P and S Factors

P and S Factors are used to assess the holding capacity of a ground.

For both seated and standing accommodation, the holding capacity will also be assessed according to its:

physical condition, or (P) Factor, and
safety management procedures of that area, or (S) Factor.

A single (P) Factor and a single (S) Factor should be set for each separate area of the spectator viewing facilities.

To help in the assessment of (P) and (S) Factors, it is recommended that each should be given a numerical value. This value should be quantified as a factor of between 0.0 and 1.0:

Where the physical condition of the viewing accommodation is of a high standard, a (P) Factor of 1.0 should be applied.
Where the physical condition is extremely poor, a factor of 0.0 should be applied (which, as explained below, would have the effect of imposing a zero capacity on the area).

The same considerations should then be made in respect of the safety management competence with the same outcome applied.

An intermediate assessment might result in, for example, a (P) Factor of 0.6, or perhaps an (S) Factor of 0.8.

This lower number of 0.6 should then be multiplied by the capacity identified for the seated/standing accommodation, as identified in points (a) and (b) above. The lower number should then be noted as the holding capacity for the section of a ground or ground as a whole.

These figures are used to determine the holding capacity, namely the number of spectators that can safely be accommodated in the area concerned.

The (P) and (S) Factors should be assessed by a competent person with knowledge and understanding of the ground concerned, its operation and the general principles of safety.

Where any part or parts of a ground are covered by a safety certificate issued by the local authority ground management’s assessment of the (P) and (S) Factors should be included with the capacity calculations when they are forwarded to the local authority for review and validation.

Full details of calculating the safe capacity of a ground, including the holding capacity is available in the Green Guide.

Each sports ground is different. Therefore, the Green Guide does not attempt to place specific values on any of the elements that are likely to be considered when assessing (P) and (S) Factors.

This is because assessments should not aim to create a cumulative scoring system in which values for individual elements are simply added together. Instead, the assessment should reflect a considered and reasonable overall judgement of the physical condition and safety management of the area in question.

We have published indicative questions and capacity calculation worked examples, as free annexes to the Green Guide, which provide further detail and support on calculating the (P) and (S) Factors.