Under the model Work Health and Safety (WHS) laws adopted by most Australian states and territories, every business operator is a Person Conducting a Business or Undertaking (PCBU) with a primary duty of care to ensure, so far as is reasonably practicable, the health and safety of workers and others affected by the work.
This duty applies regardless of business size — a sole trader has the same legal obligations as a large corporation, scaled to the nature and risks of their work. "Reasonably practicable" means what is reasonably able to be done, considering the likelihood and severity of the risk, what the person knows or ought to know about the risk, the availability of ways to eliminate or minimise it, and the cost of doing so.
Core obligations include: identifying hazards and assessing risks in your workplace, implementing controls to eliminate or minimise risks (following the hierarchy of controls), providing information, training, instruction, and supervision to workers, maintaining the workplace in safe condition, monitoring the health of workers and workplace conditions, and consulting with workers on safety matters.
You must also have a system for reporting and recording notifiable incidents (death, serious injury or illness, dangerous incidents) to your state regulator within specified timeframes. Failing to notify a notifiable incident is an offence.
For businesses with employees, you need a WHS policy, documented safe work procedures for high-risk activities, an injury management and return-to-work process, and emergency plans. Even sole traders should document their safety procedures — it demonstrates due diligence if an incident occurs.