WAC 296-806-420 Conveyors

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GENERAL REQUIREMENTS FOR CONVEYORS

WAC 296-806-42002

Follow these requirements for conveyors

You must

• Construct, operate, and maintain all conveyors according to this chapter and the American National Standards Institute (ANSI) B20.1-1957.
• Make sure all new conveyors constructed after January 1, 2005, meet the requirements of the American Society of Mechanical Engineers (ASME)
  B20.1-1996.

WAC 296-806-42004

Provide emergency stops on conveyors

• Make sure each conveyor has an emergency stopping device such as an emergency stop button, pull cord, or similar device.
• Make sure each emergency stopping device meets all of the following requirements. They must:
  • – Stop the conveyor a safe distance from the hazard
  • – Be easily identified
  • – Directly control that conveyor
  • – Require a manual reset
  • – Not be overridden from another location
  • – Not require other equipment to be stopped in order to stop the conveyor
• Make sure where there's the possibility of an employee falling onto a conveyor, that the emergency stopping device for conveyors feeding or dumping into a hazardous machine such as a barker, saw, hog, or chipper is at least one of the following:
  • – Under the continuous control of an operator who can't fall onto the conveyor and has full view of the material entrance
    or
  • – Located where it can be reached from a sitting position on the conveyor where it feeds or dumps into the hazardous machine

WAC 296-806-42006

Label conveyor controls

• Clearly label the function of each conveyor control.

WAC 296-806-42008

Prohibit riding on conveyors

• Prohibit employees from riding on conveyors.

WAC 296-806-42010

Provide safe access to conveyors

• Provide a way to safely inspect and maintain conveyors located more than 7 feet from the floor.

WAC 296-806-42012

Provide backstop or anti-runaway devices on incline, decline, or vertical conveyors

• Make sure all incline, decline, or vertical conveyors use backstop or anti-runaway devices when there's a danger of conveyor reversal or runaway.

WAC 296-806-42014

Make only safe alterations to conveyors

• Make sure, when making conveyor alterations, that you don't affect safety characteristics such as emergency stop controls, guards, or the incline of the conveyor, if such changes would create a danger to workers.

WAC 296-806-42016

Inspect and replace worn conveyor parts

• Carefully inspect and replace any conveyor part that shows signs of significant wear before it becomes a hazard.

WAC 296-806-42018

Follow these requirements for replacing conveyor parts

• Make sure replacement conveyor parts are equal to or exceed the manufacturer’s specifications.

WAC 296-806-42020

Follow these requirements for spill guards

• Install protective or spill guards wherever conveyors pass next to or over working areas or passageways.
  • – These guards must be designed to catch and hold any materials that may become dislodged or fall off.

  Reference: For specific requirements when conveyors pass over emergency exit routes, see Exit Routes, WAC 296-800-310.

WAC 296-806-42022

Provide pedestrian overpasses for conveyors

• Provide a pedestrian overpass covering the full width of a passageway if one of these conditions exists:
  • – The working strand of a conveyor crosses within 3 feet of floor level
  • – Workers must step over the strand and trough at or below floor level
• Provide a pedestrian overpass where workers can't pass under the conveyor safely
• – The sides of the crossing platform must have standard railings if one of the following exists:
  • The overpass is more than 4 feet high
  • The conveyor feeds a dangerous machine such as saws, chippers, hogs, or galvanizing tanks

Reference: For guardrail requirements see Railing, Toeboards, and Cover Specifications, WAC 296-24-75011.

WAC 296-806-42024

Guard openings to hoppers and chutes

• Guard all openings to hoppers, chutes, and elevator-type conveyors to prevent workers from:
  • – Falling or stepping into them
  • – Making any kind of bodily contact with conveyors

  Note: Grating provided at floor level with no openings larger than 2 inches (50mm) that's strong enough to withstand any load of personnel or trucks that may be imposed upon it, is acceptable guarding.

You must

• Do all of the following when dumping operations use chutes or hoppers that are flush with the floor and their use can't be guarded:
  • – Place a temporary guardrail around ground or floor-level hoppers when dumping operations are not in progress.
  • – Post warning signs in a conspicuous location alerting personnel to the presence of an open pit in order to protect employees when dumping operations are in progress.

  Reference: For guardrail requirements see Railing, Toeboards, and Cover Specifications, WAC 296-24-75011.

WAC 296-806-42026

Install guideposts

• Install guideposts to direct employees driving trucks, loaders, or other equipment to the pit, hopper, or chute.

BELT CONVEYORS

WAC 296-806-42028

Guard nip points on belt conveyors

Illustration 420-1
RETURN BELT IDLERS

• Place nip point guards at all of these points:
  • – Where the belt wraps around the pulley
  • – At terminals, take-ups, and snub rollers where the belt changes directions at transfers and deflectors
  • – At the discharge end
  • – At other points where workers may be injured by nip or shear points

  Note: The practice of applying a belt dressing or other foreign material to a rotating drive pulley or a conveyor belt is hazardous and should be avoided.

WAC 296-806-42030

Install emergency stop controllers on overland belt conveyors

• Install permanent emergency pull cords or similar emergency stop controllers at points where workers are normally stationed along overland belt conveyors.

  Note: Personnel that patrol overland belt conveyors may use portable emergency stop controllers instead of permanently installed pull cords and push-button stations.

WAC 296-806-42032

Install belt conveyor overpasses

• Install a pedestrian overpass or underpass along the sides of long overland belt conveyors, where there's the most foot traffic.
  • – The distance between overpasses shouldn't exceed 300 meters or 1,000 feet.

CHAIN CONVEYORS

WAC 296-806-42034

Safeguard chain conveyors

• Provide safeguards for drive, tail, and idler sprocket pulleys where the chain creates a nip or shear point

WAC 296-806-42036

Guard return strands on chain conveyors

• Provide a way to catch and support the ends of a chain that break over a passageway.
• Provide a strong enough trough to carry the weight from a broken chain on conveyors when return strands operate within 7 feet of the floor.

WAC 296-806-42038

Guard chain conveyors that are used as a transfer mechanism

• Guard chain conveyors whose moving chains can't be enclosed without impairing their function by one of the following methods:
  • – Distance as required in Make sure safeguarding by distance meets these requirements, WAC 296-806-20056
  • – Personnel barriers
  • – Warning signs where personnel barriers aren't practical

  Note: Chain conveyors with moving chains that can't be enclosed include those: – Mounted within another conveyor – Raised and lowered as a transfer mechanism

ELEVATOR CONVEYORS

WAC 296-806-42040

Prevent material from falling off of elevator conveyors

• Install strong guards, screens, or barricades to prevent material from falling in any direction into the shaft way of elevator-type conveyors, except at loading and unloading areas.
• Install automatic shaft way gates or suitable barriers at each floor level where material is loaded or unloaded.

INCLINED RECIPROCATING CONVEYORS (SHAKERS)

WAC 296-806-42042

Provide protection where employees must load shakers

• Provide standard guardrails or snap chains along loading sides of the shaker where personnel must load or unload material.
  • – Snap chains must be at least 39 inches high at their lowest point.
• Make sure controls are located so the conveyor can't be started by an employee on the moving part of the conveyor.

WAC 296-806-42044

Provide grating over silo and bunker openings for shuttle conveyors

• Provide grating with openings to match the size of the material being discharged into silos or bunkers. Make sure openings are:
  • – Small enough so that workers can't fall through
  • – Protected by other effective means if the material size requires openings large enough for a worker to fall through

MOBILE CONVEYORS

WAC 296-806-42046

Guard wheels and rails on mobile conveyors

• Install sweeps in front of the nip points created by the wheels and rails to deflect objects that could derail the conveyor.

WAC 296-806-42048

Prevent hazardous motion on mobile conveyors

• Make sure mobile conveyors have at least one of the following to prevent hazardous motion:
  • – Brakes
  • – Rail clamps
  • – Other position-locking devices
• Provide limit switches that will stop travel when exceeding the design limits of
  rail-mounted mobile conveyors
• Provide rail stops to keep the conveyor from traveling past its designed end location.

WAC 296-806-42050

Provide a detector for mobile conveyors

• Provide a detector to stop conveyor movement when the operation creates a danger of running into a stockpile or other obstacle.

WAC 296-806-42052

Provide safe access on mobile conveyors

• Make sure that access stairways, ladders, and platforms are designed and located to avoid the shear or nip point hazards of the conveyor and moving machinery.

-Continued-