Rev. November 10, 2020
The introduction of conveyor belts into the industry brought with it the hazards of moving parts at main pulleys, the possibility of being pulled into the belt at idlers while walking nearby, and while working near the belt or on the belt and the machinery.
Since that time, regulations have increased to cover all areas where people can get pulled in and injured. These items were covered by the 1959 regulations. The 1971 Handbook of Requirements Governing the Operation of Mines covered the subject of pull cords in section 250(l)(d) as follows:
"Any accessible section of an electrically driven belt conveyor shall be provided with pull-cords to stop the conveyor in an emergency and such pull-cords shall reach from the head pulley to the tail pulley and all controls operated by these cords shall be of the manual-reset type."
Conveyor Safety Standard
The main hazards involve belts. This moving component can catch body parts in pinch points and lead to entanglement and crushing.
Common types of accidents with conveyors involve personnel struck by objects or caught in equipment. The majority of these accidents occur when workers attempt to do repairs, installation or clean-up while the conveyor system is active.
Procedures for tagging and lockout can prevent many conveyor accidents. Workers repairing conveyors, adjusting belt tracking, cleaning residues from parts or applying belt lubrication have been caught by moving parts and badly injured or killed when equipment was inadvertently activated. This can't happen if lockout procedures are consistently applied. Section 93(2) of the construction regulation (213/91) states that: "No vehicle, machine, tool or equipment shall be used while it is being repaired or serviced."
Lockout begins with determining the equipment or components to be worked on, turning off and isolating all energy sources, drawing off stored energy or potentially dangerous products, and installing tags and locks.
Equipment must be turned off and isolated even for short-duration adjustments or repairs.
Procedures must be specified for each workplace and each piece of equipment to ensure, for instance, that all energy sources (electric, hydraulic, pneumatic, etc.) involved in powering or controlling the equipment are properly isolated or locked out.
Audits conducted by supervisors can be used to ensure that procedures have been communicated and understood by the workforce and followed as required.
The use of guards on a conveyor system is not a recommendation it is a requirement. Section 109 of the construction regulation states that "Every gear, pulley, belt, chain, shaft, flywheel, saw and mechanically-operated part of a machine to which a worker has access shall be guarded or fenced so that it will not endanger a worker."
Guards on moving conveyor parts are often non-existent, inadequate, improperly positioned, or not replaced after repairs. In addition to making sure that guards are in place, operators should consider painting them in bright contrasting colours. This helps draw attention to their absence when they get lost or aren't replaced.
In addition to the general equipment requirements from the construction regulation cited above, there are specific requirements for conveyors set out in the Regulation for Mines and Mining Plants under the Occupational Health and Safety Act.
Among other points, Section 196 of the regulation requires that a conveyor have:
pull cords at accessible locations for stopping the conveyor in emergencies
a means of applying belt dressing while the conveyor is in motion
a start-up warning device when the conveyor is started automatically or by remote control or where portions of the conveyor are not visible to the operator
pulleys guarded at pinch points that are or may become accessible to workers.
Guards must also be provided beneath a conveyor that passes over workers or from which falling materials or parts may endanger workers.
For inspection and maintenance purposes, a conveyor checklist is recommended. This can be used periodically to identify components that are working properly or in need of attention. Points to check include;
· emergency stop pull cords
· start-up warning device (audible/visible)
· guards on head, tail, drive, deflection, and tension pulleys
· guards on accessible pinch points
· guards protecting workers from overhead material
· means of safely applying belt dressing and lubrication to a moving conveyor
· fire suppression system guardrails
· access equipment (walkways, ramps, stairs, platforms, etc.)
· noise control
Conditions such as misalignment at loading points, side winds, rain, snow, and build up of product can interfere with the alignment or "train" of conveyor belts.
Realigning belts is one of the highest-risk activities involving conveyors. Too often the job is done without shutting down and locking out the conveyor.
To align a conveyor belt that has shifted, workers loosen bolts on the idler framework and hammer the belt back into position.
When alignment is attempted on a moving belt, workers can get hands, tools, or clothing caught in machinery, be struck by components, or be pulled into pinch points where they may lose a limb or be crushed.
Systems such as conveyor belt conductors and self-training idlers are available to keep the belt on track. With training idlers, a manual preliminary alignment is necessary, but after that, any factors causing the belt to wander are automatically corrected.
Self-tracking systems reduce the risk of injury to operators and damage to equipment. The systems also cut maintenance requirements.
The Mining Program of the Ministry of Labour accepts the following means of compliance.
A pull cord must be positioned between a worker and unguarded idler roller pinch points on the load carrying and the return side of any conveyor belt.
Each accessible idler roller pinch point must be guarded with a suitable and effective guard.
The entire conveyor must be effectively enclosed to prevent access to the unguarded idler pinch points.
The idler roller pinch points must be elevated and beyond the reach of a person.