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Is a hazard review synonymous with a process hazard analysis (PHA)?

The prevention program requirements under 40 CFR Part 68, Subparts C and D, include hazard reviews and process hazard analyses. Is a hazard review synonymous with a process hazard analysis (PHA)?

No. A hazard review is different from a PHA. A hazard review is part of the Program 2 prevention program (40 CFR §68.50). The hazard review must identify the hazards associated with the process and regulated substances, opportunities for equipment malfunctions or human errors, safeguards needed to control the hazards or prevent equipment malfunction or human error, and any steps used or needed to detect or monitor releases. A PHA is a requirement of the Program 3 prevention program (40 CFR §68.67). It involves the rigorous step-by-step examination of processes, process equipment and controls, and procedures to identify each point at which a mishap may occur (e.g., a valve failing, a gauge malfunctioning, human error) and examines the possible consequences of the mishap (58 FR 54196; October 20, 1993). To complete a PHA owners or operators may use a "what if" analysis, a checklist, a hazard and operability study (HAZOP), a failure mode and effects analysis, or a fault tree analysis (40 CFR §68.67(b)).