Machine Safety
Chapter 296-806, WAC |
Effective
Date: 01/01/05 |
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PUSHER-BAR CONVEYORS
WAC 296-806-42054
Guard pusher-bar conveyors
You must
- Provide a guard when hazards exist at each
of these points:
- – At the discharge point where the
bar passes through the bed
- – Where there's
a shear point between the return pusher bar and a frame
member
ROLLER CONVEYORS
WAC 296-806-42056
Prohibit walking on roller-type conveyors
You must
- Prohibit employees from walking on the rolls
of roller-type conveyors.
- Tread plates or other types of walkways can
be used between the rollers as a walking surface for operators
when performing their duties.
WAC 296-806-42058
Use speed controls for roller and wheel conveyors
You must
- Avoid safety hazards created by unit or package
speeds by one of the following methods:
- – Limiting the length of the sloped
run
- – Using speed retarders or brakes
- – Other means of providing speed
control
- Make sure rollers and wheels are free running
to prevent locked wheels from steering or pulling materials
to one side or off the conveyor.
WAC 296-806-42060
Safeguard belt-driven live roller conveyors
You must
- Guard belt and roller nip points by one
of the following methods:
- – Space load-carrying rollers to
prevent access to the belt and roller nip points.
- – Insert rods or plates between
the rollers to prevent access to the belt and roller nip
points.
- – Use rollers that pop out when
something contacts the nip point.
- – Distance safeguarding found in:
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Reference:
- For nip points and sheer hazards on
power-driven (live) roller conveyors see Guard nip
points on belt conveyors, WAC
296-806-42028.
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SCREW CONVEYORS
WAC 296-806-42062
Guard screw conveyors
You must
- Enclose the rotating screw to prevent contact
with the shear points where it passes the sides of the trough
or casing
- Guard screw conveyors requiring an open housing
by using one of the following:
- Construct feed openings for shovel, front-end
loader, or other manual or mechanical equipment so that the
conveyor screw is covered by a grating.
- – If the nature of the material
is such that a grating can't be used, then the exposed section
of the conveyor must be guarded by a railing and warning
signs.
SKIP HOISTS
WAC 296-806-42064
Provide slack-cable switches on hoists
You must
- Provide and arrange slack cable switches to
cut power to the drive and set the brake when the skip or counterweight
hoisting ropes either:
- – Develop slack
or
- – Lose tension due to sticking
in the guides, over travel, or for any other reason.
WAC 296-806-42066
Block the skip bucket and counterweight guides
You must
- Make sure the skip bucket and counterweight
are blocked in their guides when the brake or any part of the
drive train between the brake and the drum shaft are being repaired
or replaced.
WAC 296-806-42068
Protect against wire rope coming off sheaves
You must
- Fit all sheaves with sheave guards to prevent
the wire rope from coming off under slack cable or similar conditions
SLAT AND ROLLER-SLAT CONVEYORS
WAC 296-806-42070
Safeguard slat and roller-slat conveyors
You must
- Provide either of these
safeguards at the tail end of a slat conveyor if the slats are
above the centerline of the chain:
- – A guard over the hazardous tail
end
or
- – Warning signs if guards are impractical
because of material flowing over the tail sprocket
- Provide either of these
safeguards when there's a gap between the slats wide enough
to permit access to cross members below the slats:
- – A continuous pan under the slats
or
- – Keep all cross members a safe
distance from the slats
TOWED CONVEYORS
WAC 296-806-42072
Provide a safe method for disengaging the
tow pin
You must
- Provide a method for the operator to disengage
the tow pin from a conveyor pusher without being in front of
the cart.
WAC 296-806-42074
Protect employees from moving carts on towed
conveyors
You must
- Make sure runaway carts are unable
to exit ramps and enter work areas.
- Have a barrier of sufficient strength and
height on ramps with pedestrian or traffic aisles to prevent
a runaway cart from entering the aisle.
- Have signs warning employees not to enter
ramps that don't have pedestrian or traffic aisles.
WAC 296-806-42076
Provide clearances and warnings for carts
on towed conveyors
You must
- Provide clearance space for personnel in
all of the following:
- – Between the sides of carts
- – Between any load overhanging the
side of a cart
- – Any fixed or moving object
- Identify the cart path with floor stripes
that are:
- – Parallel to the cart path
- – Arranged so one line is on each
side of the path
- – Located a safe distance from the
edge of the cart or overhanging load
- Mark reduced clearance areas with appropriate
warning signs.
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Note:
- An example of a reduced clearance area
is an area where a cart goes through a wall opening.
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You must
- Place an appropriate warning on those areas
where a cart may unexpectedly change direction, such as switching
off the main line into a transfer conveyor or a spur.
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Note:
- An example of an appropriate warning
would be to use diagonal stripes on the floor between
clearance lines.
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You must
- Install a sign, signal, or other warning
where carts start automatically.
WAC 296-806-42078
Mark projections above the floor
You must
- Mark the area around projections above the
floor with appropriate diagonal stripes, warning signs, or both.
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Note:
- This is especially important if projections
above the floor are unpredictable or occur intermittently.
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