Task – Feed the materials
Entanglement with turning screw
- Trapped hands, feet or other limbs in a nip
- Crush injuries
- DESIGN should ensure the hazard of the screw is isolated.
- FIX guarding.
- RESTRICT guard openings to prevent hands reaching the rotating part of the conveyor (auger).
- FIT inlet ends with hoppers.
- NEVER WEAR jewellery or loose clothing, and TIE BACK long hair.
The turning screw can trap limbs. It can also trap loose clothing, long hair, and dangling jewellery. Traps at screws are most commonly at the feed or delivery end. However if the screw turns while the guards are off, traps are exposed along its whole length.
Contact or impact from moving parts
- GUARD prime mover and moving mechanical transmission to isolate moving parts.
Figure 3: Hopper with bars across opening to isolate the screw
Figure 4: Hopper guards with restricted movement
Wheel spacing must ensure stability if product is in the top half only of the raised auger, including when the ground is uneven.
Task – Sample collection
Troughs – reaching or falling
- Impact injury from fall
- Amputation or crushing from being caught in a nip
- FIT a bend to the delivery end of the trough, with dimensions to prevent reach.
- FIT high walls to prevent reaching or falling into the trough.
- FIT secondary safeguarding for open troughs, e.g. railing or fencing.
- DESIGN collection points to ensure that hazards remain isolated.
- LOCK-OUT power before starting work within the trough.
Delivery ends can be safe by position, ie. too high for reach into the hazards, or the delivery end can be designed to isolate the screw.
Figure 5: Example of sampling device
Other (non-mechanical) hazards
- Electric shock from faulty wiring
- If the prime mover is electric, regularly TEST the portable auger to maintain electrical safety.
Slips trips and falls
- KEEP up-to-date housekeeping procedures.
- KEEP the area around conveyors clear of slip and trip hazards.
Task – Maintenance, cleaning & repairs
Entrapment from unexpected movement
- Crush injuries
- LOCK-OUT all power supplies before maintenance, cleaning or repairs.
- An auger or screw conveyor that does not have a screen or cover, or is not secured by bolts or clamps, MUST have an INTERLOCKED COVER that cuts the power when raised and does not re-start until the cover is replaced and the starter activated.
Cleaning and maintenance will almost always require removal of covers or guards. The screw MUST not start until people are clear and guards replaced.