1. Guarding
"Australia has very good guidelines and regulations for guarding but I don't think we, as an industry, are particularly good at providing guards to comply with the guidelines," says Davis.
The problem with guards lies in operation and maintenance. Guards must comply with safety protocols - legislative and site specific. Operations need to allow easy maintenance and operation, but with comprehensive guarding this can prove difficult.
Operation and maintenance access requirement is a life of machine issue, and guards need to be designed to operate for that lifetime. "So we either produce poor guards, or good guards that prevent you from operating and maintaining the machine.
"It is a conundrum that I don't think we have quite got right yet. Good guarding should be integral with the design and not something that is added at the end to meet a standard."
The design input and manufacturing cost of effective guards is similar to that for ineffective guards. Construction controls should ensure that the guards fit with no gaps and are easy to open or remove safely for access.
2. Access control
Davis says it is important that people in general, and non-essential personnel in particular, are kept away from conveyors and that maintenance procedures ensure safe working. "If people are not next to the conveyor they can't get hurt by it.
"We generally don't fully guard conveyors, and usually do provide walkways on at least one side, so that 90% or more of the moving parts are accessible to anyone who should use the walkway when the conveyor is running.
"When a conveyor is running well and within limits, personnel access is minimised."
3. Reducing maintenance
While maintenance of the conveyor is highly important, maintenance can often increase the risk of an accident with tasks more often than not performed at heights or in enclosed spaces. "If you can keep your splicing, idler changes and pulley changes to a minimum, then you can minimise the risk."
4. Reducing spillage
Davis says it is vital that operations reduce spillage for two reasons: 1, to reduce maintenance needs and 2, because often spillage is it cleaned up when the conveyor is running increasing risk to personnel. Install a good cleaning system and then maintain it to keep it working.
5. Beyond limitations
Like the longwall and in almost every aspect of a coal mine, resources are being pushed to or beyond limits. "We started to really upgrade some of our conveyors outside what you would normally consider acceptable design limits. Some of those things are causing safety issues," says Davis.
For example, in some cases wider belts are being run too close to structures, belts are being operated at higher fill levels, components are being run faster or harder that they should be leading to increased downtime, increased maintenance and consequently decreased safety.
6. No more band aids
"Often when a problem is encountered, instead of fixing the problem properly, someone is stood 24/7 temporarily fixing it. It is not safe to have someone standing over a chute waiting to poke at build-up or hosing out or something else.
"The sorts of band aids we put on when things that don't work to me if you are going to run a plant you should fix it properly. You see these things going on for weeks, months - it becomes a fixed institution on some plants. Band aids need watching and attract people; proximity leads to potential incidents."
Davis concludes minimising risk to workers requires uptime on conveyors to be increased, meaning people have to spend less time around the conveyor.
"Keep it clean, don't overload it, do good maintenance on it, make it last longer and work properly. Our industry has improved significantly in recent years but we still have accidents"
*Davis is a materials handling consultant with Hatch and holds a Bachelor of Engineering and is a Chartered Engineer in Australia, South Africa and England. This year he is running Conveying, Stockpiling, Reclaiming & Storage courses in Perth (April 7-9) and Brisbane (November 17-19) through IIR Executive Development.