Mine Safety and Health Administration and
the National Institute for Occupational Safety and Health (NIOSH) seal of approval, and
cartridge or canisters must be replaced before the end of their service life, or the end
of the shift, whichever occurs first. If you experience difficulty breathing while wearing a
respirator, you may request a positive pressure respirator from your employer. You
must be thoroughly trained to use the assigned respirator, and the training will be
provided by your employer.
B. Protective Clothing. You must wear appropriate protective clothing (such as boots,
gloves, sleeves, aprons, etc.) over any parts
of your body that could be exposed to liquid
benzene.
C. Eye and Face Protection. You must wear
splash-proof safety goggles if it is possible
that benzene may get into your eyes. In addition, you must wear a face shield if your
face could be splashed with benzene liquid.
IV. EMERGENCY AND FIRST AID PROCEDURES
A. Eye and face exposure. If benzene is
splashed in your eyes, wash it out immediately with large amounts of water. If irritation persists or vision appears to be affected see a doctor as soon as possible.

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§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

B. Skin exposure. If benzene is spilled on
your clothing or skin, remove the contaminated clothing and wash the exposed skin
with large amounts of water and soap immediately. Wash contaminated clothing before
you wear it again.
C. Breathing. If you or any other person
breathes in large amounts of benzene, get
the exposed person to fresh air at once.
Apply artificial respiration if breathing has
stopped. Call for medical assistance or a doctor as soon as possible. Never enter any vessel or confined space where the benzene concentration might be high without proper
safety equipment and at least one other person present who will stay outside. A life line
should be used.
D. Swallowing. If benzene has been swallowed and the patient is conscious, do not induce vomiting. Call for medical assistance or
a doctor immediately.
V. MEDICAL REQUIREMENTS
If you are exposed to benzene at a concentration at or above 0.5 ppm as an 8-hour
time-weighted average, or have been exposed
at or above 10 ppm in the past while employed by your current employer, your employer is required to provide a medical examination and history and laboratory tests
within 60 days of the effective date of this
standard and annually thereafter. These
tests shall be provided without cost to you.
In addition, if you are accidentally exposed
to benzene (either by ingestion, inhalation,
or skin/eye contact) under emergency conditions known or suspected to constitute toxic
exposure to benzene, your employer is required to make special laboratory tests
available to you.
VI. OBSERVATION OF MONITORING
Your employer is required to perform
measurements that are representative of
your exposure to benzene and you or your
designated representative are entitled to observe the monitoring procedure. You are entitled to observe the steps taken in the
measurement procedure, and to record the
results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and
equipment are required to be worn, you or
your representative must also be provided
with, and must wear the protective clothing
and equipment.

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VII. ACCESS TO RECORDS
You or your representative are entitled to
see the records of measurements of your exposure to benzene upon written request to
your employer. Your medical examination
records can be furnished to yourself, your
physician or designated representative upon
request by you to your employer.

VIII. PRECAUTIONS FOR SAFE USE, HANDLING
AND STORAGE
Benzene liquid is highly flammable. It
should be stored in tightly closed containers
in a cool, well ventilated area. Benzene vapor
may form explosive mixtures in air. All
sources of ignition must be controlled. Use
nonsparking tools when opening or closing
benzene containers. Fire extinguishers,
where provided, must be readily available.
Know where they are located and how to operate them. Smoking is prohibited in areas
where benzene is used or stored. Ask your supervisor where benzene is used in your area
and for additional plant safety rules.
APPENDIX B TO § 1910.1028—SUBSTANCE
TECHNICAL GUIDELINES, BENZENE
I. PHYSICAL AND CHEMICAL DATA
A. Substance identification.
1. Synonyms: Benzol, benzole, coal naphtha,
cyclohexatriene, phene, phenyl hydride,
pyrobenzol. (Benzin, petroleum benzin and
Benzine do not contain benzene).
2. Formula: C6 H6 (CAS Registry Number:
71–43–2)
B. Physical data.
1. Boiling Point (760 mm Hg); 80.1 °C (176
°F)
2. Specific Gravity (water=1): 0.879
3. Vapor Density (air=1): 2.7
4. Melting Point: 5.5 °C (42 °F)
5. Vapor Pressure at 20 °C (68 °F): 75 mm Hg
6. Solubility in Water: .06%
7. Evaporation Rate (ether=1): 2.8
8. Appearance and Odor: Clear, colorless
liquid with a distinctive sweet odor.
II. FIRE, EXPLOSION, AND REACTIVITY HAZARD
DATA
A. Fire.
1. Flash Point (closed cup): ¥11 °C (12 °F)
2. Autoignition Temperature: 580 °C (1076
°F)
3. Flammable limits in Air. % by Volume:
Lower: 1.3%, Upper: 7.5%
4. Extinguishing Media: Carbon dioxide,
dry chemical, or foam.
5. Special Fire-Fighting procedures: Do not
use solid stream of water, since stream will
scatter and spread fire. Fine water spray can
be used to keep fire-exposed containers cool.
6. Unusual fire and explosion hazards: Benzene is a flammable liquid. Its vapors can
form explosive mixtures. All ignition sources
must be controlled when benzene is used,
handled, or stored. Where liquid or vapor
may be released, such areas shall be considered as hazardous locations. Benzene vapors
are heavier than air; thus the vapors may
travel along the ground and be ignited by
open flames or sparks at locations remote
from the site at which benzene is handled.
7. Benzene is classified as a 1 B flammable
liquid for the purpose of conforming to the

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Occupational Safety and Health Admin., Labor
requirements of 29 CFR 1910.106. A concentration exceeding 3,250 ppm is considered
a potential fire explosion hazard. Locations
where benzene may be present in quantities
sufficient to produce explosive or ignitable
mixtures are considered Class I Group D for
the purposes of conforming to the requirements of 29 CFR 1910.309.
B. Reactivity.
1. Conditions contributing to instability:
Heat.
2. Incompatibility: Heat and oxidizing materials.
3. Hazardous decomposition products:
Toxic gases and vapors (such as carbon monoxide).
III. SPILL AND LEAK PROCEDURES
A. Steps to be taken if the material is released or spilled. As much benzene as possible should be absorbed with suitable materials, such as dry sand or earth. That remaining must be flushed with large amounts
of water. Do not flush benzene into a confined space, such as a sewer, because of explosion danger. Remove all ignition sources.
Ventilate enclosed places.
B. Waste disposal method. Disposal methods must conform to other jurisdictional regulations. If allowed, benzene may be disposed
of: (a) By absorbing it in dry sand or earth
and disposing in a sanitary landfill; (b) if
small quantities, by removing it to a safe location from buildings or other combustible
sources, pouring it in dry sand or earth and
cautiously igniting it; and (c) if large quantities, by atomizing it in a suitable combustion chamber.
IV. MISCELLANEOUS PRECAUTIONS
A. High exposure to benzene can occur
when transferring the liquid from one container to another. Such operations should be
well ventilated and good work practices
must be established to avoid spills.
B. Use non-sparking tools to open benzene
containers which are effectively grounded
and bonded prior to opening and pouring.
C. Employers must advise employees of all
plant areas and operations where exposure to
benzene could occur. Common operations in
which high exposures to benzene may be encountered are: the primary production and
utilization of benzene, and transfer of benzene.
APPENDIX C TO § 1910.1028—MEDICAL
SURVEILLANCE GUIDELINES FOR BENZENE
I. ROUTE OF ENTRY
Inhalation; skin absorption.

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II. TOXICOLOGY
Benzene is primarily an inhalation hazard.
Systemic absorption may cause depression of
the hematopoietic system, pancytopenia,

§ 1910.1028

aplastic anemia, and leukemia. Inhalation of
high concentrations can affect central nervous system function. Aspiration of small
amounts of liquid benzene immediately
causes pulmonary edema and hemorrhage of
pulmonary tissue. There is some absorption
through the skin. Absorption may be more
rapid in the case of abraded skin, and benzene may be more readily absorbed if it is
present in a mixture or as a contaminant in
solvents which are readily absorbed. The
defatting action of benzene may produce primary irritation due to repeated or prolonged
contact with the skin. High concentration
are irritating to the eyes and the mucuous
membranes of the nose, and respiratory
tract.
III. SIGNS AND SYMPTOMS
Direct skin contact with benzene may
cause erythema. Repeated or prolonged contact may result in drying, scaling dermatitis, or development of secondary skin infections. In addition, there is benzene absorption through the skin. Local effects of
benzene vapor or liquid on the eye are slight.
Only at very high concentrations is there
any smarting sensation in the eye. Inhalation of high concentrations of benzene may
have an initial stimulatory effect on the central nervous system characterized by exhilaration, nervous excitation, and/or giddiness,
followed by a period of depression, drowsiness, or fatigue. A sensation of tightness in
the chest accompanied by breathlessness
may occur and ultimately the victim may
lose consciousness. Tremors, convulsions and
death may follow from respiratory paralysis
or circulatory collapse in a few minutes to
several hours following severe exposures.
The detrimental effect on the blood-forming system of prolonged exposure to small
quantities of benzene vapor is of extreme importance. The hematopoietic system is the
chief target for benzene’s toxic effects which
are manifested by alterations in the levels of
formed elements in the peripheral blood.
These effects have occurred at concentrations of benzene which may not cause irritation of mucous membranes, or any unpleasant sensory effects. Early signs and symptoms of benzene morbidity are varied, often
not readily noticed and non-specific. Subjective complaints of headache, dizziness, and
loss of appetite may precede or follow clinical signs. Rapid pulse and low blood pressure, in addition to a physical appearance of
anemia, may accompany a subjective complaint of shortness of breath and excessive
tiredness. Bleeding from the nose, gums, or
mucous membranes, and the development of
purpuric spots (small bruises) may occur as
the condition progresses. Clinical evidence of
leukopenia, anemia, and thrombocytopenia,
singly or in combination, has been frequently reported among the first signs.

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§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

Bone marrow may appear normal, aplastic,
or hyperplastic, and may not, in all situations, correlate with peripheral blood forming tissues. Because of variations in the susceptibility to benzene morbidity, there is no
‘‘typical’’ blood picture. The onset of effects
of prolonged benzene exposure may be delayed for many months or years after the actual exposure has ceased and identification
or correlation with benzene exposure must
be sought out in the occupational history.
IV. TREATMENT OF ACUTE TOXIC EFFECTS
Remove from exposure immediately. Make
sure you are adequately protected and do not
risk being overcome by fumes. Give oxygen
or artificial resuscitation if indicated. Flush
eyes, wash skin if contaminated and remove
all contaminated clothing. Symptoms of intoxication may persist following severe exposures. Recovery from mild exposures is
usually rapid and complete.
V. SURVEILLANCE AND PREVENTIVE
CONSIDERATIONS

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A. General
The principal effects of benzene exposure
which form the basis for this regulation are
pathological changes in the hematopoietic
system, reflected by changes in the peripheral blood and manifesting clinically as
pancytopenia, aplastic anemia, and leukemia. Consequently, the medical surveillance program is designed to observe, on a
regular basis, blood indices for early signs of
these effects, and although early signs of leukemia are not usually available, emerging
diagnostic technology and innovative regimes make consistent surveillance for leukemia, as well as other hematopoietic effects, essential.
Initial examinations are to be provided
within 60 days of the effective date of this
standard, or at the time of initial assignment, and periodic examinations annually
thereafter. There are special provisions for
medical tests in the event of hematologic abnormalities or for emergency situations.
The blood values which require referral to
a hematologist or internist are noted in the
standard in paragraph (i)(5). The standard
specifies that blood abnormalities that persist must be referred ‘‘unless the physician
has good reason to believe such referral is
unnecessary’’ (paragraph (i)(5)). Examples of
conditions that could make a referral unnecessary despite abnormal blood limits are
iron or folate deficiency, menorrhagia, or
blood loss due to some unrelated medical abnormality.
Symptoms and signs of benzene toxicity
can be non-specific. Only a detailed history
and appropriate investigative procedures
will enable a physician to rule out or confirm conditions that place the employee at
increased risk. To assist the examining phy-

sician with regard to which laboratory tests
are necessary and when to refer an employee
to the specialist, OSHA has established the
following guidelines.
B. Hematology Guidelines
A minimum battery of tests is to be performed by strictly standardized methods.
1. Red cell, white cell, platelet counts,
white blood cell differential, hematacrit and
red cell indices must be performed by an accredited laboratory. The normal ranges for
the red cell and white cell counts are influenced by altitude, race, and sex, and therefore should be determined by the accredited
laboratory in the specific area where the
tests are performed.
Either a decline from an absolute normal
or an individual’s base line to a subnormal
value or a rise to a supra-normal value, are
indicative of potential toxicity, particularly
if all blood parameters decline. The normal
total white blood count is approximately
7,200/mm3 plus or minus 3,000. For cigarette
smokers the white count may be higher and
the upper range may be 2,000 cells higher
than normal for the laboratory. In addition,
infection, allergies and some drugs may raise
the white cell count. The normal platelet
count is approximately 250,000 with a range
of 140,000 to 400,000. Counts outside this range
should be regarded as possible evidence of
benzene toxicity.
Certain abnormalities found through routine screening are of greater significance in
the benzene-exposed worker and require
prompt consultation with a specialist, namely:
a. Thrombocytopenia.
b. A trend of decreasing white cell, red cell,
or platelet indices in an individual over time
is more worrisome than an isolated abnormal finding at one test time. The importance
of trend highlights the need to compare an
individual’s test results to baseline and/or
previous periodic tests.
c. A constellation or pattern of abnormalities in the different blood indices is of more
significance than a single abnormality. A
low white count not associated with any abnormalities in other cell indices may be a
normal statistical variation, whereas if the
low white count is accompanied by decreases
in the platelet and/or red cell indices, such a
pattern is more likely to be associated with
benzene toxicity and merits thorough investigation.
Anemia, leukopenia, macrocytosis or an
abnormal differential white blood cell count
should alert the physician to further investigate and/or refer the patient if repeat tests
confirm the abnormalities. If routine screening detects an abnormality, follow-up tests
which may be helpful in establishing the etiology of the abnormality are the peripheral
blood smear and the reticulocyte count.

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Occupational Safety and Health Admin., Labor
The extreme range of normal for
reticulocytes is 0.4 to 2.5 percent of the red
cells, the usual range being 0.5 to 1.2 percent
of the red cells, but the typical value is in
the range of 0.8 to 1.0 percent. A decline in
reticulocytes to levels of less than 0.4 percent is to be regarded as possible evidence
(unless another specific cause is found) of
benzene toxicity requiring accelerated surveillance. An increase in reticulocyte levels
to about 2.5 percent may also be consistent
with (but is not as characteristic of) benzene
toxicity.
2. An important diagnostic test is a careful
examination of the peripheral blood smear.
As with reticulocyte count the smear should
be with fresh uncoagulated blood obtained
from a needle tip following venipuncture or
from a drop of earlobe blood (capillary
blood). If necessary, the smear may, under
certain limited conditions, be made from a
blood sample anticoagulated with EDTA (but
never with oxalate or heparin). When the
smear is to be prepared from a specimen of
venous blood which has been collected by a
commercial Vacutainer ® type tube containing neutral EDTA, the smear should be
made as soon as possible after the
venesection. A delay of up to 12 hours is permissible between the drawing of the blood
specimen into EDTA and the preparation of
the smear if the blood is stored at refrigerator (not freezing) temperature.
3. The minimum mandatory observations
to be made from the smear are:
a. The differential white blood cell count.
b. Description of abnormalities in the appearance of red cells.
c. Description of any abnormalities in the
platelets.
d. A careful search must be made throughout of every blood smear for immature white
cells such as band forms (in more than normal proportion, i.e., over 10 percent of the
total differential count), any number of
metamyelocytes, myelocytes or myeloblasts.
Any nucleate or multinucleated red blood
cells should be reported. Large ‘‘giant’’
platelets or fragments of megakaryocytes
must be recognized.
An increase in the proportion of band
forms among the neutrophilic granulocytes
is an abnormality deserving special mention,
for it may represent a change which should
be considered as an early warning of benzene
toxicity in the absence of other causative
factors (most commonly infection). Likewise, the appearance of metamyelocytes, in
the absence of another probable cause, is to
be considered a possible indication of benzene-induced toxicity.
An upward trend in the number of
basophils, which normally do not exceed
about 2.0 percent of the total white cells, is
to be regarded as possible evidence of benzene toxicity. A rise in the eosinophil count
is less specific but also may be suspicious of

§ 1910.1028

toxicity if the rises above 6.0 percent of the
total white count.
The normal range of monocytes is from 2.0
to 8.0 percent of the total white count with
an average of about 5.0 percent. About 20 percent of individuals reported to have mild but
persisting abnormalities caused by exposure
to benzene show a persistent monocytosis.
The findings of a monocyte count which persists at more than 10 to 12 percent of the normal white cell count (when the total count is
normal) or persistence of an absolute monocyte count in excess of 800/mm3 should be regarded as a possible sign of benzene-induced
toxicity.
A less frequent but more serious indication
of benzene toxicity is the finding in the peripheral blood of the so-called ‘‘pseudo’’ (or
acquired) Pelger-Huet anomaly. In this
anomaly many, or sometimes the majority,
of the neutrophilic granulocytes possess two
round nuclear segements—less often one or
three round segments—rather than three
normally elongated segments. When this
anomaly is not hereditary, it is often but not
invariably predictive of subsequent leukemia. However, only about two percent of
patients who ultimately develop acute
myelogenous leukemia show the acquired
Pelger-Huet anomaly. Other tests that can
be administered to investigate blood abnormalities are discussed below; however, such
procedures should be undertaken by the hematologist.
An uncommon sign, which cannot be detected from the smear, but can be elicited by
a ‘‘sucrose water test’’ of peripheral blood, is
transient
paroxysmal
nocturnal
hemoglobinuria (PNH), which may first occur insidiously during a period of established
aplastic anemia, and may be followed within
one to a few years by the appearance of rapidly fatal acute myelogenous leukemia. Clinical detection of PNH, which occurs in only
one or two percent of those destined to have
acute myelogenous leukemia, may be difficult; if the ‘‘sucrose water test’’ is positive,
the somewhat more definitive Ham test, also
known as the acid-serum hemolysis test,
may provide confirmation.
e. Individuals documented to have developed acute myelogenous leukemia years
after initial exposure to benzene may have
progressed through a preliminary phase of
hematologic abnormality. In some instances
pancytopenia (i.e., a lowering in the counts
of all circulating blood cells of bone marrow
origin, but not to the extent implied by the
term ‘‘aplastic anemia’’) preceded leukemia
for many years. Depression of a single blood
cell type or platelets may represent a harbinger of aplasia or leukemia. The finding of
two or more cytopenias, or pancytopenia in
a benzene-exposed individual, must be regarded as highly suspicious of more advanced
although
still
reversible,
toxicity.
‘‘Pancytopenia’’ coupled with the appearance

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§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

of immature cells (myelocytes, myeloblasts,
erythroblasts, etc.), with abnormal cells
(pseudo Pelger-Huet anomaly, atypical nuclear heterochromatin, etc.), or unexplained
elevations of white blood cells must be regarded as evidence of benzene overexposure
unless proved otherwise. Many severely
aplastic patients manifested the ominous
finding of 5–10 percent myeloblasts in the
marrow,
occasional
myeloblasts
and
myelocytes in the blood and 20–30% monocytes. It is evident that isolated cytopenias,
pancytopenias, and even aplastic anemias induced by benzene may be reversible and complete recovery has been reported on cessation of exposure. However, since any of
these abnormalities is serious, the employee
must immediately be removed from any possible exposure to benzene vapor. Certain
tests may substantiate the employee’s prospects for progression or regression. One such
test would be an examination of the bone
marrow, but the decision to perform a bone
marrow aspiration or needle biopsy is made
by the hematologist.
The findings of basophilic stippling in circulating red blood cells (usually found in 1 to
5% of red cells following marrow injury), and
detection in the bone marrow of what are
termed ‘‘ringed sideroblasts’’ must be taken
seriously, as they have been noted in recent
years to be premonitory signs of subsequent
leukemia.
Recently peroxidase-staining of circulating
or marrow neutrophil granulocytes, employing benzidine dihydrochloride, have revealed
the disappearance of, or diminution in, peroxidase in a sizable proportion of the
granulocytes, and this has been reported as
an early sign of leukemia. However, relatively few patients have been studied to
date. Granulocyte granules are normally
strongly peroxidase positive. A steady decline in leukocyte alkaline phosphatase has
also been reported as suggestive of early
acute leukemia. Exposure to benzene may
cause an early rise in serum iron, often but
not always associated with a fall in the
reticulocyte count. Thus, serial measurements of serum iron levels may provide a
means of determining whether or not there
is a trend representing sustained suppression
of erythropoiesis.
Measurement of serum iron, determination
of peroxidase and of alkaline phosphatase activity in peripheral granulocytes can be performed in most pathology laboratories. Peroxidase and alkaline phosphatase staining
are usually undertaken when the index of
suspecion for leukemia is high.

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APPENDIX D TO § 1910.1028—SAMPLING AND ANALYTICAL METHODS FOR BENZENE MONITORING AND MEASUREMENT PROCEDURES
Measurements taken for the purpose of determining employee exposure to benzene are
best taken so that the representative aver-

age 8-hour exposure may be determined from
a single 8-hour sample or two (2) 4-hour samples. Short-time interval samples (or grab
samples) may also be used to determine average exposure level if a minimum of five
measurements are taken in a random manner over the 8-hour work shift. Random sampling means that any portion of the work
shift has the same change of being sampled
as any other. The arithmetic average of all
such random samples taken on one work
shift is an estimate of an employee’s average
level of exposure for that work shift. Air
samples should be taken in the employee’s
breathing zone (air that would most nearly
represent that inhaled by the employee).
Sampling and analysis must be performed
with procedures meeting the requirements of
the standard.
There are a number of methods available
for monitoring employee exposures to benzene. The sampling and analysis may be performed by collection of the benzene vaptor or
charcoal absorption tubes, with subsequent
chemical analysis by gas chromatography.
Sampling and analysis may also be performed by portable direct reading instruments, real-time continuous monitoring systems, passive dosimeters or other suitable
methods. The employer has the obligation of
selecting a monitoring method which meets
the accuracy and precision requirements of
the standard under his unique field conditions. The standard requires that the method
of monitoring must have an accuracy, to a 95
percent confidence level, of not less than
plus or minus 25 percent for concentrations
of benzene greater than or equal to 0.5 ppm.
The OSHA Laboratory modified NIOSH
Method S311 and evaluated it at a benzene
air concentration of 1 ppm. A procedure for
determining the benzene concentration in
bulk material samples was also evalauted.
This work, reported in OSHA Laboratory
Method No. 12, includes the following two
analytical procedures:
I. OSHA METHOD 12 FOR AIR SAMPLES
Analyte: Benzene
Matrix: Air
Procedure:
Adsorption
on
charcoal,
desorption with carbon disulfide, analysis
by GC.
Detection limit: 0.04 ppm
Recommended air volume and sampling rate:
10L to 0.2 L/min.
1. Principle of the Method.
1.1 A known volume of air is drawn
through a charcoal tube to trap the organic
vapors present.
1.2. The charcoal in the tube is transferred
to a small, stoppered vial, and the anlyte is
desorbed with carbon disulfide.
1.3. An aliquot of the desorbed sample is injected into a gas chromatograph.

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Occupational Safety and Health Admin., Labor
1.4 The area of the resulting peak is determined and compared with areas obtained
from standards.
2. Advantages and disadvantages of the
method.
2.1 The sampling device is small, portable,
and involved no liquids. Interferences are
minimal, and most of those which do occur
can
be
eliminated
by
altering
chromatographic conditions. The samples
are analyzed by means of a quick, instrumental method.
2.2 The amount of sample which can be
taken is limited by the number of milligrams that the tube will hold before overloading. When the sample value obtained for
the backup section of the charcoal tube exceeds 25 percent of that found on the front
section, the possibility of sample loss exists.
3. Apparatus.
3.1 A calibrated personal sampling pump
whose flow can be determined within ±5 percent at the recommended flow rate.
3.2. Charcoal tubes: Glass with both ends
flame sealed, 7 cm long with a 6-mm O.D. and
a 4-mm I.D., containing 2 sections of 20/40
mesh activated charcoal separated by a 2mm portion of urethane foam. The activated
charcoal is prepared from coconut shells and
is fired at 600 °C prior to packing. The adsorbing section contains 100 mg of charcoal,
the back-up section 50 mg. A 3-mm portion of
urethane foam is placed between the outlet
end of the tube and the back-up section. A
plug of silanized glass wool is placed in front
of the adsorbing section. The pressure drop
across the tube must be less than one inch of
mercury at a flow rate of 1 liter per minute.
3.3. Gas chromatograph equipped with a
flame ionization detector.
3.4. Column (10-ft × 1⁄8-in stainless steel)
packed with 80/100 Supelcoport coated with
20 percent SP 2100, 0.1 percent CW 1500.
3.5. An electronic integrator or some other
suitable method for measuring peak area.
3.6. Two-milliliter sample vials with Teflon-lined caps.
3.7. Microliter syringes: 10-microliter (10μL syringe, and other convenient sizes for
making standards, 1-μL syringe for sample
injections.
3.8. Pipets: 1.0 mL delivery pipets
3.9. Volumetric flasks: convenient sizes for
making standard solutions.
4. Reagents.
4.1. Chromatographic quality carbon disulfide (CS2). Most commercially available carbon disulfide contains a trace of benzene
which must be removed. It can be removed
with the following procedure:
Heat under reflux for 2 to 3 hours, 500 mL
of carbon disulfide, 10 mL concentrated sulfuric acid, and 5 drops of concentrated nitric
acid.
The
benzene
is
converted
to
nitrobenzene. The carbon disulfide layer is
removed, dried with anhydrous sodium sulfate, and distilled. The recovered carbon di-

§ 1910.1028

sulfide should be benzene free. (It has recently been determined that benzene can
also be removed by passing the carbon disulfide through 13x molecular sieve).
4.2. Benzene, reagent grade.
4.3. p-Cymene, reagent grade, (internal
standard).
4.4. Desorbing reagent. The desorbing reagent is prepared by adding 0.05 mL of p-cymene per milliliter of carbon disulfide. (The
internal standard offers a convenient means
correcting analytical response for slight inconsistencies in the size of sample injections. If the external standard technique is
preferred, the internal standard can be eliminated).
4.5. Purified GC grade helium, hydrogen
and air.
5. Procedure.
5.1. Cleaning of equipment. All glassware
used for the laboratory analysis should be
properly cleaned and free of organics which
could interfere in the analysis.
5.2. Calibration of personal pumps. Each
pump must be calibrated with a representative charcoal tube in the line.
5.3. Collection and shipping of samples.
5.3.1. Immediately before sampling, break
the ends of the tube to provide an opening at
least one-half the internal diameter of the
tube (2 mm).
5.3.2. The smaller section of the charcoal is
used as the backup and should be placed
nearest the sampling pump.
5.3.3. The charcoal tube should be placed in
a vertical position during sampling to minimize channeling through the charcoal.
5.3.4 Air being sampled should not be
passed through any hose or tubing before entering the charcoal tube.
5.3.5. A sample size of 10 liters is recommended. Sample at a flow rate of approximately 0.2 liters per minute. The flow rate
should be known with an accuracy of at least
±5 percent.
5.3.6. The charcoal tubes should be capped
with the supplied plastic caps immediately
after sampling.
5.3.7. Submit at least one blank tube (a
charcoal tube subjected to the same handling
procedures, without having any air drawn
through it) with each set of samples.
5.3.8. Take necessary shipping and packing
precautions to minimize breakage of samples.
5.4. Analysis of samples.
5.4.1. Preparation of samples. In preparation for analysis, each charcoal tube is
scored with a file in front of the first section
of charcoal and broken open. The glass wool
is removed and discarded. The charcoal in
the first (larger) section is transferred to a 2ml vial. The separating section of foam is removed and discarded; the second section is
transferred to another capped vial. These
two sections are analyzed separately.

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§ 1910.1028

29 CFR Ch. XVII (7–1–09 Edition)

5.4.2. Desorption of samples. Prior to analysis, 1.0 mL of desorbing solution is pipetted
into each sample container. The desorbing
solution consists of 0.05 μL internal standard
per mL of carbon disulfide. The sample vials
are capped as soon as the solvent is added.
Desorption should be done for 30 minutes
with occasional shaking.
5.4.3. GC conditions. Typical operating conditions for the gas chromatograph are:
1.30 mL/min (60 psig) helium carrier gas
flow.
2.30 mL/min (40 psig) hydrogen gas flow to
detector.
3.240 mL/min (40 psig) air flow to detector.
4.150 °C injector temperature.
5.250 °C detector temperature.
6.100 °C column temperature.
5.4.4. Injection size. 1 μL.
5.4.5. Measurement of area. The peak areas
are measured by an electronic integrator or
some other suitable form of area measurement.
5.4.6. An internal standard procedure is
used. The integrator is calibrated to report
results in ppm for a 10 liter air sample after
correction for desorption efficiency.
5.5. Determination of desorption efficiency.
5.5.1. Importance of determination. The
desorption efficiency of a particular compound can vary from one laboratory to another and from one lot of chemical to another. Thus, it is necessary to determine, at
least once, the percentage of the specific
compound that is removed in the desorption
process, provided the same batch of charcoal
is used.
5.5.2. Procedure for determining desorption
efficiency. The reference portion of the charcoal tube is removed. To the remaining portion, amounts representing 0.5X, 1X, and 2X
and (X represents target concentration)
based on a 10 L air sample are injected into
several tubes at each level. Dilutions of benzene with carbon disulfide are made to allow
injection of measurable quantities. These
tubes are then allowed to equilibrate at least
overnight. Following equilibration they are
analyzed following the same procedure as the
samples. Desorption efficiency is determined
by dividing the amount of benzene found by
amount spiked on the tube.
6. Calibration and standards. A series of
standards varying in concentration over the
range of interest is prepared and analyzed
under the same GC conditions that will be
used on the samples. A calibration curve is
prepared by plotting concentration (μg/mL)
versus peak area.
7. Calculations. Benzene air concentration
can be calculated from the following equation:
mg/m3=(A)(B)/(C)(D)
Where:
A=μg/mL benzene, obtained from the calibration curve

B=desorption volume (1 mL)
C=Liters of air sampled
D=desorption efficiency
The concentration in mg/m3 can be converted to ppm (at 25° and 760 mm) with following equation:
ppm=(mg/m3)(24.46)/(78.11)
Where:
24.46=molar volume of an ideal gas
25 °C and 760 mm
78.11=molecular weight of benzene
8. Backup Data.
8.1 Detection limit—Air Samples.
The detection limit for the analytical procedure is 1.28 ng with a coefficient of variation of 0.023 at this level. This would be
equivalent to an air concentration of 0.04
ppm for a 10 L air sample. This amount provided a chromatographic peak that could be
identifiable in the presence of possible interferences. The detection limit data were obtained by making 1 μL injections of a 1.283
μg/mL standard.
Area
Count

Injection
1
2
3
4
5
6

..........................................................
..........................................................
..........................................................
..........................................................
..........................................................
..........................................................

655.4
617.5
662.0
641.1
636.4
629.2

8.2. Pooled coefficient of variation—Air
Samples. The pooled coefficient of variation
for the analytical procedure was determined
by 1 μL replicate injections of analytical
standards. The standards were 16.04, 32.08,
and 64.16 μg/mL, which are equivalent to 0.5,
1.0, and 2.0 ppm for a 10 L air sample respectively.
Area Counts
Injection
1 .............................
2 .............................
3 .............................
4 .............................
5 .............................
6 .............................
X¯=
SD=
CV=
¯ V¯=0.008 ...............
C

0.5 ppm

1.0 ppm

2.0 ppm

3996.5
4059.4
4052.0
4027.2
4046.8
4137.9
4053.3
47.2
0.0116
..................

8130.2
8235.6
8307.9
8263.2
8291.1
8288.8
8254.0
62.5
0.0076
..................

16481
16493
16535
16609
16552
16618
16548.3
57.1
0.0034
....................

8.3. Storage data—Air Samples
Samples were generated at 1.03 ppm benzene at 80% relative humidity, 22 °C, and 643
mm. All samples were taken for 50 minutes
at 0.2 L/min. Six samples were analyzed immediately and the rest of the samples were
divided into two groups by fifteen samples
each. One group was stored at refrigerated
temperature of ¥25 °C, and the other group
was stored at ambient temperature (approximately 23 °C). These samples were analyzed

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Occupational Safety and Health Admin., Labor
over a period of fifteen days. The results are
tabulated below.

PERCENT RECOVERY
Day analyzed

Refrigerated

0 .........................
0 .........................
2 .........................
5 .........................
9 .........................
13 .......................
15 .......................

Ambient

97.4 98.7 98.9
97.1 100.6 100.9
95.8 96.4 95.4
93.9 93.7 92.4
93.6 95.5 94.6
94.3 95.3 93.7
96.8 95.8 94.2

97.4 98.7 98.9
97.1 100.6 100.9
95.4 96.6 96.9
92.4 94.3 94.1
95.2 95.6 96.6
91.0 95.0 94.6
92.9 96.3 95.9

8.4. Desorption data.
Samples were prepared by injecting liquid
benzene onto the A section of charcoal tubes.
Samples were prepared that would be equivalent to 0.5, 1.0, and 2.0 ppm for a 10 L air sample.

PERCENT RECOVERY
Sample

0.5 ppm

1.0 ppm

2.0 ppm

1 .........................................
2 .........................................
3 .........................................
4 .........................................
5 .........................................
6 .........................................
X¯= ......................................
SD= ....................................
CV= ....................................
X¯=99.4

99.4
99.5
99.2
99.4
99.2
99.8
99.4
0.22
0.0022

98.8
98.7
98.6
99.1
99.0
99.1
98.9
0.21
0.0021

99.5
99.7
99.8
100.0
99.7
99.9
99.8
0.18
0.0018

8.5. Carbon disulfide.
Carbon disulfide from a number of sources
was analyzed for benzene contamination.
The results are given in the following table.
The benzene contamiant can be removed
with the procedures given in section 4.1.

Sample

μg Benzene/mL

ppm
equivalent (for
10 L air
sample)

Aldrich Lot 83017 ..................................
Baker Lot 720364 ..................................
Baker Lot 822351 ..................................
Malinkrodt Lot WEMP ............................
Malinkrodt Lot WDSJ ............................
Malinkrodt Lot WHGA ............................
Treated CS2 ...........................................

4.20
1.01
1.01
1.74
5.65
2.90
..............

0.13
0.03
0.03
0.05
0.18
0.09
..............

erowe on DSK5CLS3C1PROD with CFR

II. OSHA LABORATORY METHOD NO. 12 FOR
BULK SAMPLES
Analyte: Benzene.
Matrix: Bulk Samples.
Procedure: Bulk Samples are analyzed directly by high performance liquid chromatography (HPLC).
Detection limits: 0.01% by volume.
1. Principle of the method.
1.1. An aliquot of the bulk sample to be
analyzed is injected into a liquid chromatograph.

§ 1910.1028

1.2. The peak area for benzene is determined and compared to areas obtained from
standards.
2. Advantages and disadvantages of the
method.
2.1. The analytical procedure is quick, sensitive, and reproducible.
2.2. Reanalysis of samples is possible.
2.3. Interferences can be circumvented by
proper selection of HPLC parameters.
2.4. Samples must be free of any particulates that may clog the capillary tubing in
the liquid chromatograph. This may require
distilling the sample or clarifying with a
clarification kit.
3. Apparatus.
3.1. Liquid chromatograph equipped with a
UV detector.
3.2. HPLC Column that will separate benzene from other components in the bulk sample being analyzed. The column used for validation studies was a Waters uBondapack C18,
30 cm × 3.9 mm.
3.3. A clarification kit to remove any particulates in the bulk if necessary.
3.4. A micro-distillation apparatus to distill any samples if necessary.
3.5. An electronic integrator or some other
suitable method of measuring peak areas.
3.6. Microliter syringes—10 μL syringe and
other convenient sizes for making standards.
10 μL syringe for sample injections.
3.7. Volumetric flasks, 5 mL and other convenient sizes for preparing standards and
making dilutions.
4. Reagents.
4.1. Benzene, reagent grade.
4.2. HPLC grade water, methyl alcohol, and
isopropyl alcohol.
5. Collection and shipment of samples.
5.1. Samples should be transported in glass
containers with Teflon-lined caps.
5.2. Samples should not be put in the same
container used for air samples.
6. Analysis of samples.
6.1. Sample preparation.
If necessary, the samples are distilled or
clarified. Samples are analyzed undiluted. If
the benzene concentration is out of the
working range, suitable dilutions are made
with isopropyl alcohol.
6.2. HPLC conditions.
The typical operating conditions for the
high performance liquid chromatograph are:
1. Mobile phase—Methyl alcohol/water, 50/
50
1. Analytical wavelength—254 nm
3. Injection size—10 μL
6.3. Measurement of peak area and calibration.
Peak areas are measured by an integrator
or other suitable means. The integrator is
calibrated to report results % in benzene by
volume.
7. Calculations.
Since the integrator is programmed to report results in % benzene by volume in an

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§ 1910.1029

29 CFR Ch. XVII (7–1–09 Edition)

undiluted sample, the following equation is
used:

limit date were obtained by making 10 μL injections of a 0.10% by volume standard.

% Benzene by Volume=A × B

Injection

Area Count

Where:
A=% by volume on report
B=Dilution Factor
(B=1 for undiluted sample)
8. Backup Data.
8.1. Detection limit—Bulk Samples.
The detection limit for the analytical procedure for bulk samples is 0.88 μg, with a coefficient of variation of 0.019 at this level.
This amount provided a chromatographic
peak that could be identifiable in the presence of possible interferences. The detection

1
2
3
4
6

................................................
................................................
................................................
................................................
................................................

45386
44214
43822
44062
42724

X¯=44040.1
SD=852.5
CV=0.019

8.2. Pooled coefficient of variation—Bulk
Samples.
The pooled coefficient of variation for analytical procedure was determined by 50 μL
replicate injections of analytical standards.
The standards were 0.01, 0.02, 0.04, 0.10, 1.0,
and 2.0% benzene by volume.

AREA COUNT (PERCENT)
Injection No.

0.01

0.02

1 ................................................................................................
2 ................................................................................................
3 ................................................................................................
4 ................................................................................................
5 ................................................................................................
6 ................................................................................................
X¯ =
SD =
CV =
¯ V¯ =
C

45386
44241
43822
44062
44006
42724
44040.1
852.5
0.0194
0.017

84737
84300
83835
84381
83012
81957
83703.6
1042.2
0.0125

[52 FR 34562, Sept. 11, 1987, as amended at 54
FR 24334, June 7, 1989; 61 FR 5508, Feb. 13,
1996; 63 FR 1289, Jan. 8, 1998; 63 FR 20099, Apr.
23, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16673,
Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR
75585, Dec. 12, 2008]

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§ 1910.1029

Coke oven emissions.

(a) Scope and application. This section
applies to the control of employee exposure to coke oven emissions, except
that this section shall not apply to
working conditions with regard to
which other Federal agencies exercise
statutory authority to prescribe or enforce standards affecting occupational
safety and health.
(b) Definitions. For the purpose of this
section:
Authorized person means any person
specifically authorized by the employer
whose duties require the person to
enter a regulated area, or any person
entering such an area as a designated
representative of employees for the
purpose of exercising the opportunity
to observe monitoring and measuring
procedures under paragraph (n) of this
section.

0.04
166097
170832
164160
164445
168398
173002
167872
3589.8
0.0213

0.10
448497
441299
443719
444842
442564
443975
444149
2459.1
0.0055

1.0

2.0

4395380
4590800
4593200
4642350
4646430
4646260
4585767
96839.3
0.0211

9339150
9484900
9557580
9677060
9766240

Beehive oven means a coke oven in
which the products of carbonization
other than coke are not recovered, but
are released into the ambient air.
Coke oven means a retort in which
coke is produced by the destructive distillation or carbonization of coal.
Coke oven battery means a structure
containing a number of slot-type coke
ovens.
Coke oven emissions means the benzene-soluble fraction of total particulate matter present during the destructive distillation or carbonization of
coal for the production of coke.
Director means the Director, National
Institute for Occupational Safety and
Health, U.S. Department of Health,
Education, and Welfare, or his or her
designee.
Emergency means any occurence such
as, but not limited to, equipment failure which is likely to, or does, result in
any massive release of coke oven emissions.
Existing coke oven battery means a
battery in operation or under construction on January 20, 1977, and which is
not a rehabilitated coke oven battery.

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Jkt 217114

PO 00000

Frm 00264

Fmt 8010

9564986
166233
0.0174

Sfmt 8010

Y:\SGML\217114.XXX

217114