Australia: Work health and safety in NSW: the PCBU's duty to do what is "reasonably practicable"

In brief - Employer duties framed in terms of reasonable practicability

The new Work Health and Safety Act 2011 (NSW) (WHS Act) defines the duties of a Person Conducting a Business or Undertaking (PCBU) in terms of what is "reasonably practicable".

Reasonable practicability and reversal of the burden of proof

Under the WHS Act, PCBUs must ensure, so far as is reasonably practicable, that the health and safety of workers and any other persons is not put at risk from work carried out as part of the PCBU's business. The absolute nature of each of the PCBU duties imposed by the new Act is qualified by the concept of reasonable practicability.

This is a dramatic change to the previous position in NSW, where the duties were imposed in absolute terms and defendants were in a sense guilty until they could prove their innocence.

The introduction of reasonable practicability has the effect in NSW of reversing the burden of proof, making it now the task of the prosecutor to establish that the PCBU has not done what is reasonably practicable, rather than the PCBU having to prove that compliance with a duty was not reasonably practicable as a defence.

WHS Act outlines safety objectives to be reached

The WHS Act is what is called performance based legislation. It provides an outline of the safety objectives to be reached by a duty holder, rather than prescribing the ways in which particular hazards should be controlled. Deciding what is reasonably practicable in any given set of circumstances is not always easy.

However, PCBU duty holders can find some guidance in the Victorian experience as the Occupational Health and Safety Act in Victoria has qualified its employer duty with the concept of reasonable practicability since 2004. Before that, the duty was qualified by the not too dissimilar term "practicability".

Fundamental purpose of WHS Act is prevention

We know from Victorian cases such as DPP v Esso that the test of reasonable practicability is an objective one and that it is to be judged by the standard of behaviour expected of a reasonable person in the duty holder's position. My advice is that you should assume that the reasonable person is someone who is proactive in health and safety.

As Justice Cummins did when sentencing Esso and considering the question of practicability, we need to keep in mind that the fundamental consideration or purpose behind work health and safety legislation is prevention. So apply the test of reasonable practicability with the purpose of prevention in mind.

Employers responsible for safety of those who work for them

The words of another Victorian Supreme Court Judge in describing the test of practicability are also helpful. In Holmes v R E Spence & Co (1992), Justice Harper said:

  • Practicability does not require employers to ensure that accidents never happen but to take such steps as are practicable to provide a safe working environment.
  • In deciding whether an employer has done what is practicable in the circumstances, the Court will look at the facts of each case as practical people would look at them and not with the benefit of hindsight, nor with the wisdom of Solomon.
  • Practicability requires an active, imaginative and flexible approach to potential dangers in the knowledge that human frailty is always present.

Definition of reasonable practicability within the WHS Act

The WHS Act has not left it entirely to the courts to flesh out what PCBUs need to do in order to satisfy the standard of reasonable practicability. Section 18 of the WHS Act defines reasonable practicability as meaning that which is, or was, at a particular time reasonably able to be done in relation to ensuring health and safety, taking into account and weighing up all relevant matters including:

  • The likelihood of the hazard or risk eventuating. The greater the likelihood of a hazard or risk eventuating, the greater the significance this factor will have in the task of determining what was reasonably practicable.
  • The degree of harm possible. Again, the greater the degree of harm possible if the hazard or risk eventuated, the greater the significance this factor will have.
  • The person's state of knowledge as to the hazards and risks which exist or the controls available. This enquiry is not restricted to actual knowledge held by the PCBU, but what it ought to have known at the time.

What the PCBU should have known about a particular hazard, risk or control

How do you determine what the PCBU ought to have known or what a reasonable person in the PCBU's position would have known about a particular hazard, risk or control?

The first step would be to enquire as to whether a reasonable person would have found a particular hazard or risk within the available state of knowledge applying a hazard identification process. Would that reasonable person have then understood the nature and degree of harm a hazard or risk may cause through the process of risk assessment within the available state of knowledge?

What controls would a reasonable person have put in place to eliminate or minimise the risk or hazard within the available state of knowledge, having regard to the following sources of information:

  • The WHS Regulations
  • Other laws specific to particular hazards and risks
  • Codes of Practice
  • Publications issued by Australian OHS regulators

If no information is available from these sources, then look at:

  • Technical standards such as those published by Standards Australia
  • Industry practice and publications
  • Published scientific and technical literature

Availability and suitability of ways to eliminate or minimise risk

In considering what controls are available and suitable, the Hierarchy of Control is helpful in determining what a reasonable person would have known about the availability and suitability of safety controls which should have been put in place.

A reasonable person would put in place the most effective control available on the current state of knowledge bearing in mind the hierarchy of controls, that is:

  • elimination
  • substituting the risk with a lesser one using engineering controls
  • reducing the risk using administrative actions

If, on the current state of knowledge, elimination of the hazard or risk is possible, then a reasonable person would have known that this particular control was available and this is what will be considered to have been reasonably practicable.

If elimination not possible, then a reasonable person doing what is reasonably practicable would implement the next most effective control: they would change the risk by substituting it with a lesser risk by using engineering controls, changes to the system of work or by isolating the risk from people.

Finally, if elimination or substitution with a lesser risk is not possible, then a reasonable person would take the least effective form of control by reducing a person's exposure through administrative actions such as the provision of instruction and procedures or the use of personal protective equipment.

Taking the cost of control into account

The final factor to take into account is cost. It is only after assessing the risk and the available ways of controlling the risk, that consideration can be given to the cost of control, including whether the cost is grossly disproportionate to the risk.

In considering the cost of a particular control there should always be a clear presumption in favour of safety, so that if a PCBU is experiencing cash flow difficulties and cannot afford to implement a control which is not so disproportionate to the risk as to be clearly unreasonable, then the view will be taken that the PCBU should not be engaging in the activity that gives rise to the hazard or risk in the first place.

It would be an incongruous situation if two duty holders faced with the same risk in similar situations could have different standards of reasonable practicability imposed on them because one is in a worse financial position than the other.

What the cost factor allows to figure in the equation is the reasonableness of choosing a less costly control measure over another where both are equally effective.

This article is based on a seminar presented in Sydney in October 2012. The second part of the article will be published in the next edition of CBP Focus.

Rose Raniolo
Occupational health and safety
Colin Biggers & Paisley

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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