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As low as reasonably practicable

Below are the two extremes of risk:

Risk is negligible and can be accepted without specific treatment other than monitoring.
Risk is intolerable and the activity must cease, unless risk can be reduced.

However, most risks do not fall into these two extremes. They lie somewhere in the middle, and it becomes necessary to consider how you can reduce the risks to a level 'as low as reasonably practicable' (ALARP).

What does 'as low as reasonably practicable' mean?

The ALARP principle new window 77k encourages you to consider the benefits of reducing a risk against the costs involved (time, trouble, money, resources etc.).

For example, imagine you have identified a risk that is low to moderate. You have systems in place to deal with the risk and there are no real benefits of reducing the risk further. If in order to reduce the risk further you must work night and day and spend every dollar at your disposal, would you do it?

The ALARP principle is when you balance up the benefits of reducing the risk, and think about ways you can reduce the risk level to a reasonable level, at a reasonable cost.

Definitions of 'reasonably practicable'

Defining the term 'reasonably practicable' can help you gain a deeper understanding of the ALARP principle.

Definition 1 - Queensland Workplace Health and Safety Act 1989

The Queensland Workplace Health and Safety Act 1989 provided the following definition of 'practicable'.

the severity of any potential injury or harm to health or safety that may be involved, and the degree of risk that exists in relation thereto
the state of knowledge about the injury or harm to health or safety that may be involved, about the risk of that injury or harm to health or safety occurring and about any ways of preventing, removing or mitigation that injury, harm or risk
the availability and suitability of ways to prevent, remove or mitigate that injury or harm to health or safety or risk, and
whether the cost of preventing, removing or mitigating that injury or harm to health or safety or that risk is prohibitive in the circumstances.

Definition 2 - Legal opinion

A legal opinion from a barrister active in the Occupational Health and Safety area in Victoria provided the following definition of reasonably practicable.

'Reasonably practicable' having regard to:

the severity of the hazard or risk in question
the state of knowledge about that hazard or risk and any ways of removing or mitigating that hazard or risk
the availability and suitability of ways to remove or mitigate that hazard or risk, and
the cost of removing or mitigating that hazard or risk.

This definition relates to the duties imposed in the Act. It means ALL these factors must be taken into account when determining whether the duty has been met rather than only looking at any single factor, e.g. cost.

Definition 3 - Lord Asquith

The following opinion given by Lord Justice Asquith in 1949 is offered as the cleanest and simplest definition of our duty to do things in so far as is reasonably practicable. If we base our decisions on the following definition then we will have a strong argument to suggest we have discharged our duty of care.

'Reasonably practicable' is a narrower term than 'physically possible' and it seems to me to imply that a computation must be made by the owner, in which the quantum of risk is placed on one scale and the sacrifice involved in the measures necessary for averting the risk (whether in money, time or trouble) is placed in the other; and that if it be shown that there is a gross disproportion between them - the risk being insignificant in relation to the sacrifice - the defendants discharge the onus on them. Moreover, this computation falls to be made by the owner at a point of time anterior to the accident.
Source: Edwards v National Coal Board (1949) 1 KB 704 at 712, CA, per Asquith LJ

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