This rule is to cover minimum standards for the safe
installation, operation and maintenance of all types of conveying machinery and
equipment, which includes belt, bucket, chain, roller, reciprocating or
oscillating, screw, pneumatic, and flight conveyors or conveying systems. In
the event these orders do not cover a specific hazardous condition, the ANSI
standard B-20.1, 1996 shall be used as a guide.
A. Guarding.
1. Driving mechanisms of conveying equipment
shall be enclosed by housing or guards where it is possible for workers to come
in contact with gears, chain or belt drives or moving shafts. The guards shall
be constructed so no part of the body or clothing can contact the driving
mechanism.
2. Head pulleys, tail
pulleys, take up, counterweights, sprockets, sheaves, drums, blocks, etc.,
shall be enclosed with guards or the area blocked off with rails or fence so
workers cannot come in contact with moving parts.
3. Bucket elevators shall be enclosed in a
housing or the area blocked off so no hazard exists from falling
material.
4. Screw conveyors,
troughs, or box openings shall have covers, grating or guard rails to prevent
workers from coming in contact with the moving conveyor.
5. Conveyors passing over work areas, aisles
or walkways where workers are exposed shall be covered underneath to eliminate
hazard from falling material or personal contact.
6. Openings to hoppers, chutes or other
discharge points where workers may be exposed shall be guarded by railings,
toeboards, baffleplates, chains, temporary covers and front and sides high
enough to prevent workers falling into them and material being discharged from
striking them.
7. Platforms with
side rails shall be constructed on trippers where a worker is required to ride
or climb on the tripper to operate the controls so he cannot slip off or come
in contact with the moving machinery. If a platform is not required, levers and
controls shall be located so the worker can safely operate the tripper without
coming in contact with the moving machinery.
B. Inspection and Maintenance.
1. Periodic inspection of the entire
conveying mechanism shall be made for worn parts, defective couplings, loose
belts, chains and defective safety devices such as brakes, backstops, overload
releases, guards, etc.
2. Such
inspection shall be made while the equipment is stopped and locked out except
where the inspector can stand completely in the clear of any moving
parts.
3. Lubrication of machine
parts shall not be done while equipment is operating unless grease and oil
fittings are equipped with extensions which permit such lubrication from a
position where the worker cannot come in contact with the moving
machinery.
C. Walkways,
Platforms, Balconies
1. Where conveyors must
be crossed over during operation, a walkway with stairs, platform, handrails
and toeboards shall be constructed and conspicuously marked with a sign. Where
walkways, ramps or stairways are located adjacent to open belt or pan
conveyors, they shall be at least 20 inches in width and there shall be three
feet clearance from the outside of the passageway and the moving conveyor. All
stairways shall have handrails adjacent to the conveyor to prevent workers who
may stumble from falling into the conveyor.
2. Where workers must cross under a conveyor,
crossunders shall be plainly marked as the only passageways. The passageway
shall be covered to prevent contact with moving parts or material falling off
the conveyor.
D. Brakes
and Backstops.
On conveyors where reversing or a runaway might occur under
load in case of power failure, an anti- runaway or backstop device or automatic
brake shall be provided or guard rails installed to prevent anyone from being
in the area where the falling load could strike him.
E. Dust control.
1. Dust control equipment, provided at
transfer points, crushers or such as sprays or exhaust hoods shall be wherever
a dust condition exists which may be a health hazard to workers or a fire or
explosion hazard.
2. Where the
installation of dust control equipment is not practical, workers shall be
provided with approved respiratory devices.
F. Fire Protection
1. Housekeeping along conveying systems shall
be maintained in a manner that will prevent fires.
2. Where conveying equipment fire may present
a hazard to workers or building, emergency fire fighting equipment shall be
provided and identified and strategically located to control any outbreak of
fire. Equipment selection should consider the control of electrical fires,
burning belting and conveyor structures, materials being handled, adjacent
materials, etc.
3. Workers
operating conveying equipment shall be knowledgeable in the use of the fire
protection equipment furnished.
4.
Where conveying equipment is located in building or tunnel enclosures where men
are working, emergency fire exits shall be provided and identified.
5. All fire fighting equipment, alarm
stations, etc., must be identified and readily accessible and free of
obstructions.
G.
Illumination.
Sufficient lighting to see the equipment clearly shall be
provided at floor level, head and tail pulleys, operating stations and along
conveyor systems which must be inspected - 5 to 10-foot candles of light meet
this requirement.
H.
Electrical.
1. Power and control circuits for
conveying equipment shall be installed so as to minimize the possibility of
electric shock or fire hazard. This shall include grounding. After the
effective date of these orders, new equipment shall be installed in accordance
with the current edition of the National Electric Code.
2. Power and control circuits shall not be
enclosed in the same conduit lines or junction boxes.
3. All starting and stopping devices shall be
clearly marked and the immediate area kept clear of obstructions to permit
ready access.
4. All conveyor
switch boxes shall be identified indicating the voltage and the equipment
served.
5. Electrical installations
in explosive areas shall meet the requirements, as applicable, of the National
Electrical Code, Chapter 500.
6.
The installation of electrical emergency conveyor stops, such as pull cables,
or push buttons, is recommended where workers are manually loading or unloading
or doing cleanup work while equipment is operating.
7. Overload protective devices are
recommended on conveying equipment power circuits to prevent damage or
fire.
I. Safe Operating
Rules.
1. Manually loaded vertical or highly
inclined conveyors shall have a sign at the loading point designating the load
capacity.
2. No riding shall be
permitted on any conveyor not specifically designed and approved to convey
workers.
3. Repairs to conveyors or
related equipment shall not be done while the equipment is operating. When
stopped for repairs, servicing, cleaning, removing overloads, etc., the
controls shall be locked or tagged out.
4. No safety device, guard, overload, cutout,
brake, etc., shall be removed from a conveyor and the conveyor placed in
operation without the device being reinstalled. Where permanent guards at
hazardous points must be left off, the area shall be laced off with temporary
boards, etc., if the conveyor is placed in operation other than for
testing.
5. Workers working around
or operating conveyors shall be advised of the location of the starting and
stopping devices and instructed how to use them to stop the conveyor in an
emergency.