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The Energy Wheel is a simple, visual hazard recognition prompt used in pre‑job briefs and field‑level risk assessments. Its use is based on the premise that every scenario with the prospect of serious harm involves unwanted contact of a receptor with an energy source and that if the user systematically scans for types of energy, they are less likely to miss hazards that may be overlooked.
The wheel contains 10 energy categories:
Gravity (falls, dropped objects, unstable loads)
Motion (moving vehicles / equipment, swinging loads, projectiles)
Mechanical (pinch / crush points, rotating parts, stored tension / compression)
Electrical (shock, arc flash, induced energy)
Pressure (pneumatic / hydraulic, vessels, trapped pressure)
Temperature (hot / cold surfaces, steam, heat stress, cryogenic exposure)
Chemical (toxic / corrosive / flammable / reactive exposures)
Biological (pathogens, bites, contamination)
Radiation (ionizing / non‑ionizing; UV / laser)
Sound (harmful noise, pressure waves)
In practice, the wheel is used to improve hazard recognition for a job by running through the ten categories and linking each to hazards and controls with special emphasis on high‑energy hazards that are the most harmful to receptors in the work area.
Here is a typical workflow:
- Pause and frame the job.
Ask:
What are we doing right now (and what changes during the job)?
What is happening around us (e.g. SIMOPS, traffic, lifts overhead)?
What could change quickly (e.g. weather, lighting, access, fatigue, schedule pressure)?
- Use the wheel to consider energy sources.
For each energy category, ask: Where is this energy present in the work area or adjacent work areas?
- For each energy source found, identify and verify controls.
Controls may be direct or supporting. Direct controls physically prevent contact of receptors with the source, or eliminate / limit the energy. Supporting controls help to use / maintain direct controls. They include procedures, signage, training, spotters, and PPE.
Controls must be verified, Quick verifications such as testing for zero energy, checking rigging, confirming isolation points, and validating exclusion zones can be used.
- Decide to proceed, add controls, or change the work plan.
Existing controls may be deemed acceptable, new or improved controls may be needed, or the method of working may need to be changed.
Here is a short example involving swapping out a pump using a forklift and disconnecting piping.
Motion: forklift travel path ➔ exclusion zone + spotter + defined route
Gravity: suspended load during lift ➔ rated rigging + no one under load zone
Pressure: trapped pressure in line ➔ isolate / bleed / verify zero energy
Chemical: residual contents ➔ drain / flush + containment + PPE as last line
Mechanical: pinch points on set‑down ➔ hands‑off placement + tag lines
The energy categories keep the team from overlooking hazards that may be obvious with hindsight, e.g. trapped pressure, pinch points, dropped loads, especially when jobs are performed under time pressure.
The Energy Wheel is often described as a cognitive mnemonic. People reliably miss certain hazard types unless prompted, so the wheel serves as a structured prompt to widen attention beyond the most visually obvious risks.
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