Chemical risk & exposure
Why PPE is the last line of defence: the hierarchy of controls for chemicals
Gloves and respirators matter, but they only work when every other control has already been tried. A site that starts with PPE has its priorities upside down.
A common misconception is that personal protective equipment (PPE) is the first answer to a chemical hazard. In reality, PPE is the last line of defence. It is used only once more effective controls have been applied, and to deal with the risk that remains.
The hierarchy, from most to least effective
- Elimination: remove the hazardous chemical or process entirely. Example: switching to automated tank cleaning, so no one enters a tank with solvent vapour.
- Substitution: use a less hazardous chemical or form. Examples: water-based paints instead of solvent-based ones; pellets or slurry instead of dry powder; a product without a carcinogen such as benzene or hexavalent chromium.
- Engineering controls: isolate people from the hazard. Examples: closed transfer and dosing systems; local exhaust ventilation at mixing points; fume cupboards; enclosed bag-slitting stations; bunds and drip trays.
- Administrative controls: change how the work is done. Examples: safe operating procedures, permits to work, job rotation, signage, training, restricted access, keeping eating and smoking well away from chemical areas.
- Personal protective equipment: protect the individual. Examples: chemical-resistant gloves selected from SDS Section 8, goggles or face shields, respirators with the right cartridges (A2 for organic vapours, P3 for dust), chemical-resistant coveralls and boots.
Why PPE is the weakest control
- It only works if it is the right type, fits, is worn correctly and is in good condition.
- It protects only the wearer, not people nearby or the environment.
- It can give a false sense of security, especially with the wrong glove material or an expired cartridge.
- It is uncomfortable in hot climates, so people use it inconsistently.
Using PPE well. PPE remains essential for the risk that is left over and for emergencies. Choose it from SDS Section 8 and the task risk assessment. Fit-test respirators. Train people how to put it on and take it off. Inspect it, and replace it on a set schedule.
What to do
- For each high-risk task, record which level of the hierarchy each control belongs to.
- Before accepting "PPE only", ask whether elimination, substitution or an engineering control is reasonably practicable.
- Review controls after incidents, near misses and air-monitoring results.
- Check PPE use, not just whether it has been issued.
How INRC can help
Our occupational health and safety assessments work down the hierarchy of controls for each high-risk task, and our training covers PPE selection, fit and correct use. Contact us to discuss your site.
This article is general guidance, not legal advice. Check current legislation and regulations for your specific project.