Mental Health Under the OHS Act: What Canadian Employers Are Legally Required to Do

Mental health is not separate from occupational health and safety. In Canada, provincial and territorial OHS laws require employers to protect workers from harm — physical and psychological. Ignoring workplace mental health is not a policy gap. It is a legal risk.

What does the OHS Act say about mental health? What are your obligations as an employer? This post breaks it down.

Mental Health Is an OHS Issue

Most Canadian OHS legislation covers “workplace hazards” broadly — and courts have confirmed psychological hazards fall within scope. Under OHS law, employers have a general duty to take all reasonable precautions to protect workers from foreseeable harm — including harm from excessive stress, harassment, and psychosocial risk factors.

The Mental Health Commission of Canada has been clear: psychological health and safety is a workplace responsibility. Organizations across Canada are being held to this standard in courts and workers’ compensation tribunals alike.

Psychological injury claims are rising. WSIB Ontario has seen a measurable increase in accepted mental stress claims over the past decade. Other provinces show the same trend.

The CSA Z1003 Standard: Canada’s Benchmark

Canada’s national standard for psychological health and safety in the workplace — CSA Z1003 — was first published in 2013. It outlines a systems-based approach to identifying, assessing, and controlling psychosocial hazards at work.

While adoption of the standard is voluntary, courts and tribunals increasingly treat it as the benchmark for what a reasonable employer should do. Employers who ignore it take on greater exposure in WSIB claims, human rights complaints, and wrongful dismissal cases.

The 13 psychosocial factors addressed in CSA Z1003 include:

• Organizational culture and values
• Psychological demands and workload
• Clear leadership and expectations
• Civility and respect among colleagues
• Protection from workplace violence
• Work-life balance and schedule management
• Psychological competence of leaders

Training your leaders and HR teams on these factors is a practical step toward compliance — and toward preventing incidents before they become formal claims.

Your Legal Duties Under OHS Legislation

Here is what OHS legislation across Canadian provinces requires of employers when it comes to psychological safety in the workplace.

1. Identify hazards

You must assess workplace conditions for psychological risks — not physical risks alone. This includes shift work, role ambiguity, social isolation, high-demand environments, and exposure to traumatic events. Assessments should be documented and repeated when conditions change.

2. Control hazards

Once identified, you must take reasonable steps to eliminate or minimize the risks. This includes policy changes, workload reviews, and targeted leadership training. Documenting your actions is critical — it is your evidence of due diligence.

3. Train workers

Workers must be trained to recognize hazards and know your reporting procedures. Evidence-based mental health training — like Psychological Health and Safety (PHS) training — fulfills this obligation and gives your HR team the tools to respond effectively to mental health concerns before they escalate.

4. Investigate incidents

Mental health-related incidents — harassment complaints, psychological injury claims, and workplace violence reports — require formal investigation under most OHS regimes. A documented, consistent process protects both workers and the organization.

5. Maintain a harassment and violence prevention policy

Under federal Bill C-65 and equivalent provincial laws, employers must maintain a written policy addressing workplace harassment and violence. Both are recognized psychological hazards. Without a current, communicated policy, your organization is exposed — legally and reputationally.

The Cost of Non-Compliance

Employers who fail to address psychological hazards face real consequences:

• OHS orders and fines from provincial inspectors
• WSIB or workers’ compensation claims with employer experience rating surcharges
• Human rights tribunal applications
• Constructive dismissal suits tied to toxic or high-demand workplace conditions

Mental health claims now account for a growing share of all workers’ compensation disputes in Canada. Courts are not sympathetic to employers who treat psychological safety as secondary to physical safety.

Is your OHS program built to withstand a tribunal review?

What Proactive Employers Are Doing

Organizations ahead of the curve are not waiting for claims to force change. They:

• Conduct annual workplace psychological health audits
• Train people leaders using evidence-based programs like The Working Mind (TWM) — built specifically for Canadian managers and employees
• Build return-to-work plans designed for mental health-related absences, not physical injury alone
• Create psychological safety plans aligned with CSA Z1003
• Track leading indicators — absenteeism rates, short-term disability claims, and turnover — not reactive incident counts

The Canadian Centre for Occupational Health and Safety (CCOHS) offers free guidance on building OHS programs with a mental health component — a practical starting point for organizations at any stage of their compliance journey.

Where to Start

If your organization has not reviewed its OHS program for psychological hazards, start with a gap analysis:

1. Review your existing OHS policy — does it mention psychological safety or psychosocial hazards?
2. Conduct a workplace assessment using a validated tool (Guarding Minds @ Work is a free, research-based option)
3. Train your leaders and HR team on recognizing and responding to mental health concerns
4. Document every step — this creates the paper trail protecting you in future claims
5. Review your harassment and violence prevention policy for gaps, and update it annually

Compliance is a floor, not a ceiling. Employers who treat mental health as a legal checkbox do the minimum. Those who treat it as a strategic priority see measurable improvements in retention, engagement, and reduced claims costs.

Your OHS obligations include mental health. The question is whether your organization is meeting them — and whether you have the documentation to prove it.