A worker at the primary crusher was carrying out clean-up and housekeeping duties when personal monitoring measured respirable silica levels at about six times the exposure standard.
While the worker was wearing a disposable respirator, it wasn’t the most effective choice for the conditions. A disposable respirator can only offer a protection factor of up to 10 times the exposure standard—and that’s only if its wearer is cleanly shaven and wears it correctly for the entire exposure period.
Generally, industry compliance with respirable silica dust standards is excellent, but WorkSafe Mines Safety knows that workers in primary crusher areas, exploration drilling activities and sample preparation in laboratories face the greatest risks. The health management plan of this reportable incident’s site specified it should include high-risk personnel, but the worker wasn’t a member of a health monitoring program.
Key takeaways
- Identify hazards—Respirable silica dust is a reasonably foreseeable hazard that could give rise to risks to health and safety [r. 34].
- Use control measures—Substituting (wholly or partly) or implementing engineering controls to address the hazard of respirable silica dust is the most effective measure in the hierarchy [r. 36(3)]. However, if it’s impossible to eliminate a hazard, personal protective equipment may be necessary [r. 36(5)]. A disposable respirator isn’t always the best choice—a powered air-purifying respirator offers better protection and greater reliability.
- Supply health monitoring—A mine operator must provide health monitoring if respirable silica dust presents a risk of an adverse effect on a worker’s well-being, and valid detection techniques exist [r. 675F].
