Process safety is an interdisciplinary engineering domain focusing on the study, prevention, and management of large-scale fires, explosions and chemical accidents (such as toxic gas clouds) in process plants or other facilities dealing with hazardous materials, such as refineries and oil and gas (onshore and offshore) production installations.
Thus, process safety is generally concerned with the prevention of, control of, mitigation of and recovery from unintentional hazardous materials releases that can have a serious effect to people (onsite and offsite), plant and/or the environment.
Such events can cause toxic effects, fire or explosion and could ultimately result in serious injuries, property damage, lost production, and environmental impact.
While both domains deal with dangerous conditions and hazardous events occurring at work sites and/or while carrying out one's job duties, they differ at several levels.
A major accident is usually defined as an event causing multiple fatalities, extensive environmental impact, and/or significant financial consequences.
The consequences of major accidents, while typically limited to the work site, can overcome the plant or installation boundaries, thus causing significant offsite impact.
Although they may result in far higher impact to people, assets and the environment, process safety accidents are significantly less frequent than OSH events, with the latter account for the majority of workplace fatalities.
Inadequate isolation, overflow, runaway or unplanned chemical reaction, defective equipment, human error, procedural violation, inadequate procedures, blockage, corrosion, degradation of material properties, excessive mechanical stress, fatigue, vibration, overpressure, and incorrect installation are the usual proximate causes for such loss of containment.
Under particular conditions, such as local congestion (e.g., arising from structures and piping in the area where the release occurred or the flammable gas cloud migrated), the flame front of a flammable gas cloud can accelerate and transition to an explosion, which can cause overpressure damage to nearby equipment and structures and harm to people.
), thus becoming a relatively interdisciplinary engineering domain, although at its core it remains strongly connected with the understanding of industrial process chemical technology.
[13] In 1985, AIChE established the Center for Chemical Process Safety (CCPS), partly in response to the Bhopal tragedy occurred the previous year.
Other equivalent models and regulations have become available since, notably by the EPA,[20] the Center for Chemical Process Safety (CCPS),[21] and the UK's Energy Institute.