THE INTERNAL RESPONSIBILITY SYSTEM — HOW ONTARIO SAFETY LAW ACTUALLY WORKS

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If you have ever taken a health and safety awareness course in Ontario, you have heard the term "Internal Responsibility System." It gets mentioned in every orientation, every toolbox talk outline, and every OHSA training module. But ask most workers what it actually means in practice, and you will get vague answers about "everyone being responsible for safety."

That vagueness is a problem, because the Internal Responsibility System (IRS) is not a feel-good slogan. It is the foundational principle of Ontario's entire occupational health and safety framework. Understanding how it works — and what it demands from every person on a construction site — is essential to staying safe and staying legal.

What Is the Internal Responsibility System?

The Internal Responsibility System is the principle that every person in a workplace — from the company owner to the newest apprentice — has a direct responsibility for health and safety as an essential part of their job. Safety is not delegated to a safety department or a single safety officer. It is built into the role of every individual at every level.

The IRS was first articulated in the 1976 Ham Commission report, which led to the creation of Ontario's Occupational Health and Safety Act (OHSA) in 1979. The idea was revolutionary at the time: instead of relying solely on government inspectors to enforce safety from the outside, the system places the primary responsibility on the people inside the workplace — because they are the ones who know the hazards, see the risks, and can act on them immediately.

The OHSA does not use the phrase "Internal Responsibility System" explicitly, but the entire structure of the Act is built around it. The duties assigned to employers, constructors, supervisors, and workers in Sections 23 through 28 of the OHSA create the legal framework that makes the IRS enforceable.

Employer Duties Under the IRS

Employers carry the greatest share of responsibility because they have the greatest control over the workplace. Under Section 25 of the OHSA, employer duties include:

• Providing information, instruction, and supervision — workers must be told about hazards, trained on safe procedures, and supervised to ensure they follow them
• Taking every precaution reasonable in the circumstances — this is the general duty clause, and it is intentionally broad. If a hazard exists and a reasonable precaution could address it, the employer is expected to act — whether or not a specific regulation covers it.
• Ensuring equipment, materials, and PPE are provided and maintained — from hard hats to fall protection systems, the employer must supply what workers need and ensure it is in safe working condition
• Preparing and maintaining a health and safety policy — workplaces with 6 or more workers must have a written policy, reviewed annually
• Establishing a joint health and safety committee or health and safety representative — depending on workplace size
• Not requiring or permitting work in contravention of the Act — an employer cannot direct a worker to do something that violates the OHSA or its regulations, and cannot allow such work to continue

Supervisor Duties Under the IRS

Supervisors are the critical link between management policy and on-the-ground practice. Under Section 27 of the OHSA, a supervisor must:

• Ensure workers comply with the Act and its regulations — if a worker removes a guardrail or takes off their harness, the supervisor is legally obligated to intervene
• Ensure workers use or wear the required protective equipment — and that equipment is used properly, not just carried
• Advise workers of actual or potential hazards — the supervisor must communicate hazards that they know about or ought reasonably to know about
• Take every precaution reasonable for the protection of a worker — the same general duty clause that applies to employers also applies to supervisors individually

This means a supervisor who sees a hazard and does nothing can be held personally liable under the OHSA. "I didn't know" is not a defence if the hazard was one they should reasonably have been aware of. Supervisors have been personally fined and, in extreme cases, jailed for failing to meet their duties.

Worker Duties Under the IRS

Workers are not passive recipients of safety. Under Section 28 of the OHSA, every worker has specific legal obligations:

• Work in compliance with the Act and its regulations — follow the rules, use the equipment, and perform work the way you were trained
• Use or wear the protective equipment required by the employer — if your employer requires a harness, you must wear it. If safety glasses are mandatory on site, you must have them on.
• Report hazards to the supervisor — if you see a missing guardrail, a damaged ladder, or an unsafe condition, you must report it. You cannot simply walk past it.
• Report any contravention of the Act or regulations — if you witness a violation, you have a duty to report it to your supervisor or employer
• Not remove or disable any protective device — guards on equipment, guardrails, barriers, and other safety devices must stay in place
• Not use or operate equipment in a way that may endanger yourself or others
• Not engage in any horseplay, contest, or unnecessary running — this is directly stated in the Act

How the IRS Works on a Construction Site

Consider a concrete forming crew on a high-rise project. The IRS creates a chain of responsibility that looks like this in practice:

The constructor (the general contractor with overall responsibility for the project) ensures that fall protection systems are specified in the project safety plan, that all subcontractors are informed of the requirements, and that compliance is monitored across all trades.

The employer (the forming subcontractor) provides approved harnesses, lanyards, and anchor systems to its workers. It ensures that every worker has completed Working at Heights training and holds a valid certificate. It develops task-specific safe work procedures for forming at height.

The supervisor (the forming foreman) conducts a pre-task hazard assessment each morning, ensures guardrails are in place before workers access the deck, verifies that every worker is tied off when required, and intervenes immediately if anyone is working without fall protection.

The workers (the carpenters and labourers) inspect their harnesses before each use, connect to approved anchor points, report any damaged equipment to the foreman, and alert the supervisor if they see a co-worker working without protection or if a guardrail has been removed.

If any link in that chain fails, the system breaks down. A harness sitting in a worker's truck does not prevent a fall. A supervisor who looks the other way when workers are not tied off has failed their legal duty. An employer who provides equipment but no training has not met the standard.

The Role of the Joint Health and Safety Committee

The Joint Health and Safety Committee (JHSC) is the formal mechanism through which workers and management collaborate on health and safety within the IRS. On construction projects with 20 or more workers regularly employed, a JHSC is required. For projects with 5 to 19 workers, a health and safety representative is required.

The JHSC does not replace individual responsibilities — it supports the IRS by:

• Conducting workplace inspections — committee members walk the site regularly to identify hazards
• Receiving and addressing worker concerns — providing a formal channel for workers to raise safety issues
• Making written recommendations to the employer — the employer must respond within 21 days
• Participating in investigations — after critical injuries, fatalities, or work refusals
• Reviewing health and safety programs and policies

The JHSC must have both worker and management members, with at least half being worker representatives selected by the workers (not appointed by management). This ensures that workers have a genuine voice in safety decisions.

When the IRS Fails — Enforcement

The IRS is designed to be self-correcting. When it works properly, hazards are identified and resolved internally without government intervention. But when internal mechanisms fail, the Ministry of Labour, Immigration, Training and Skills Development (MLITSD) steps in as the external enforcement backstop.

Ministry inspectors can:

• Enter any workplace at any time without a warrant
• Issue compliance orders requiring specific corrective actions
• Issue stop-work orders halting all or part of a project immediately
• Lay charges under the OHSA leading to prosecution and fines

The enforcement system exists precisely because the IRS sometimes fails. But inspectors cannot be on every site every day — Ontario has thousands of active construction projects and a finite number of inspectors. The system depends on the people inside the workplace doing their part.

Making the IRS Real

The IRS only works when every person on site takes their responsibilities seriously — not because an inspector might show up, but because a failure in the system can result in someone going home in an ambulance instead of in their truck. It is not about paperwork or compliance checklists. It is about a shared commitment that no one gets hurt today.

If you are a worker, report hazards. If you are a supervisor, act on them. If you are an employer, provide the resources, training, and culture that make safety possible. That is the Internal Responsibility System — not as a concept, but as a daily practice.