Figure 2. ALARP principle

Text Description of Figure:

Figure two shows an inverted pyramid this is divided horizontally into three regions. The top region represents the greatest level of risk (as demonstrated by the greatest area). The line separating this first region from the second region underneath is known as the Basic Safety Limit. Risks in the top region are labelled as being 'generally intolerable '. In this region risks cannot be justified except in extraordinary circumstances.

The second region is delineated by the Basic Safety Limit (at the top) and another line separating it from the third region. This lower line is called the Basic Safety Objective. This second, middle, region is the ALARP (As Low As Reasonably Practical) or tolerable region. Towards the upper part of the region risk management may be aimed at driving risks towards the broadly acceptable region (the third region). Residual risk is tolerable only if further risk reduction is impracticable.

The third, bottom, region is called the 'Broadly Acceptable Region '. The bottom of the region forms the apex of the inverted pyramid, representing negligible risk. In the 'broadly acceptable region ' risk reduction is not likely to be required as the resources needed are likely to be grossly disproportional to the reduction that will be achieved.