Fatal Nip-Points on Conveyors
- Mine Owners
- Mine Managers
- Mine Unions
- Mines Inspectors
Safety Circular - Reminder
In the last 10 years there have been two fatal accidents at mines where workers have been drawn into conveyors.
A conveyor cleaner suffered fatal crush injuries when he was pulled through one or more deflection drums adjacent to a belt drive whilst clearing spillage from the conveyor line. It seemed probable that he had crawled past side guards to go under the conveyor to clear spillage and had become trapped in a nip point.
The second accident happened when a beltman attempted to clean compacted fines off a rotating deflection roller using a hand held scraper. He was drawn by his arm through a 125mm gap between the roller guard and the conveyor belt, sustaining fatal injuries.
Nip guarding at the in-running nips would have prevented both of these accidents. As the power and weight of conveyors has increased the force that can be exerted by in-running nips has become greater. In addition the risks of people becoming entrapped are increased in places such as:
- Under-passes forming part of travelling routes for persons;
- Places where access is needed for maintenance purposes, particularly in front of drives, or behind loops in the conveyor belt;
- Underneath raised conveyors, where materials and tools, or other equipment are often stored;
- Underneath raised conveyors where dinting, or cleaning operations need to be performed;
- In-line bottom belt man-riding boarding platforms, where persons using the platform may make inadvertent contact with a top belt idler roller above them;
- Conveyor bridges between the bottom and top strands of a conveyor, where persons may make contact with a top belt idler roller;
- Fines conveyors, under the bottom strand of a heavy duty conveyor, where persons carrying out maintenance may make contact a bottom belt idler roller.
Managers should ensure that the hazards of in-running nips are understood and that nip points are guarded where necessary.
Further information can be found in Idler roller nip hazards on heavy duty belt conveyors
Yours sincerelyS P Wing
HM Principal District Inspector of Mines