4.3 Hierarchy of Controls

[Scene: Liza and John walking through the shop floor. Pyramid graphic appears side-by-side as they talk, each level lighting up as they explain it.]
John:
Liza, I heard about something called the Hierarchy of Controls. What’s that all about?
Liza:
It’s a system we use to pick the most effective way to control risk—from best to least effective. Think of it like a safety pyramid.
[Visual: Pyramid graphic appears labeled 1–5. Level 1 lights up.]
Liza:
🔺 1. Elimination – Remove the hazard completely.
Example: Instead of climbing up a tall mast to clean a light, we bring the light down and clean it safely on the ground.
[Level 2 lights up.]
Liza:
🔺 2. Substitution – Replace something dangerous with something safer.
Example: Swap out chlorine gas with hypochlorous acid to avoid hazards of chlorine gas leakage from storages.
[Level 3 lights up.]
Liza:
🔺 3. Isolation – Involves separating workers from hazards using physical barriers or distance. 
Examples: include using guardrails to prevent falls, installing machine guards, or using remote controls to operate machinery. 
[Level 4 lights up.]
Liza:
🔺 4. Engineering Controls – Build something that keeps people away from the hazard.
Example: For electrical risks, use ELCBs or VRDs to cut power in case of faults.
[Level 5 lights up.]
Liza:
🔺 4. Administrative Controls – Change how people work.
Example: Don’t make one operator work 8 hours straight. Use two people for 4 hours each, or rotate jobs every few months to prevent fatigue and strain.
[Level 6 lights up.]
Liza:
🔺 5. PPE – Personal Protective Equipment.
Example: Gloves, goggles, ear protection. Important, yes—but this is your last line of defense, not the first.

John:
So we always try to eliminate or isolate the hazard first—then go down the list?

Liza:
Exactly. The higher up the pyramid, the safer and more reliable the control.
John - Just to be mindful and cautious followings are not additional control measures -
PPE and administrative controls.
John - So You mean to say PPE, SOP, Training, TBT, PTW are not to be considered as additional control measures?
Liza - Yes John, they are not the additional control measures. Hence as per the HOC, top four in the pyramid (eliminate, substitute, isolate, and engg control) should only be used to mitigate the high residual risk.
[Visual: Full pyramid lights up. Text overlay: “Choose smart. Control better. Stay safe.”]
Liza (closing):
Think smart. Control hazards at the source whenever possible—and use PPE to back up everything else.