29 CFR 1910.217(g)

§ 1910.217

29 CFR Ch. XVII (7–1–08 Edition)

to come in contact with the roll bite or
be caught between a roll and an adjacent object, then, provided such elements are made a fixed part of a calender, safety control devices listed in
paragraph (c) of this section shall not
apply.
(e) Trip and emergency switches. All
trip and emergency switches shall not
be of the automatically resetting type,
but shall require manual resetting.
(f) Stopping limits—(1) Determination of
distance of travel. All measurements on
mills and calenders shall be taken with
the rolls running empty at maximum
operating speed. Stopping distances
shall be expressed in inches of surface
travel of the roll from the instant the
emergency stopping device is actuated.
(2) Stopping limits for mills. All mills
irrespective of the size of the rolls or
their arrangement (individually or
group-driven) shall be stopped within a
distance, as measured in inches of surface travel, not greater than 11⁄2 percent of the peripheral no-load surface
speeds of the respective rolls as determined in feet per minute.
(3) Stopping limits for calenders. (i) All
calenders, irrespective of size of the
rolls or their configuration, shall be
stopped within a distance, as measured
in inches of surface travel, not greater
than 13⁄4 percent of the peripheral noload surface speeds of the respective
calender rolls as determined in feet per
minute.
(ii) Where speeds above 250 feet per
minute as measured on the surface of
the drive roll are used, stopping distances of more than 13⁄4 percent are
permissible. Such stopping distances
shall be subject to engineering determination.

yshivers on PROD1PC62 with CFR

[39 FR 23502, June 27, 1974, as amended at 49
FR 5323, Feb. 10, 1984; 61 FR 9240, Mar. 7, 1996]

§ 1910.217 Mechanical power presses.
(a) General requirements.
(1)–(3) [Reserved]
(4) Reconstruction and modification. It
shall be the responsibility of any person reconstructing, or modifying a mechanical power press to do so in accordance with paragraph (b) of this section.
(5) Excluded machines. Press brakes,
hydraulic and pneumatic power presses, bulldozers, hot bending and hot
metal presses, forging presses and ham-

mers, riveting machines and similar
types of fastener applicators are excluded from the requirements of this
section.
(b) Mechanical power press guarding
and construction, general—(1) Hazards to
personnel associated with broken or falling machine components. Machine components shall be designed, secured, or
covered to minimize hazards caused by
breakage, or loosening and falling or
release of mechanical energy (i.e. broken springs).
(2) Brakes. Friction brakes provided
for stopping or holding a slide movement shall be inherently self-engaging
by requiring power or force from an external source to cause disengagement.
Brake capacity shall be sufficient to
stop the motion of the slide quickly
and capable of holding the slide and its
attachments at any point in its travel.
(3) Machines using full revolution positive clutches. (i) Machines using full
revolution clutches shall incorporate a
single-stroke mechanism.
(ii) If the single-stroke mechanism is
dependent upon spring action, the
spring(s) shall be of the compression
type, operating on a rod or guided
within a hole or tube, and designed to
prevent interleaving of the spring coils
in event of breakage.
(4) Foot pedals (treadle). (i) The pedal
mechanism shall be protected to prevent unintended operation from falling
or moving objects or by accidental
stepping onto the pedal.
(ii) A pad with a nonslip contact area
shall be firmly attached to the pedal.
(iii) The pedal return spring(s) shall
be of the compression type, operating
on a rod or guided within a hole or
tube, or designed to prevent interleaving of spring coils in event of
breakage.
(iv) If pedal counterweights are provided, the path of the travel of the
weight shall be enclosed.
(5) Hand operated levers. (i) Handlever-operated power presses shall be
equipped with a spring latch on the operating lever to prevent premature or
accidental tripping.
(ii) The operating levers on handtripped presses having more than one
operating station shall be interlocked

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yshivers on PROD1PC62 with CFR

Occupational Safety and Health Admin., Labor
to prevent the tripping of the press except by the ‘‘concurrent’’ use of all levers.
(6) Two-hand trip. (i) A two-hand trip
shall have the individual operator’s
hand controls protected against unintentional operation and have the individual operator’s hand controls arranged by design and construction and/
or separation to require the use of both
hands to trip the press and use a control arrangement requiring concurrent
operation of the individual operator’s
hand controls.
(ii) Two-hand trip systems on full
revolution clutch machines shall incorporate an antirepeat feature.
(iii) If two-hand trip systems are used
on multiple operator presses, each operator shall have a separate set of controls.
(7) Machines using part revolution
clutches. (i) The clutch shall release
and the brake shall be applied when the
external clutch engaging means is removed, deactivated, or deenergized.
(ii) A red color stop control shall be
provided with the clutch/brake control
system. Momentary operation of the
stop control shall immediately deactivate the clutch and apply the brake.
The stop control shall override any
other control, and reactuation of the
clutch shall require use of the operating (tripping) means which has been
selected.
(iii) A means of selecting Off, ‘‘Inch,’’
Single Stroke, and Continuous (when
the continuous function is furnished)
shall be supplied with the clutch/brake
control to select type of operation of
the press. Fixing of selection shall be
by means capable of supervision by the
employer.
(iv) The ‘‘Inch’’ operating means
shall be designed to prevent exposure
of the workers hands within the point
of operation by:
(a) Requiring the concurrent use of
both hands to actuate the clutch, or
(b) Being a single control protected
against accidental actuation and so located that the worker cannot reach
into the point of operation while operating the single control.
(v) Two-hand controls for single
stroke shall conform to the following
requirements:

§ 1910.217

(a) Each hand control shall be protected against unintended operation
and arranged by design, construction,
and/or separation so that the concurrent use of both hands is required to
trip the press.
(b) The control system shall be designed to permit an adjustment which
will require concurrent pressure from
both hands during the die closing portion of the stroke.
(c) The control system shall incorporate an antirepeat feature.
(d) The control systems shall be designed to require release of all operators’ hand controls before an interrupted stroke can be resumed. This requirement pertains only to those single-stroke, two-hand controls manufactured and installed on or after August
31, 1971.
(vi) [Reserved]
(vii) Controls for more than one operating station shall be designed to be
activated and deactivated in complete
sets of two operator’s hand controls per
operating station by means capable of
being supervised by the employer. The
clutch/brake control system shall be
designed and constructed to prevent
actuation of the clutch if all operating
stations are bypassed.
(viii) Those clutch/brake control systems which contain both single and
continuous functions shall be designed
so that completion of continuous circuits may be supervised by the employer. The initiation of continuous
run shall require a prior action or decision by the operator in addition to the
selection of Continuous on the stroking
selector, before actuation of the operating means will result in continuous
stroking.
(ix) If foot control is provided, the selection method between hand and foot
control shall be separate from the
stroking selector and shall be designed
so that the selection may be supervised
by the employer.
(x) Foot operated tripping controls, if
used, shall be protected so as to prevent operation from falling or moving
objects, or from unintended operation
by accidental stepping onto the foot
control.
(xi) The control of air-clutch machines shall be designed to prevent a

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yshivers on PROD1PC62 with CFR

§ 1910.217

29 CFR Ch. XVII (7–1–08 Edition)

significant increase in the normal stopping time due to a failure within the
operating value mechanism, and to inhibit further operation if such failure
does occur. This requirement shall
apply only to those clutch/brake airvalve controls manufactured and installed on or after August 31, 1971, but
shall not apply to machines intended
only for continuous, automatic feeding
applications.
(xii) The clutch/brake control shall
incorporate an automatic means to
prevent initiation or continued activation of the Single Stroke or Continuous functions unless the press drive
motor is energized and in the forward
direction.
(xiii) The clutch/brake control shall
automatically deactivate in event of
failure of the power or pressure supply
for the clutch engaging means. Reactivation of the clutch shall require restoration of normal supply and the use
of the tripping mechanism(s).
(xiv) The clutch/brake control shall
automatically deactivate in event of
failure of the counterbalance(s) air
supply. Reactivation of the clutch shall
require restoration of normal air supply and use of the tripping mechanism(s).
(xv) Selection of bar operation shall
be by means capable of being supervised by the employer. A separate
pushbutton shall be employed to activate the clutch, and the clutch shall be
activated only if the driver motor is
deenergized.
(8) Electrical. (i) A main power disconnect switch capable of being locked
only in the Off position shall be provided with every power press control
system.
(ii) The motor start button shall be
protected against accidental operation.
(iii) All mechanical power press controls shall incorporate a type of drive
motor starter that will disconnect the
drive motor from the power source in
event of control voltage or power
source failure, and require operation of
the motor start button to restart the
motor when voltage conditions are restored to normal.
(iv) All a.c. control circuits and solenoid value coils shall be powered by
not more than a nominal 120-volt a.c.
supply obtained from a transformer

with an isolated secondary. Higher
voltages that may be necessary for operation of machine or control mechanisms shall be isolated from any control mechanism handled by the operator, but motor starters with integral
Start-Stop buttons may utilize line
voltage control. All d.c. control circuits shall be powered by not more
than a nominal 240-volt d.c. supply isolated from any higher voltages.
(v) All clutch/brake control electrical
circuits shall be protected against the
possibility of an accidental ground in
the control circuit causing false operation of the press.
(vi) Electrical clutch/brake control
circuits shall incorporate features to
minimize the possibility of an unintended stroke in the event of the failure of a control component to function
properly,
including
relays,
limit
switches, and static output circuits.
(9) Slide counterbalance systems. (i)
Spring counterbalance systems when
used shall incorporate means to retain
system parts in event of breakage.
(ii) Spring counterbalances when
used shall have the capability to hold
the slide and its attachments at
midstroke, without brake applied.
(iii) Air counterbalance cylinders
shall incorporate means to retain the
piston and rod in case of breakage or
loosening.
(iv) Air counterbalance cylinders
shall have adequate capability to hold
the slide and its attachments at any
point in stroke, without brake applied.
(v) Air counterbalance cylinders shall
incorporate means to prevent failure of
capability (sudden loss of pressure) in
event of air supply failure.
(10) Air controlling equipment. Air controlling equipment shall be protected
against foreign material and water entering the pneumatic system of the
press. A means of air lubrication shall
be provided when needed.
(11) Hydraulic equipment. The maximum anticipated working pressures in
any hydraulic system on a mechanical
power press shall not exceed the safe
working pressure rating of any component used in that system.
(12) Pressure vessels. All pressure vessels used in conjunction with power
presses shall conform to the American
Society of Mechanical Engineers Code

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§ 1910.217

29 CFR Ch. XVII (7–1–08 Edition)

TABLE O–10—Continued
[In inches]
Distance of opening from point of operation hazard
51⁄2 to 61⁄2 ............................................................
61⁄2 to 71⁄2 ............................................................
71⁄2 to 121⁄2 ..........................................................
121⁄2 to 151⁄2 ........................................................
151⁄2 to 171⁄2 ........................................................
171⁄2 to 311⁄2 ........................................................

Maximum
width of
opening
⁄
7⁄8
11⁄4
11⁄2
17⁄8
21⁄8
34

yshivers on PROD1PC62 with CFR

This table shows the distances that guards
shall be positioned from the danger line in
accordance with the required openings.

(g) Reports of injuries to employees operating mechanical power presses. (1) The
employer shall, within 30 days of the
occurrence, report to either the Director of the Directorate of Safety Standards Programs, OSHA, U.S. Department of Labor, Washington, D.C. 20210,
or the State agency administering a
plan approved by the Assistant Secretary of Labor for Occupational Safety and Health, all point of operation
injuries to operators or other employees. The following information shall be
included in the report:
(i) Employer’s name, address and location of the workplace (establishment).
(ii) Employee’s name, injury sustained, and the task being performed
(operation, set-up, maintenance, or
other).
(iii) Type of clutch used on the press
(full revolution, part revolution, or direct drive).
(iv) Type of safeguard(s) being used
(two hand control, two hand trip, pullouts, sweeps, or other). If the safeguard
is not described in this section, give a
complete description.
(v) Cause of the accident (repeat of
press, safeguard failure, removing
stuck part or scrap, no safeguard provided, no safeguard in use, or other).
(vi) Type of feeding (manual with
hands in dies or with hands out of dies,
semiautomatic, automatic, or other).
(vii) Means used to actuate press
stroke (foot trip, foot control, hand
trip, hand control, or other).
(viii) Number of operators required
for the operation and the number of operators provided with controls and
safeguards.
(h) Presence sensing device initiation
(PSDI)—(1) General. (i) The require-

ments of paragraph (h) shall apply to
all part revolution mechanical power
presses used in the PSDI mode of operation.
(ii) The relevant requirements of
paragraphs (a) through (g) of this section also shall apply to all presses used
in the PSDI mode of operation, whether or not cross referenced in this paragraph (h). Such cross-referencing of
specific requirements from paragraphs
(a) through (g) of this section is intended only to enhance convenience
and understanding in relating to the
new provisions to the existing standard, and is not to be construed as limiting the applicability of other provisions in paragraphs (a) through (g) of
this section.
(iii) Full revolution mechanical
power presses shall not be used in the
PSDI mode of operation.
(iv) Mechanical power presses with a
configuration which would allow a person to enter, pass through, and become
clear of the sensing field into the hazardous portion of the press shall not be
used in the PSDI mode of operation.
(v) The PSDI mode of operation shall
be used only for normal production operations. Die-setting and maintenance
procedures shall comply with paragraphs (a) through (g) of this section,
and shall not be done in the PSDI
mode.
(2) Brake and clutch requirements. (i)
Presses with flexible steel band brakes
or with mechanical linkage actuated
brakes or clutches shall not be used in
the PSDI mode.
(ii) Brake systems on presses used in
the PSDI mode shall have sufficient
torque so that each average value of
stopping times (Ts) for stops initiated
at approximately 45 degrees, 60 degrees,
and 90 degrees, respectively, of crankshaft angular position, shall not be
more than 125 percent of the average
value of the stopping time at the top
crankshaft position. Compliance with
this requirement shall be determined
by using the heaviest upper die to be
used on the press, and operating at the
fastest press speed if there is speed selection.
(iii) Where brake engagement and
clutch release is effected by spring action, such spring(s) shall operate in
compression on a rod or within a hole

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yshivers on PROD1PC62 with CFR

Occupational Safety and Health Admin., Labor
or tube, and shall be of non-interleaving design.
(3) Pneumatic systems. (i) Air valve
and air pressure supply/control.
(A) The requirements of paragraphs
(b)(7)(xiii), (b)(7)(xiv), (b)(10), (b)(12)
and (c)(5)(iii) of this section apply to
the pneumatic systems of machines
used in the PSDI mode.
(B) The air supply for pneumatic
clutch/brake control valves shall incorporate a filter, an air regulator, and,
when necessary for proper operation, a
lubricator.
(C) The air pressure supply for
clutch/brake valves on machines used
in the PSDI mode shall be regulated to
pressures less than or equal to the air
pressure used when making the stop
time measurements required by paragraph (h)(2)(ii) of this section.
(ii) Air counterbalance systems.
(A) Where presses that have slide
counterbalance systems are used in the
PSDI mode, the counterbalance system
shall also meet the requirements of
paragraph (b)(9) of this section.
(B) Counterbalances shall be adjusted
in accordance with the press manufacturer’s recommendations to assure correct counterbalancing of the slide attachment (upper die) weight for all operations performed on presses used in
the PSDI mode. The adjustments shall
be made before performing the stopping time measurements required by
paragraphs (h)(2)(ii), (h)(5)(iii), and
(h)(9)(v) of this section.
(4) Flywheels and bearings. Presses
whose designs incorporate flywheels
running on journals on the crankshaft
or back shaft, or bull gears running on
journals mounted on the crankshaft,
shall be inspected, lubricated, and
maintained as provided in paragraph
(h)(10) of this section to reduce the possibility of unintended and uncontrolled
press strokes caused by bearing seizure.
(5) Brake monitoring. (i) Presses operated in the PSDI mode shall be
equipped with a brake monitor that
meets the requirements of paragraphs
(b)(13) and (b)(14) of this section. In addition, the brake monitor shall be adjusted during installation certification
to prevent successive stroking of the
press if increases in stopping time
cause an increase in the safety distance

§ 1910.217

above that required by paragraph
(h)(9)(v) of this section.
(ii) Once the PSDI safety system has
been certified/validated, adjustment of
the brake monitor shall not be done
without prior approval of the validation organization for both the brake
monitor adjustment and the corresponding adjustment of the safety
distance. The validation organization
shall in its installation validation,
state that in what circumstances, if
any, the employer has advance approval for adjustment, when prior oral
approval is appropriate and when prior
approval must be in writing. The adjustment shall be done under the supervision of an authorized person whose
qualifications include knowledge of
safety distance requirements and experience with the brake system and its
adjustment. When brake wear or other
factors extend press stopping time beyond the limit permitted by the brake
monitor, adjustment, repair, or maintenance shall be performed on the
brake or other press system element
that extends the stopping time.
(iii) The brake monitor setting shall
allow an increase of no more than 10
percent of the longest stopping time
for the press, or 10 milliseconds, whichever is longer, measured at the top of
the stroke.
(6) Cycle control and control systems. (i)
The control system on presses used in
the PSDI mode shall meet the applicable requirements of paragraphs (b)(7),
(b)(8), (b)(13), and (c)(5) of this section.
(ii) The control system shall incorporate a means of dynamically monitoring for decoupling of the rotary position indicating mechanism drive
from the crankshaft. This monitor
shall stop slide motion and prevent
successive press strokes if decoupling
occurs, or if the monitor itself fails.
(iii) The mode selection means of
paragraph (b)(7)(iii) of this section
shall have at least one position for selection of the PSDI mode. Where more
than one interruption of the light sensing field is used in the initiation of a
stroke, either the mode selection
means must have one position for each
function, or a separate selection means
shall be provided which becomes operable when the PSDI mode is selected.

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