New Ministry of Labour mining guidelines

Wednesday, July 15, 2015

Government issues guides for surface, underground mines

Hazard alert: Wheel rim assembly failures - please print, post and encourage discussion in the workplace

Underground miners check ventilation readingsThis summer, the Ontario Ministry of Labour issued three new mining guidelines on (1) safe and reliable braking systems on vehicles, (2) requirements and hazards involving tire and wheel assemblies, and (3) the sampling of diesel particulate matter.

The purpose of the guidelines is to assist employers, workers and other workplace parties in understanding the requirements in Regulation 854 (Mines and Mining Plants) under the Occupational Health and Safety Act (OHSA). Each guideline includes a description of potential hazards, acceptable practices, legal requirements, and resources available for mining health and safety.

1. Guidelines for mine vehicle brakes

A failure in the service brake system of a motor vehicle operating on a ramp in an underground or surface mine can cause a runaway and serious injury if there is no back-up brake system. 

Potential brake failures could result in runaways of motor vehicles if the brake systems are not tested during operation. The guidelines include industry practices and motor vehicle brake system test requirements. Learn more

2. Guidelines for wheel rims and tire assemblies

Workers are injured or killed every year while handling tires and wheel assemblies at Ontario workplaces, particularly when inflating or repairing tires, or if components are overheated or improperly repaired. 

Hazard examples:

  • During tire inflation, sudden and violent spring of the tire lock rings, rims or flanges resulting in flying objects that can strike nearby workers causing serious injuries or death
  • During tire inflation, “zipper rupture” (failure of a tire sidewall in steel cord radial tires) causes a blast of air that can hurl tire and wheel assembly pieces at workers, causing injury
  • Flammable gases in products used for seating of a tire bead or repairing punctures and leaks can cause a tire explosion
  • If tires, rims or wheels become heated due to a: vehicle being near or touching a high voltage power line; fire from overheated brakes; torch heating a wheel; stud being cut off a wheel or; wheel being welded, the tire can explode due to “pyrolysis” or chemical decomposition  Learn more

3. Guidelines for sampling diesel particulate matter

As more information becomes available, it’s evident that diesel particulate matter (DPM) continues to be a significant health risk in mines. The most accurate measurement to reflect the amount of DPM produced by a diesel engine is to measure the elemental carbon portion of the total carbon produced.

The lower limit of 0.4 mg/m³ for total carbon set out in clause 183.1(5)(a) or based on elemental carbon set out in clause 183.1(5)(b) will require a more accurate analytical method than the current RCD method. The accepted method, in North America, is the NIOSH 5040 which accurately measures both the elemental and organic carbon portions of the total carbon found in mines.

The Respirable Combustible Dust (RCD) method is non-selective, and interferences such as oil mists, cigarette smoke and mineral dust could be measured indiscriminately as total carbon and contribute to what appears to be diesel exposure. In addition, research has shown that the RCD method is not recommended for compliance measurements in jurisdictions where the exposure limit is less than 0.6 mg/m³. Learn more


Summer safety blitz targets mine traffic – Ministry of Labour

Blitz results: Water Management in Underground Mines 2015 – Ministry of Labour

Ontario issues 172 orders during safety blitz at underground mines – Canadian Occupational Safety (COS) magazine

Ontario mining health and safety information and services 

Workshop: Practical Auxiliary Mine Ventilation – September 2, 2015 Timmins and Matheson

Manual: Auxiliary Mine Ventilation

Presentation: Tire and Wheel Safety Awareness 

Hazard alert: Wheel rim assembly failures

Safety blitz targets water in underground mines