Occupational Health and Safety Act

The Occupational Health and Safety Act (OHSA) sets out, in very general terms, the duties of employers and others to protect workers from health and safety hazards on the job. These duties include, but are not limited to:

  • taking all reasonable precautions to protect the health and safety of workers [clause 25(2)(h)],
  • ensuring that equipment, materials and protective equipment are maintained in good condition [clause 25(1)(b)],
  • providing information, instruction and supervision to protect worker health and safety [clause 25(2)(a)], and
  • acquainting a worker or a person in authority over a worker with any hazard in the work and in the handling, storage, use, disposal and transport of any article, device, equipment or a biological, chemical or physical agent [clause 25(2)(d)].

In addition, section 30 of the OHSA deals with the presence of designated substances on construction projects. Since silica is a designated substance (O. Reg. 490/09), compliance with the OHSA and its regulations requires action to be taken where there is a silica hazard on a construction project.

Section 30 of the OHSA requires the owner of a project to determine if silica is present on a project and, if it is, to so inform all potential contractors as part of the bidding process. In a similar way, contractors who receive this information are to pass it onto other contractors and subcontractors who are bidding for work on the project. If the owner or any contractor fails to comply with this requirement, they will be liable for any loss or damages that result from a contractor subsequently discovering that silica is present.

Workplace Hazardous Materials Information System (WHMIS) Regulation (R.R.O. 1990, Reg. 860)

The WHMIS Regulation applies to all workplaces covered by the OHSA. Any employer or constructor who uses WHMIS controlled products is required to comply with the WHMIS Regulation regarding the requirements for labels, material safety data sheets, and worker education and training.

The Ministry of Labour is responsible for the administration and enforcement of both federal and provincial WHMIS legislation.

Regulation for Construction Projects (O. Reg. 213/91)

The Regulation for Construction Projects, O. Reg. 213/91, applies to all construction projects. Although silica is not mentioned specifically, the following sections of the regulation would apply to situations where there is the potential for workers to be exposed to silica:

Section 14

(5) A competent person shall perform tests and observations necessary for the detection of hazardous conditions on a project.

Section 21

(1) A worker shall wear such protective clothing and use such personal protective equipment or devices as are necessary to protect the worker against the hazards to which the worker may be exposed.

(2) A worker's employer shall require the worker to comply with subsection (1).

(3) A worker required to wear personal protective clothing or use personal protective equipment or devices shall be adequately instructed and trained in the care and use of the clothing, equipment or device before wearing or using it.

Section 30

Workers who handle or use.substances likely to endanger their health shall be provided with washing facilities with clean water, soap and individual towels.

Section 46

(1) A project shall be adequately ventilated by natural or mechanical means,

(a) if a worker may be injured by inhaling a noxious.dust or fume;

(2) If it is not practicable to provide natural or mechanical ventilation in the circumstances described in clause (1)(a), respiratory protective equipment suitable for the hazard shall be provided and be used by the workers.

Section 59

If the dissemination of dust is a hazard to a worker, the dust shall be adequately controlled or each worker who may be exposed to the hazard shall be provided with adequate personal protective equipment.

Regulation for Designated Substances (O. Reg. 490/09)

The Ministry’s Designated Substances Regulation (O. Reg. 490/09) specifies occupational exposure limits (OELs) for silica and requires an assessment and a control program to ensure compliance with these OELs. The OEL for respirable crystalline silica is 0.05 milligrams per cubic meter (mg/m3) of air by volume as an 8-hour daily or 40 hour weekly time-weighted average limit for cristobalite. In the case of quartz and tripoli, the OEL is 0.10 milligrams per cubic meter (mg/m3) of air by volume.

Although O. Reg. 490/09 and the OEL for silica do not apply to an employer on a construction project or to their workers at the project, employers still have a responsibility to protect the health of their workers and to comply with the OHSA and other applicable regulations. Section 25(2)(h)of the OHSA requires that employers take “every precaution reasonable in the circumstances for the protection of a worker.”