How strong is your control?

Energy and harm

Long before modern safety systems, James Gibson observed that injury occurs when energy is transferred to the human body in amounts or at rates beyond its tolerance. William Haddon later expanded this into the Energy Damage Model: harm is not random, it is the result of uncontrolled energy transfer.

Once you accept that framing, a more revealing question emerges:

For any given hazard, what must happen for the energy to reach someone, and what prevents that transfer?

Not all controls work the same way

Controls differ in how they answer that question.

Some controls prevent harmful energy transfer without requiring human judgement. A fixed guard, physical separation, or engineered isolation removes the pathway. No detection is required. No interpretation is needed. The barrier simply stands between energy and exposure.

Other controls automatically interrupt the pathway. Interlocks, pressure relief devices, and fail-safe shutdowns reduce reliance on human cognition at the critical moment.

Then there are controls that depend almost entirely on people.

The limits of administrative controls

Administrative controls, by their nature, often do. They rely on workers noticing information that something is wrong, interpreting that signal correctly, deciding what it means in context, and then acting appropriately and in time.

In high-energy systems, the tolerance for error can be very small. A timely, correct action can prevent catastrophe. A well-intended action that is slightly late, slightly misread, or slightly misapplied can still leave someone in a difficult position, sometimes with serious consequences. Outcomes can turn on seconds, angles, sequence, and proximity, not effort.

That’s why there is often a fine line between being seen as a hero and being seen as a fool. The difference is not character. It is the narrowness of the margin, and the unforgiving nature of uncontrolled energy.

Guidance such as the Queensland Government’s PErforM manual recognises this reality, noting that administrative controls are best used as part of a comprehensive control strategy, or as an interim measure while stronger design controls are developed.

Why layered protection matters

In practice, effective systems rely on layers. Charles Perrow described this as defence in depth. James Reason illustrated it as layered barriers. The principle is simple: no single control should be expected to carry the entire burden of preventing catastrophic energy transfer.

Consider driving a vehicle. Protection does not rely on a single instruction to “be careful”. You are surrounded by layers: vehicle engineering, braking systems, crash structures, road design, separation distances, traffic lights, signage, licensing, training, enforcement, and behavioural norms. Some controls are engineered. Some are administrative. Some are behavioural. Together they reduce the likelihood that kinetic energy becomes fatal.

Where risk registers can mislead

This is where many risk registers quietly mislead. A high-energy hazard may be assessed as controlled because a procedure exists, training has been delivered, or signage has been installed. The likelihood score drops. The energy does not.

So the issue is not whether a control exists. It is whether the control interrupts the energy pathway reliably.

Three questions leaders should ask

For hazards capable of fatal or life-changing harm, leaders should be able to answer:

1. Which controls prevent or isolate the energy by design?

2. Which controls automatically interrupt the pathway if conditions change?

3. Which controls rely on detect–decide–act performance at the critical moment?

The real test of control strength

The more your system depends on the third category for high-energy hazards, the more your risk reduction depends on precision under pressure.

Administrative controls have a place. But they should rarely be the primary line of defence against catastrophic energy.

Authority in risk management comes from understanding control strength, not counting controls.

When the energy is unforgiving, control strength matters more than good intention.

PErforM source "Office of Industrial Relations, Australia. (2013). Participative Ergonomics for Manual Tasks (PErforM) Handbook."