How do you describe the potential effects of hazards?
The manner in which you describe the potential effects of hazards will depend on the scope of your risk assessment. If you are analysing hazards in a community defined by a geographical area or administrative area you will use a certain set of parameters to describe the likelihood, consequences/ effects (for example, extent/number of services disrupted, number of disrupted/homeless persons). If you are analysing hazards in an industry, or a commercial or other activity you may use other parameters (for example, value of lost production, clean-up costs).
Determining likelihood and consequence
Once we have described the hazards, community and environment and from those determined the vulnerability of the community/ environment and identified the associated risks, we can then work on estimating the predicted the likelihood and expected consequences of the risk. This estimation of likelihood and consequence can be either qualitative or quantitative and there are numerous models and methods available to us to use. Among these are the use of physical models, computer generated models and simulations, mathematical models and statistical modelling and intuitive modelling, based on the understanding of behaviour through experience, knowledge and understanding of processes etc.
One thing that we must ensure when analysing risks is that they should all be analysed and described in the same terms. Using differing methods to describe different risks will make deciding on priorities for treatment down the track much more difficult, if not impossible.
The Emergency Risk Management Applications Guide suggests that likelihood should be determined ' qualitatively (without using numbers or probabilities) ' (EMA, 2000b). The reason given, that very few risks will be quantifiable. The guide provides one method of determining the likelihood and consequence of a risk. This is explained in Activity 7.1.
Read the sections dealing with analysis of risks in your texts, Emergency Risk Management Applications Guide and AS/NZS 4360: 2004 Risk Management Standard. Think about how you will analyse the risks within your risk assessment project and how you will document the likelihood and consequences of the risks you have identified. Jot your ideas down and keep them with your project work. Deciding on alternate parameters as a basis for description
So how do we go about identifying alternate suitable parameters? Let us take a community in a geographic area for a moment. Table 7.1 shows some of the parameters that could be considered.
|
Descriptive parameters for the potential effects of hazards
| Losses | |||
| Consequences | Measure | Tangible | Intangible |
Deaths |
Number of people |
Loss of economically active individuals |
Social and psychological effects on remaining community |
Injuries |
Number and injury severity |
Medical treatment needs, temporary loss of economic activity by productive individuals, reduced ability of medical facilities in dealing with normal cases |
Social and psychological pain and recovery |
Disruption of normal services |
Services disrupted, location, degree of damage, down time |
Inconvenience and harm to service users |
Concern over loss of service |
Property and infrastructure damage |
Property type, degree of damage and location |
Replacement and repair cost |
Cultural losses |
Disruption to economy |
Number of working days lost, volume of production lost, amount of trade lost |
Value of lost production |
Opportunities, competitiveness, reputation |
Social disruption |
Number of displaced and homeless persons |
Temporary housing, relief, economic production |
Psychological. social contacts, cohesion, community morale |
Environmental damage |
Scale and severity |
Clean-up costs, repair cost |
Consequences of poorer environment, health risks, risk of future disaster |
Source: Adapted from a table called 'Loss Parameters for Risk Analysis', An Overview of Disaster Management, United Nations Disaster Relief Organisation, Geneva, 1992, p. 66.
Transforming the list of potential parameters to descriptions
So far, so good. We have a list of possible parameters on which to base our description of potential effects. If we assume for the moment that your risk assessment report is based on a community defined by a geographical area, what next? How do you decide on those parameters you will use in your report? How will you translate them into a description? I believe that firstly you have to inform your planning group of the means by which you intend to describe the potential effects of your hazards, explain each parameter you wish to use, and allow them to modify the parameters if they wish. In Activity 7.1, you were asked to draft up a possible risk analysis using the Emergency Risk Management Applications Guide method as a basis. Would that analysis be enhanced through the inclusion of alternate descriptions of effects, thereby complementing and adding qualitative support to your initial risk analysis?
In order to do this you will need to examine each hazard in detail, going through each of the parameters, and estimating the degree of loss in relation to each parameter, and the nature of any tangible or intangible effects or losses.
Even if your risk analysis report is based on a community other than one defined by a geographic area, the principles are the same-work through your planning group, identify and discuss the parameters by which you can comprehensively identify the effects of the hazards and thus analyse the risks in the most effective way.
The results of your examination should be documented immediately, so that you do not forget why you/your group chose to give a certain answer to the questions posed by those parameters.