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Supervisor Due Diligence Basics

17 min · February 15, 2026

Playing from: Supervisor Conversations · 2 episodes in series

Show Notes

Due diligence is a legal standard in Ontario's Occupational Health and Safety Act — and the most common defence in OHSA prosecutions. But what does it actually mean on the ground? This episode breaks down the concept for supervisors: what they're expected to know, what they're expected to do, and how to document their actions so the record reflects the care they took. The key insight: due diligence isn't a paperwork exercise — it's the habit of taking reasonable steps every day.

Key Learning Points

  • Due diligence means taking every reasonable precaution in the circumstances — supervisors are personally accountable for this standard
  • Ontario courts assess due diligence based on what a reasonably competent supervisor would have known and done under the same conditions
  • Documentation proves due diligence — it does not create it; the consistent, reasonable action comes first
  • Supervisors must stop work when a hazard cannot be immediately controlled — the obligation exists independently of a worker's right to refuse
  • Pre-shift hazard assessments, toolbox talks, and competency verification are the practical building blocks of demonstrable due diligence
17 min
February 15, 2026

Transcript

[INTRO]

Host: Welcome to WorkSafe Sounds. Today's topic is one that every supervisor needs to understand early in their role — what due diligence actually means and what it looks like in practice.

Guest: Thanks for having me. Due diligence is one of those legal terms that gets used frequently but rarely explained well. Let's fix that.

Host: Let's start with the basic definition. What is due diligence under Ontario's OHSA?

Guest: Under the Act, due diligence is the legal standard a supervisor — or an employer — must meet to avoid conviction for a safety offence. If you're charged with an OHSA violation, you can raise a due diligence defence under Section 66. To succeed, you have to prove you took every reasonable precaution in the circumstances.

Host: Every reasonable precaution. What does that look like?

Guest: Courts apply an objective standard — they ask what a reasonably competent person in your role would have known and done. If you were aware of a hazard and did nothing, that's a serious problem. If the hazard wasn't foreseeable, the standard adjusts. The courts look at the full picture: your knowledge, your authority, the conditions that day.

Host: A lot of supervisors I work with think due diligence means keeping records.

Guest: That's the most common misconception. Documentation doesn't create due diligence — it proves it. The actual due diligence is the consistent, reasonable action you take: pre-shift hazard assessments, ensuring workers are trained and competent for their specific task, correcting unsafe conditions when you see them, stopping work when a hazard can't be controlled. The paperwork records what you did. It doesn't substitute for doing it.

Host: Where does the right to stop unsafe work fit in?

Guest: Section 43 of the OHSA gives workers the right to refuse unsafe work. But supervisors have an obligation under Section 27 — they must take every reasonable precaution to protect workers. That includes stopping work when a hazard cannot be immediately controlled. As a supervisor, you can't wait for a worker to formally invoke their refusal rights if you've already identified the hazard. The obligation is yours.

Host: What's one practical thing supervisors should be doing every shift that they often skip?

Guest: Pre-shift hazard assessments. Not a lengthy formal document every time, but the habit of walking the work area before the crew starts — seeing what's changed, what's different today, what conditions affect the planned work. That 10-minute walk, done consistently, is the foundation of demonstrable due diligence. And if you spot something significant, write it down: what you saw, what you did, the date and time.

Host: And toolbox talks?

Guest: Toolbox talks are valuable because they're documented communication — evidence that you identified a specific hazard and discussed it with your specific crew before work started. Keep it brief: a signature sheet, a note on what was covered, date and location. That's your record.

Host: What if something still goes wrong despite all of those steps?

Guest: Then your record shows you were doing your job. Due diligence is not a guarantee that nothing bad will happen. It's proof that you took every reasonable step to prevent it. Courts understand that workplaces carry inherent risk. What they ask is whether the person in charge made reasonable decisions with the knowledge and authority they had.

Host: That's a really clear distinction. Thank you.

Guest: The bottom line is simple: know your hazards, take consistent action, and keep a record. That's what due diligence looks like on the ground.

[OUTRO]

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