Workplace health and safety and the importance of the hierarchy of controls

Why was the Hierarchy of Controls created?

Injury and illness have remained stubbornly resistant to the expensive and structured endeavours directed to overcome this costly and complicated problem. These costs include the enormous pressures on business, the community and workers both in recurrent injuries and in the systems that attempt to overcome them. After early improvements up to 2000 by 2008/9 safety improvements had plateaued and injury occurrence had become stubbornly fixed and was beginning to again increase and people were saying that ‘it is as good as it was ever going to get’.

In 2012 a paradigm shift occurred, culminating in a new ‘systems’ approach that continues to evolve today, designed to tackle this recalcitrant problem. The lynchpin of this approach is trifold: collaboration, accountability and the hierarchy of controls. To understand this third and most crucial concept we need also to understand this ‘systems approach’, and where it came from. A systems approach was evolving across society in a number of areas including finance and management and so to extend this into the legislation was a natural and necessary step. Systems approach treats an organisation as a system, one that interacts with its environment.

In 2008 the Commonwealth Government and all the States and Territories agreed to harmonise their workplace health and safety laws and in 2009 the Federal government established Safe Work Australia. This was a jointly funded endeavour tasked to overcome the recurrent problem of injury and illness in the Workplace . This was the first time all jurisdictions had made a formal commitment to collaborate and harmonise their approaches to safety. Their significant efforts culminated in the delivery of harmonised model legislation and including the Model WHS Act in 2012.

The purpose of their approach has been to improve communication on safety matters in every workplace, to foster a structured approach to safety that now begins with a structured organisational commitment. This derives in part from;

  1. the direct obligation on those with financial and managerial control to assume responsibility for safety, and
  2. implementing a structured assessment of risk, a systems approach
  3. a hierarchy in acceptable controls to that risk.

Managing risk then has since become a core element of every WHS system. Section 18 requires a PCBU to ensure as far as reasonably practical, the health and safety of workers and others by considering and weighing up relevant matters set out in that section.

No longer is it enough for a business to deliver PPE or give staff training to avoid a significant risk. Now they must first attempt to eliminate that risk in toto. The hierarchy of controls approach was decisively inserted into the legislated obligation to manage risk. When likened to an embryo we see its’ potential in the differences it generates.

This obligation is continually evolving and has led to a number of different models of workplace health and safety management systems . Within workplaces it is leading to an improved focus and clarity to, not just put into place a control, but to try and first eliminate the risk altogether.

What is the Hierarchy of Controls?

There are many representations of how the hierarchy of controls works what is consistent is the reluctance to accept lower level controls when higher level controls are practical and effective. And to prove it – people are now going to gaol in the worst of breaches, and organisations are getting significant fines in others. Where it is applied we are seeing the embryonic evidence of safety by Design. This catch phrase coined by the SafeWork Australia has led businesses to look for equipment that has inbuilt safety features rather than a need to add them in retrospectively.

For the first time in 2012, legislators introduced into the WHS Act key WHS principles utilised by experts in many industries. Concepts of a System’s approach began to emerge in smaller businesses and the central tenant to these principles is the obligation to use the ‘hierarchy of Controls’ to manage those risks.

The Hierarchy of Controls mandates that controls are ranked from the highest level of protection and reliability to the lowest according to their effectiveness on first eliminating and then controlling the hazards that present at their source. The priority is to eliminate the identified hazard so far as is reasonably practicable, or if that is not possible, minimising risks as far as reasonably practicable. Importantly the obligations rest with the officers and directors.

This means the PCBU must always aim to eliminate the hazard, which is the most effective control.

If elimination is not reasonably practicable, the PCBU must minimise the risk so far as is reasonably practicable by doing one or more of the following:

  • substituting (wholly or partly) the hazard creating the risk with something that creates a lesser risk
  • isolating the hazard from any person exposed to it
  • implementing engineering controls.

If a risk still remains, that remaining risk must be further minimised, so far as is reasonably practicable, by implementing administrative controls or through the use of personal protective equipment (PPE).

Administrative controls are work methods or procedures that are designed to minimise exposure to a hazard (e.g. the use of training or instructions and placing signs to warn people of a hazard).

Administrative controls and PPE should only be used:

  • when there is no other practical control measure available (as a last resort)
  • as an interim measure until a more effective way of controlling the risk can be used
  • to supplement higher level control measures (as a back up).”


  1. “Intergovernmental Agreement for Regulatory and Operational Refrm in Occupational Health and Safety” (PDF). Council of Australian Governments. 3rd Jul 2008. Archived from the original (PDF) on 27th Mar 2015. Retrieved 22nd Feb 2019
  2. WHS Model Laws 2012
  3. A  PCBU is
  4. Section 36 WHS Regulations.
  5. WHS a Management Guide, Chapter 4, p75
  6. Qld jail example
  7. Qld example
  8. Hierarchy of Controls section ??
  9. Archer et al, p126
  10. Worksafe Qld, chapter 3. Control the risks, retrieved from
  11. Worksafe Qld, chapter 3. Control the risks, retrieved from
  12. s4.1. The hierarchy of control measures, Model Code of Practice How to manage work health and safety risks, SafeWork Australia retrieved from on 22 February 2019; and s4.1 The hierarchy of risk control, How to manage work health and safety risks Code of practice 2011 (PN11157), WHS Qld, 2011 retrieved 22 February 2019.
  13. s4.1 The hierarchy of risk control, How to manage work health and safety risks Code of practice 2011 (PN11157), WHS Qld, 2011 retrieved 22 February 2019
  14. Number of serious claims by mechanism of injury or disease, 2000–01 to 2014−15p,
  15. Injury Occurrence for body stressing. Injury Occurrence for muscular stress