Part 3 of the Act deals with the 'general duties' relating to health and safety - duties of employers, employees, and so on. It is preceded by Section 20, which covers the 'concept of ensuring health and safety'.
To avoid doubt, a duty imposed on a person by this Part or the regulations to ensure, so far as is reasonably practicable, health and safety, requires the person -
(a) to eliminate risks to health and safety so far as is reasonably practicable; and
(b) if it is not reasonably practicable to eliminate risks to health and safety, to reduce those risks so far as is reasonably practicable.
s20(2) then outlines what 'so far as reasonably practicable' means:
"To avoid doubt, for the purposes of this Part and the regulations, regard must be had to the following matters in determining what is (or was at a particular time) reasonably practicable in relation to ensuring health and safety -
(a) the likelihood of the hazard or risk concerned eventuating;
(b) the degree of harm that would result if the hazard or risk eventuated;
(c) what the person concerned knows, or ought to reasonably know, about the hazard or risk and any ways of eliminating or reducing the hazard or risk;
(d) the availability and suitability of ways to eliminate or reduce the hazard or risk;
(e) the cost of eliminating or reducing the hazard or risk."
This does not mean that if the cost of eliminating or fixing something is very high, then it does not need to be done. What Chris Maxwell said in his review of the 1985 OHS Act was that if something was capable of being done, then it should be done - and cost was only one aspect that had to be considered.
WorkSafe Victoria has produced a guideline (made under Section 12 of the OHS Act, 2004): How WorkSafe applies the law in relation to Reasonably Practicable which explains the concept and its application. HSRs should ensure they have a copy for reference.
Last amended June 2019