Safety knowledge should be free.

The hierarchy ranks control measures from most to least effective: elimination, substitution, engineering, administrative, then PPE. Australian WHS law expects you to work down from the top — you can't jump to hi-vis vests and gloves if the hazard could have been designed out. Higher controls remove or isolate the hazard itself; lower ones rely on people behaving perfectly, which they don't.

A PCBU — a Person Conducting a Business or Undertaking — holds the primary duty of care under the Model WHS Act: to ensure, so far as is reasonably practicable, the health and safety of workers and others affected by the work. It's a broad, non-delegable duty that covers the work environment, plant, systems of work, information, training, and supervision.

A psychosocial hazard is anything in the design or management of work that can cause psychological harm — high job demands, low control, poor support, bullying, harassment, or exposure to traumatic events. Since recent regulation changes, PCBUs must identify and control these hazards the same way they would a physical one, through a documented risk-management process.

A Safe Work Method Statement is mandatory before any high-risk construction work begins — the WHS Regulations name specific categories such as working at heights, near live electrical, in excavations, or around mobile plant. It must break the task into steps, identify hazards, set controls following the hierarchy, and be signed on by every worker involved before the work starts.

It's the legal test at the heart of WHS duties. It weighs the likelihood and degree of harm against what's known about the hazard and the availability and cost of controls — but cost only outweighs risk when it is grossly disproportionate. In practice: if a reasonable control exists and isn't wildly out of proportion to the risk, you're expected to use it.