Workplace Health and Safety Basics for Ontario Employers: The OHSA Explained

Every Ontario employer — from a two-person trades shop to a mid-sized manufacturer — has legal obligations under the Occupational Health and Safety Act (OHSA). Violations can result in Ministry of Labour, Immigration, Training and Skills Development (MLITSD) orders, stop-work orders, and significant fines. More importantly, failure to take health and safety seriously can injure the people who work for you. This guide covers the fundamentals every Ontario business owner should know.

The Core Duty: Take Every Precaution Reasonable in the Circumstances

The OHSA's foundational obligation is that every employer shall take every precaution reasonable in the circumstances for the protection of a worker. This is a broad, open-ended duty. It means you cannot simply comply with specific rules and consider yourself done — you must think proactively about the hazards in your workplace and address them.

Who Has Duties Under the OHSA?

The OHSA assigns duties to multiple parties in a workplace. Understanding who is responsible for what prevents the gaps that cause accidents:

• Employers — the broadest obligations; responsible for the physical workplace, equipment, training, supervision, and enforcement of safe work practices
• Supervisors — must ensure workers use required protective equipment and follow safe work procedures; must advise workers of hazards
• Workers — must follow safe work practices, use required equipment, and report hazards and injuries
• Owners — the owner of the building or premises has independent duties regarding the physical structure
• Constructors and contractors — construction sites have additional layered obligations

An employer cannot delegate away its OHSA obligations by pointing to a supervisor's failure.

What Every Ontario Employer Must Do

Post the Act and Your Health and Safety Policy

The OHSA requires employers to post a copy of the Act and your workplace health and safety policy in a prominent place in the workplace. Employees must be able to read them.

Employers with six or more regularly employed workers must have a written occupational health and safety policy and a workplace violence and workplace harassment policy (under the Workplace Violence and Harassment provisions of the OHSA). These policies must be reviewed annually.

Establish a Joint Health and Safety Committee or Health and Safety Representative

• 20 or more workers regularly employed: you must establish a Joint Health and Safety Committee (JHSC) with at least two members, co-chaired by a worker representative and a management representative. JHSC members have rights to inspect the workplace, investigate work refusals, and make recommendations.
• 6 to 19 workers regularly employed: you must have a health and safety representative selected by workers.
• Fewer than 6 workers: no formal committee or representative required, but your other OHSA duties still apply.

Conduct Workplace Inspections

The workplace must be regularly inspected for hazards. JHSC members or the health and safety representative conduct these inspections; findings must be reported in writing to the employer.

Report Injuries and Critical Injuries

When a critical injury occurs (an injury of a prescribed type that is life-threatening or causes serious consequences), the employer must notify the MLITSD immediately (typically by phone) and follow up in writing within 48 hours (as of writing — verify current timeframes). The scene of a critical injury cannot be disturbed until an inspector arrives or authorizes otherwise, except to save a life.

Injuries that result in lost time or medical attention beyond first aid must be recorded in an accident log and reported to WSIB (Workplace Safety and Insurance Board) separately.

Train Workers

Workers must be trained on the hazards specific to their work. For certain high-risk activities and industries (construction, mining, confined spaces, working at heights), specific OHSA-mandated training programs exist. General safety orientation for new workers is required.

The Right to Refuse Unsafe Work

A worker has the right under the OHSA to refuse to perform work they believe is likely to endanger themselves or another worker. The refusal process has two stages:

Stage 1: The worker tells the supervisor or employer of the refusal. The supervisor and worker investigate. If the issue is resolved, work resumes.

Stage 2: If not resolved, the worker continues to refuse. A JHSC member or health and safety representative joins the investigation. If still unresolved, the MLITSD is notified and an inspector investigates.

An employer cannot discipline, threaten, intimidate, or penalize a worker for exercising their right to refuse. Doing so is a violation of the OHSA and can result in reinstatement orders and damages.

Ministry Inspections and Orders

MLITSD inspectors can enter any workplace without advance notice. An inspector can:

• Observe work, equipment, and materials
• Speak with any person in the workplace
• Take photographs and samples
• Issue orders to comply — requiring you to fix a hazard by a deadline
• Issue stop-work orders — halting operations immediately
• Issue orders to suspend use of specific equipment
• Commence prosecution for serious violations

Orders are legal documents. Failing to comply by the deadline is itself a separate violation. If you receive an order, get legal advice and address it promptly — do not ignore it hoping it goes away.

Penalties for OHSA Violations

Penalties for OHSA violations can be significant (as of writing — verify current maximums). Individual directors and officers of corporations can be personally liable for OHSA violations. Courts have imposed jail sentences in serious cases involving worker deaths. The reputational and human cost of a serious workplace injury or death is incalculable.

Frequently asked questions