Risk modelling of fires and explosions in open-sided offshore platform modules

Incidents involving fires and explosions present a major hazard to the workforce on offshore oil and gas platforms. Following the Piper Alpha Disaster in 1988, platform operators for the UK sector are required to submit safety cases for approval by the Health and Safety Executive. A key requirement of these safety cases is that hazards associated with an accidental release of hydrocarbons have been demonstrated to be as low as reasonably practicable. This paper aims to describe a process for estimating the expected number of fatalities on offshore platforms with open-sided modules using a Monte Carlo simulation method implemented within the SAROS (Safety and Reliability of Offshore Structures) software. The process involves estimation of the frequency and magnitude of jet fires, pool fires and explosions. This is combined with the distribution of the workforce over the platform at the time of the incident to predict the risk of fatality.