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Blitz Results: Underground Mining Ventilation

Safe At Work Ontario
  • Issued: February 2012
  • Content last reviewed: February 2012

Ventilation hazards pose a serious concern in underground mines, many of which operate diesel equipment. The air in poorly ventilated mines can contain toxins. This can cause occupational disease and even death.

From October 1, 2011 to November 30, 2011, Ministry of Labour (MOL) inspectors conducted a blitz of hazards affecting clean air in underground mines across the province.

Inspectors ensured compliance with the Occupational Health and Safety Act (OHSA) and its regulations. They checked that:

  • ventilation systems were being properly maintained and providing an adequate supply of clean air
  • diesel equipment was being properly maintained
  • employers were regularly testing the air in underground mines to ensure concentrations of toxic substances did not exceed allowed levels

The goal was to:

  • raise awareness of air quality hazards
  • encourage employers to identify and control hazards
  • address and remedy non-compliance with the OHSA and its regulations
  • deter non-compliant employers
  • enhance health and safety partnerships
  • promote improved health and safety for workers in underground mines

Report summary

Between 2005 and 2009, 176 workers died and another 36 workers developed occupational diseases related to respiratory illnesses in the mining sector, according to claims information from the Workplace Safety and Insurance Board (WSIB).

In October and November 2011, ministry inspectors conducted 61 visits to 36 underground mines and issued 207 orders under the OHSA, including 22 stop work orders to underground mines.

The three most commonly issued orders involved violations of the employer's duty to:

  • take every reasonable precaution to protect a worker
  • prepare a plan to comply with an inspector's order
  • erect signs and barricades to isolate areas in a mine that are under repair or are otherwise hazardous

Full report

Workplace inspection blitzes

Inspection blitzes are part of the province's Safe At Work Ontario compliance strategy. They are announced to the sector by the ministry in advance although individual workplaces are not identified in advance. Results are posted on the ministry's website. The blitzes raise awareness of known workplace hazards and promote compliance with the OHSA and its safety regulations.

Inspectors' findings may impact the frequency and level of future inspections of individual workplaces. Inspectors refer employers to health and safety associations for compliance assistance and training.

Blitz focus

Mining inspectors focused on the following key priorities:

  • Ventilation Systems: Inspectors checked that ventilation systems were providing an adequate clean air supply in underground mines. This included checking auxiliary ventilation systems which are used to bolster the air quality in areas where diesel equipment is operated.
  • Diesel Equipment: Inspectors checked that diesel equipment was being properly maintained. This equipment is used for underground transportation of workers and materials and blasting of rock.
  • Workplace Air Sampling: Inspectors checked that employers were regularly testing the air in underground mines to ensure concentrations of toxic substances did not exceed levels set in the Regulations for Mines and Mining Plants.

Inspection activity

Inspectors conducted 61 visits to 36 underground mines and issued 207 orders for violations of the OHSA and Regulations for Mines and Mining Plants involving ventilation in underground mines.

Of the 207 orders issued, 22 orders were stop work orders.

A summary of the ventilation blitz activity is shown in the following table.

Table 1: Orders for violations of the OHSA and Regulations for Mines and Mining Plants involving ventilation in underground mines.
  Mining sector ventilation blitz inspections
Oct. 1 to Nov. 30, 2011
Number of Workplaces visited 36
Total visits[ 1 ] 61
Orders (all types) 207
Stop work orders Underground Mines 22
Orders per visit 3.4
Stop work orders per visit (Underground minies) 0.36

Order analysis

Orders were issued for various violations of the Occupational Health and Safety Act (OHSA) and Regulation for Mines and Mining Plants.

A breakdown by order type is shown in the table below.

Table 2: Orders issued under the Occupational Health and Safety Act (OHSA),
and Regulations for Mines and Mining Plants
Reason for order Number of orders Percentage
of total orders issued
Employer duty to take every reasonable precaution to protect a worker [OHSA S. 25(2)(h)] 24 11.5%
Employer duty to prepare a plan to comply with an inspector's order [OHSA S. 57(4)] 11 5%
Employer duty to erect signs or barricades to isolate hazardous areas in a mine [Mining Reg. S. 68(a)&(b)] 11 5%
Employer duty to fill out a notice when diesel-powered equipment is first used [Mining Reg. S. 182(1)] 9 4.3%
Employer duty to maintain a chart outlining procedures for ventilation when diesel is present [Mining Reg. S. 183] 9 4.3%
Worker duty to comply with OHSA and its regulations  [OHSA S. 28] 2 1.0%

Conclusion

The underground mining ventilation blitz was an important enforcement initiative that focused on serious workplace hazards in underground mines.

The blitz identified violations of the OHSA and mining regulation and created a greater level of awareness of ventilation hazards in underground mines.

Mining inspectors were accompanied by members of the ministry's Specialized Professional Services (SPS) Unit (engineers and hygienists) during the blitz. This enabled the ministry to probe more deeply into the state of mine ventilation in underground workplaces.

Next steps

The ministry will continue to focus on conditions in underground mines to fulfil its mission of advancing healthy, safe and productive workplaces in Ontario.

Inspectors will check that proper mechanical ventilation systems are in place, being maintained and are providing the required clean air.

Staff from the ministry's Specialized Professional Services will continue to provide support to mining inspectors in mine ventilation.

Recent mining regulation amendments include new requirements to better protect underground mine workers from exposure to diesel particulate matter and other toxins.

The new limits for total carbon exposure will require employers to use a different method of diesel exhaust testing on equipment. Employers will also be required to consult with the workplace's Joint Health and Safety Committee (JHSC) or health and safety representative on the testing.

Future enforcement will focus on these new requirements, and the ministry will continue to raise awareness of ventilation hazards in underground workplaces.

A key to workplace health and safety in Ontario is the internal responsibility system (IRS). Employers, supervisors and workers all have key roles to play in taking responsibility for health and safety in the workplace, leading to the elimination of workplace injuries and deaths. Safety partners also play a role – health and safety associations provide compliance advice and education, and the government enforces health and safety legislation.

Workplace parties are encouraged to work together to identify and control potential hazards related to improper ventilation and diesel equipment requirements in underground mines.

Compliance help for employers

For more information on identifying, preventing and controlling workplace hazards, please contact our safety partners.

[ 1 ]Refers to the total number of individual visits MOL inspectors made to all workplaces during this blitz.