Definition:
A Process Hazard Analysis (PHA) is a structured, formal review to identify hazards associated with industrial processes. Note that this is not a formal IEC term (that term is a Hazard and Risk Assessment (H&RA)). A PHA is used in regulatory space by OSHA and EPA, which are both regulatory bodies in the United States.
Other entities also use it slightly differently. It can be confusing
Methods overview: For how PHA identification methods fit together with risk assessment methods (LOPA, risk graph, FTA, ETA, bowtie) in a complete IEC 61511 H&RA, see Hazard and Risk Analysis Methods.
Go deeper: For a fuller treatment of how “PHA” shifts by jurisdiction, discipline, and scope, see Process Hazard Analysis (PHA): One Term, Many Meanings.
Key Points:
- Required under OSHA PSM and EPA RMP regulations.
- Includes methodologies like HAZOP, What-If, and Checklist.
Example:
A facility calls their risk assessment process a “PHA” in their procedures. It is implemented by doing a HAZOP and a LOPA together. This would meet the requirements of an H&RA under IEC 61511-1. The titling of it as “PHA” is their own preference likely to align it with their compliance department.
See Also: H&RA, PSM, RMP, OSHA, EPA, HAZOP
Cited Source:
- OSHA 29 CFR 1910.119(e).
- EPA 40 CFR 68
- Sphera – What is the Difference Between PHA, HAZOP, & LOPA
- IEC 61511‑1:2016, Clause 8