Application of HAZOP to Programmable Systems

The increased use of systems containing software in safety-related applications gave rise to the need to use established safety engineering principles in developing such systems. A key early activity is to identify the hazards that can arise from use of the system. We decided to explore the use of a technique traditionally used in the chemical industry called HAZOP (hazard and operability study).

Over a number of client projects, mainly in the rail and healthcare fields, we successfully migrated the principles of HAZOP to the domains of software and electronics. The UK Ministry of Defence then placed a contract with us to develop a set of guidelines for the application of HAZOP to programmable electronic systems. This was subsequently published as DEF-STAN 00-58.

Prompted by positive feedback to the standard, the main authors of the standard then decided to expand on the material in the standard and produce a book. The book describes HAZOP and explains its efficient and effective use based on real experience. The book was published by Wiley in 1999 as 'System Safety: HAZOP and Software HAZOP' with ISBN 0-471-98280-6 and has become the standard reference book on the subject.