Glossary term
Process Safety Management (PSM)
Subject: Risk Management, Operational and Model Risk
Also known as: PSM
Process safety management is a structured system for controlling the hazards of processes that handle dangerous substances, so as to prevent fires, explosions and toxic releases that can harm many people at once.
Explanation
It focuses on major accidents rather than everyday injuries such as slips or cuts. Typical elements include knowing the hazards of each chemical, keeping up-to-date process information, running hazard studies such as HAZOP, writing operating procedures, training operators, controlling changes to equipment, planned maintenance and inspection, emergency planning, and investigating incidents and near misses. A permit system governs hot work and entry into confined spaces. Several countries make the system mandatory for sites above set chemical quantities, with the United States and the European Union as well known examples. Process safety was reshaped by disasters such as Bhopal, which showed how small lapses in maintenance and alarms could combine into catastrophe. Injury statistics can look excellent right up to the day of a major release, so regulators ask about hazard studies, maintenance backlogs and alarm testing instead.
Example
A refinery runs a hazard study before adding a new storage tank. The team finds that a high-level alarm and an overflow valve rely on the same power supply. It adds a separate supply and a manual checking routine, and updates operator training. A later change request for a larger pump is reviewed in the same way before any work begins.
Not to be confused with
- Occupational health and safety
- Occupational safety deals with everyday workplace injury. Process safety targets rare, large releases from hazardous processes.