Decision support tool

System assessment

The aim of a system assessment is to obtain a reliable prediction about the safety of the system and the measures which need to be continued, improved or newly established to ensure this. A system assessment comprises:

Hazard analysis

Here, an analysis of all potentially occurring hazards in the supply system as well as their causes (for cyanotoxins e.g. eutrophication of the water body) or events, which present a hazard (e.g. longer periods of stable stratification of the water body) is undertaken. This analysis also comprises the evaluation of already existing measures to control the hazards: are the measures in general suitable for their designated use or are further measures necessary? Are the control measures being operated reliably to ensure a sufficient control of the hazard at any time?

Risk assessment

By assessing the extent of a hazard and the probability of its occurrence, possible health risks in the supply system can be assessed relative to each other. This enables a prioritisation of the risks and measures to be carried out. Often, the attempt of this assessment reveals information gaps which need to be filled before a sufficiently valid assessment is possible.

System assessment is an iterative process, which can hardly be displayed linearly. Eventually, you may wish to revise your assessment after you have dealt with the control measures and repeated the validation of your measures and/or of your risk assessment. We thus recommend eventually performing a second round of the steps described here.