Industrial Safety · Explainer
Choose controls that change the risk
Use the hierarchy of controls to work through prevention options in order. Start by asking whether the hazard can be removed altogether.
When a hazard is identified, the next question is what can be changed so people are less likely to be exposed. NIOSH describes the hierarchy of controls as a way of determining which actions will best control exposures [1].
Work from stronger controls downward
- Elimination: physically remove the hazard from the job, or design it out.
- Substitution: replace it with a less hazardous material, process or method.
- Engineering controls: isolate people from the hazard through physical design or equipment.
- Administrative controls: change how the work is planned, organised or carried out.
- Personal protective equipment: protect the worker from residual exposure.
Multiple controls are often needed. The order is a prompt to examine stronger options first, not a substitute for a competent assessment of the task and the requirements that apply.
Test the control in context
Ask whether the control addresses the actual exposure path, whether it could introduce a new hazard, who will maintain it and how the crew will know it is working. A paper procedure may help coordinate a job, but it cannot physically prevent contact with a moving part.
A maintenance team must clean a mixer. Locking the drive out and verifying zero energy (an engineering and isolation measure) protects people far more reliably than a sign saying “Do not start” (an administrative measure), because it does not rely on someone else seeing and obeying the sign.
Make it dependable
Involve the people who will use and maintain the control. Define ownership, inspection and what to do if the control is unavailable. Review after changes and learn from failures or workarounds.
Before accepting a lower-level measure, ask: “Can we remove the hazard, or physically separate people from it?”
General educational material, not legal advice, a site-specific risk assessment or a work authorisation. Confirm current requirements in your jurisdiction and follow site procedures and competent advice.
References
- NIOSH. Hierarchy of ControlsUnited States
All sources opened and checked on 30 October 2026. Requirements and guidance change; always consult the current version.
Downloads & tools
PDFPre-task review sheetv1.1 · A4 · free downloadTOOLControls & learning quizEight questions on controls, isolation, confined spaces and incident learning, with explanations.Editorial status: source-checked explainer. No independent external technical review is claimed. Spotted an error? See corrections.
