The ‘User-information system’ relationship: A reliance-based safety classification

The safety management of risks associated with a Safety Related Information System (SRIS) is problematic. This is because, when a human user makes an information-based decision it is difficult to ascertain a measurable correlation between the erroneous behaviour of the Information System (InfoSys) and the subsequent contributory effects within an accident chain. This paper proposes a safety-related classification approach for InfoSys, which is based upon the ‘reliance’ aspect of the ‘user-InfoSys’ relationship. The aim such a classification approach is to support the derivation of safety design requirements for InfoSys, whose erroneous outputs have the potential to contribute to harm, in a more appropriate manner.