OHSA background

The Occupational Health and Safety Act (“OHSA” or "the Act") is Ontario's legislation for workplace health and safety. There are also 25 regulations under the OHSA.

The OHSA and its regulations and all of Ontario's other Acts and regulations are available on the e-Laws website.

OHSA requirements

The main purpose of the OHSA is to provide the legal framework to achieve our goal of protecting workers from health and safety hazards on the job by:

  • setting out duties for all workplace parties and rights for workers to help establish a strong internal responsibility system (IRS) in the workplace
  • establishing measures and procedures for dealing with workplace hazards
  • providing for enforcement of the law where compliance has not been achieved voluntarily

The Internal Responsibility System (IRS)

Workplace parties' compliance with their respective statutory duties is essential to the establishment of a strong IRS in the workplace.

The IRS helps support a safe and healthy workplace. The IRS means that everyone in the workplace has a role to play to keep workplaces safe and healthy.

Under the IRS, employers, supervisors and workers all have key roles to play in taking responsibility for health and safety in the workplace.

Worker responsibility

Workers in the workplace who see a health and safety problem, such as a hazard or contravention of the OHSA in the workplace, have a statutory duty to report the situation to the employer or a supervisor.

Employer responsibility

Employers and supervisors are required to address those situations and acquaint workers with any hazard in the work that they do.

The employer, typically represented by senior management, has the greatest responsibilities with respect to health and safety in the workplace.

A strong IRS is an important element of a strong health and safety culture in a workplace. A strong health and safety culture shows respect for the people in the workplace.

The respective roles and responsibilities for all workplace parties are detailed in the OHSA. This is the basis for the internal responsibility system.

Application of the OHSA

The OHSA applies to most workers, supervisors, employers and workplaces in Ontario. This includes:

  • workplace owners
  • constructors
  • suppliers of equipment or materials to workplaces

There are some limitations to the application of the OHSA. For example, it does not apply to all farming operations, such as farms operated by a self-employed person without any workers (a family farm run by a couple with no other workers). More can be found in O. Reg. 414/05: Farming Operations. There are also some prescribed limitations and conditions for teachers, found in Regulation 857: Teachers.

The OHSA does not apply to:

  • work done by the owner or occupant, or a servant of the owner or occupant, in a private residence or in the lands and appurtenances used in connection with the private residence [subsection 3(1)], and
  • workplaces under federal jurisdiction, such as:
    • post offices
    • airlines and airports
    • banks
    • grain elevators
    • telecommunication companies
    • interprovincial trucking, shipping, railway and bus companies

How federal workplaces are regulated

Workplaces under federal jurisdiction are regulated by the Canada Labour Code, which is administered by Employment and Social Development Canada.  The law that covers federal workplaces is available online on the Federal Government website. Health and safety provisions are found under Part II of the Canada Labour Code.

Types of OHSA regulations

Most of the 25 regulations under OHSA are sector, work, or hazard-specific. The other regulations provide for training, reporting and application of the OHSA.

Sector-specific regulations

Sector-specific regulations apply to a particular sector. There are sector-specific regulations for:

Hazardous work regulations

There are specific regulations for certain types of hazardous work, including:

Health hazard regulations

There are specific regulations for health hazards, including:

Other regulations

Canadian Standards Association (CSA) standards cited in OHSA regulations

The  CSA Group is a not-for-profit membership-based association serving business, industry, government and consumers in Canada and the global marketplace.

Many regulations made under Ontario’s Occupational Health and Safety Act  require compliance with standards published by the CSA Group. These standards define requirements for reducing the risk of workplace injuries.

CSA standards cited in Ontario’s occupational health and safety regulations are available online for many sectors, including industry, health care, mining, manufacturing, agriculture and construction.

You must register with "CSA Communities" to view the standards but you are under no obligation to buy anything.

How we enforce OHSA regulations

The Ministry of Labour, Training and Skills Development’s goal is for all workplaces to achieve self-compliance with OHSA and regulations through a well-functioning IRS.

Inspectors are the enforcement arm of the ministry and their role includes:

  • inspection of workplaces
  • issuing of orders where there is a contravention of OHSA or its regulations
  • investigation of critical injuries, fatalities, work refusals and health and safety complaints
  • recommendation of prosecution

The powers an inspector may use to fulfil this role are set out in OHSA sections 54 to 57. Enforcement may include issuing requirements or administrative orders against an employer or other persons, and where appropriate may result in a prosecution. Duties for employers and other persons are found in sections 23 to 32 of the OHSA for the following:  

  • constructor
  • owner
  • employer
  • architect
  • supervisor
  • engineer
  • worker
  • director or officer of a corporation
  • licensee (a holder of a logging licence under the Crown Timber Act)
  • supplier

OHSA penalties

The maximum penalties for a contravention of OHSA or its regulations are set out in OHSA section 66. A person who is convicted of an offence under the OHSA may be subject to:

  • a fine of up to $500,000 for all other persons and/or up to 12 months imprisonment
  • a fine of up to $1,500,000 for directors and officers of corporations and/or up to 12 months imprisonment
  • a fine of up to $2,000,000 for a corporation

This resource does not replace the Occupational Health and Safety Act (OHSA) and its regulations and should not be used as or considered legal advice. Health and safety inspectors will apply and enforce these laws based upon the facts they find in the workplace.