WHS Act 2011: A Complete Overview for Australian Businesses

The Work Health and Safety Act 2011 is the principal legislation governing workplace health and safety across most Australian jurisdictions. It replaced the patchwork of state-based occupational health and safety acts with a harmonised national framework. The Act establishes duties for persons conducting a business or undertaking (PCBUs), officers, workers, and other persons at the workplace. It creates a tiered offence structure with penalties scaled to the seriousness of the breach, ranging from Category 3 offences for simple duty failures to Category 1 offences involving reckless conduct that exposes a person to the risk of death or serious injury.

The Act applies to all workplaces in New South Wales, Queensland, South Australia, Tasmania, the Northern Territory, the Australian Capital Territory, and at the Commonwealth level. Western Australia adopted the WHS Act in 2022 with some modifications. Victoria remains the only jurisdiction operating under its own Occupational Health and Safety Act 2004, although its duty framework is broadly similar. Understanding which version of the Act applies in your jurisdiction is essential because penalty amounts, specific provisions, and transitional arrangements vary between states.

Section 19 of the WHS Act imposes the primary duty of care on every person conducting a business or undertaking. The duty requires a PCBU to ensure, so far as is reasonably practicable, the health and safety of workers who carry out work for the business and of other persons who may be affected by the work. This is a positive, proactive obligation — it requires the PCBU to take steps to identify hazards, assess risks, and implement controls before harm occurs, not merely react after an incident.

The standard of 'so far as is reasonably practicable' is defined in section 18 of the Act. It requires consideration of the likelihood of the hazard or risk occurring, the degree of harm that could result, what the person knows or ought reasonably to know about the hazard and ways of eliminating or minimising it, the availability and suitability of controls, and the cost of the controls (but only after assessing the extent of the risk and whether the cost is grossly disproportionate to the risk). This last factor means cost cannot be used as a blanket excuse for inaction — a PCBU must demonstrate that the expense of the control measure is grossly disproportionate to the risk, a very high threshold.

Section 27 imposes a personal duty on officers of a PCBU to exercise due diligence to ensure the PCBU complies with its WHS duties. An officer includes a company director, a partner, or any person who participates in making decisions that affect the whole or a substantial part of the business. This duty cannot be delegated. An officer who relies solely on safety managers to handle compliance without exercising personal oversight is exposed to prosecution.

Due diligence requires the officer to acquire and keep up to date with knowledge of WHS matters, understand the nature of the business operations and the hazards and risks associated with those operations, ensure the PCBU has appropriate resources and processes to eliminate or minimise risks, ensure the PCBU has appropriate processes for receiving information about incidents and hazards and for responding to that information in a timely way, ensure the PCBU has and implements processes for complying with its WHS duties, and verify the provision and use of the resources and processes mentioned above. Officers face personal penalties of up to $690,000 for Category 2 offences under CPI-indexed amounts for 2025-26.

Workers have both duties and rights under the WHS Act. Section 28 requires workers to take reasonable care for their own health and safety, take reasonable care that their acts or omissions do not adversely affect the health and safety of others, comply so far as reasonably able with any reasonable instruction given by the PCBU, and cooperate with any reasonable WHS policy or procedure that has been notified to them.

Workers also have the right to cease unsafe work under section 84 without fear of discrimination. If a worker has a reasonable concern that performing work would expose them to a serious risk arising from an immediate or imminent exposure to a hazard, they may cease the work and must notify the PCBU as soon as practicable. The PCBU must not direct the worker to resume work until the risk has been addressed. Workers also have the right to elect health and safety representatives under Part 5 of the Act and to be consulted on WHS matters that affect them under section 47.

The WHS Act establishes a three-tier offence structure. Category 1 offences (section 31) apply when a duty holder is reckless as to a risk of death or serious injury — maximum penalties are $3.46 million for a body corporate and $690,000 or five years imprisonment for an individual. Category 2 offences (section 32) apply when a duty holder fails to comply with a health and safety duty and the failure exposes a person to the risk of death or serious injury — maximum penalties are $1.73 million for a body corporate and $345,000 for an individual. Category 3 offences (section 33) apply to a simple failure to comply with a health and safety duty — maximum penalties are $865,000 for a body corporate and $173,000 for an individual. All penalty amounts cited are the 2025-26 CPI-indexed figures.

Inspectors appointed under the Act have broad powers including the power to enter workplaces, require the production of documents, issue improvement notices and prohibition notices, and seize evidence. The regulator can also accept enforceable undertakings as an alternative to prosecution for certain offences. Since 10 June 2020, WHS fines in NSW have been uninsurable, meaning a PCBU cannot take out insurance to cover the cost of WHS penalties. This makes compliance a direct financial imperative for every business.