The Art and Science of Process Hazard Analysis for EHS Risk Management
Published On: September 29, 2022
Process Hazard Analysis (PHA) is a powerful tool required for Process Safety Management (PSM) found at 29 Code of Federal Regulations 1910.119 (e). The objective of a PHA is an analysis of hazards following a formalized approach including the team organizational structure. The art and science include selecting the level of detail and methodology for conducting a PHA. The power of PHA can be applied to other Environmental Health & Safety (EHS) situations and to assess risks.
Mitigating EHS risk can be accomplished through use of PHA analytical tools. PHA can be used in complex chemical processes as well as simply selecting an appropriate garage door torsion spring. Another notable use of Hazard Analysis (HA) was to formally minimization risk for fortifying the B-17 Flying Fortress during World War II. Initial analysis focused on returning damaged B-17’s, and it was later discovered the B-17’s not returning should be analyzed to further improve the design. HA and PHA are also elements of Risk Management Plans (RMP’s) found at 40 CFR Part 68 is EPA’s analog for PSM.
A Job Safety Analysis (JSA) is really a simplified PHA completed for short repetitive tasks in facilities. An example could be a performing a JSA for a maintenance activity with possible pinch points.
PHA is the detailed methodologies for addressing processing, hazard analysis and JSA’s. A discussion of PHA follows consistent with PSM and analogs to other programs.
Several methodologies for PHA are specified within the regulation:
Hazard and Operability Study (HAZOP);
Failure Mode and Effects Analysis (FMEA);
Fault Tree Analysis; or
An appropriate equivalent methodology.
Other appropriate methodologies include.
Layer of Protection Analysis;
Fault Tree Analysis; or
These are merely examples of methodologies listed in the regulation as well as other industry-accepted methodologies. The complexity of the process, hazards and other process characteristics help determine the appropriate methodology selected. For example, a HAZOP is the most common methodology and usually a methodology for an anhydrous ammonia refrigeration system. A What-if Checklist is a good methodology for a less complex process. A JSA breaks job functions into manageable parts to evaluate hazard risk.
While this article and its upcoming webinar focus on PSM as the foundation, a Hazard Analysis is a more general name and can be used in many other EHS situations. For example, a wastewater system may present risk of exceeding permit discharge limits so a hazard analysis for, “Why,” permit limits are exceeded can point a facility towards better compliance. The same approach on compliance hazards could be applied to Spill Prevention Control and Countermeasure (SPCC), air permits or hazardous waste management. The necessity and complexity of an RMP HA depends on the Program level. It is important to consider the applicability of PHA in other compliance aspects and the power of using the methodologies to manage safety and environmental risks. A webinar focusing on PHA in the context of PSM will be presented on November 23 along with some cross-over possibilities for managing both safety and environmental risks. Click here to register now.