Introduction to Fire Safety Management

Principles of risk assessment
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As no numerical scales have been introduced with 
the above simple estimator it is diffi cult for a precise 
indication of the level of risk to be determined. Neither 
does this approach provide an easy mechanism to 
confi rm if the risk has been reduced to the lowest level 
reasonably practicable.
However, by introducing the above subjective 
estimations of the two elements of risk into a simple risk 
matrix, a qualitative assessment of risk can be made. 
Figure 5.10 is an example of a simple risk matrix.
When undertaking risk assessments for a number of 
work activities the application of a consistent method of 
qualitative evaluation of risk will allow for actions to be 
prioritised.
For example, a systematic qualitative evaluation of 
an organisation’s risk will result in some risks that are 
evaluated as ‘high’, some that are ‘low’ and some that are 
‘insignifi cant’, management decisions can then be made 
of a basis of risk vs cost. This qualitative method provides 
a basic evaluation of risk and will allow an organisation to 
consider what may or may not be considered a reason-
ably practical level of safety.
There are a number of methods for evaluating risk. 
The method applied for any particular risk will depend on 
a number of factors, such as the complexity of the activ -
ities carried out and the type and nature of the workplace.
For many of the day-to-day risks that people in the work-
place are exposed to, including fi re, a simple qualitative 
assessment will suffi ce, for more complex risks a quanti-
tative or semi-quantitative assessment may be needed.
Qualitative analysis
Qualitative analysis describes a quality of the risk. 
Typical of the qualities most often described is that of 
quantum, i.e. size or magnitude. For example, when 
assessing the means of escape in the event of a fi re, fi re 
risk has historically been rated as high, normal or low.
Qualitative analysis of risk is a subjective measure, 
based upon the risk assessor’s judgement. As with all 
methods of risk evaluation, a qualitative assessment will 
need to allow consideration of the two aspects of risk, 
i.e. the likelihood of a particular occurrence and the 
severity of the consequences.
The HSE, in its guidance document HSG65, have 
suggested a basic estimator as appropriate for a simple 
evaluation of risk. The HSE estimator, shown in Table 5.1, 
uses purely subjective measures of likelihood and uses 
RIDDOR events to ascertain the qualitative descriptors 
of the seriousness of the outcome.