The identification of hazards in chemical plants has become increasingly important. Not only have plants become larger and more complex, but some countries now have regulations requiring that some form of formal hazard identification be performed. Environmental regulations have been tightened as the public has become aware of the dangers posed by large chemical plants. One of the most popular techniques for hazard identification is a hazard and operability study (HAZOP).

A hazard and operability study (or HAZOP) is a systematic, critical examination by a team of the engineering and operating personnel with the intention to assess the hazard potential of individual items of equipment and the consequential effects on the facility as a whole. The essential feature of the HAZOP Study approach is to review process drawings and/or procedures in a series of meetings, during which a multidisciplinary team uses a defined protocol to methodically evaluate the significance of deviations from the normal design intention.

The Hazard and Operability (HAZOP) Analysis technique is based on the principle that several experts with different backgrounds can interact in a creative, systematic fashion and identify more problems when working together, than when working separately and combining their results. The HAZOP study focuses on specific points of the process or operation called “study nodes,” process sections, or operating steps. The HAZOP procedure involves taking a full description of the process and systematically questioning every part of it to establish how deviations from the design intent can have a negative effect upon the safe and efficient operation of the plant.