Ontario’s Occupational Health and Safety Act (“OHSA”) has been in force since 1979 and it remains the primary provincial law governing occupational health and safety in the workplace. The foundational concept of the OHSA is the Internal Responsibility System (“IRS”), which is based on the principle that everyone in the workplace, including workers and employers, are responsible for safety and for the safety of those around them. The term IRS is widely used in the field of health and safety however, it is not directly referenced in any health and safety legislation across Canada. The Ontario Ministry of Labour’s (“MOL”) guide to the OHSA makes it clear that the government expects employers and workers to cooperate to control occupational health and safety hazards. With that said, the OHSA also sets out the rights and legal duties of all workplace parties including; employers, supervisors, and workers to ensure that health and safety hazards in the workplace are controlled.

The evolution of the IRS began in 1974 when Uranium miners in Elliot Lake became concerned after abnormal rates of lung cancer and silicosis among miners caused them to go on strike. The Ontario government then appointed a Royal Commission, chaired by Dr. James Ham, to investigate the health and safety of miners. This commission became to be known as the Ham Commission.

In 1975, the Ham Commission Report recommended joint health and safety committees. For every workplace in 1976, Bill 139 established the Employee’s Health and Safety Act, which gave the power to the Minister to order joint committees. In 1978, Bill 70 established the OHSA, which made it mandatory for joint health and safety committees to be established in many workplaces. In 1987, Bill 79 added Workplace Hazardous Materials Information System (WHMIS) to the OHSA. In 1990, Bill 208 amended the OHSA, broadening the requirement for joint health and safety committees and established the requirement for certified members and the right to stop work.

All told, more than 100 recommendations were included in the Ham Commission Report. Dr. Ham further developed the idea of an internal responsibility system, which would require the government, employers, supervisors and workers to cooperate in order to improve health and safety.

Further amendments to the OHSA established new procedures as well as new worker rights including, the right to know, the right to refuse and the right to participate. These amendments also established additional rights for the joint health and safety committees giving them the right to participate in making health and safety recommendations, and in controlling workplace hazards.

Recent milestones for the OHSA include proposed amendments to address workplace violence and harassment. On April 20, 2009, the Ontario government introduced Bill 168, the Occupational Health and Safety Amendment Act (Violence and Harassment in the Workplace), 2009. If passed, Bill 168 will amend the OHSA to impose new obligations on employers with respect to workplace violence and harassment. For more information on this, please visit www.gowlings.com/ohslaw for scheduled dates on our seminar titled, “Preparing for the “New” Workplace Violence Legislation Bill 168 (An Act to amend the OHSA)”.

In summary, the OHSA establishes procedures for dealing with workplace hazards, sets out the rights and legal duties of workplace parties and it also provides for enforcement of the law by the MOL where compliance has not been achieved voluntarily.