Essential Elements of Process Hazard Analysis

DOE-HDBK-1100-2004

3.0 ESSENTIAL ELEMENTS OF PROCESS HAZARD ANALYSIS

This section addresses topics common to all PrHA methods. A step-wise procedure for conducting a

PrHA according to PSM Rule requirements is presented, followed by recommended approaches for

analyzing scenarios, deciding on action items, and incorporating facility siting and human factors into

the PrHA.

3.1

Step-by-Step Procedure

This section describes the tasks required for compliance with the PSM Rule regardless of the

PrHA method selected. The sequence of these tasks is shown in Figure 3.1. This figure also

indicates where process safety information (PSI) requirements fit into PrHA tasks, and what

documents are generated as a result of each task. Concepts common to all PrHA methods are

also discussed.

To conduct an effective PrHA, both operating management and the PrHA team must understand

their respective responsibilities. In general, the tasks breakdown as follows:

TASK

RESPONSIBILITY

A-F

Operating management

G, H, I

PrHA team

J, K

Operating management and PrHA team

TASK A: LIST PROCESSES THAT ARE COVERED.

Identify all onsite processes having threshold

quantities (TQs) or more of the highly hazardous chemicals (HHCs) listed in the PSM Rule,

29 CFR 1910.119 (Appendix A)3. Be specific about the boundaries of each "process." Assure

that they include all connected vessels and equipment whose upset could result in a release of

HHCs from a location remote from the bulk quantity. The DOE hotline for OSHA questions

and concerns (1-800-292-8061) may help regarding the applicability of the PSM Rule to a given

process or the necessary boundaries of a process.

TASK B: RANK THE PROCESSES BY RISK AND DEVELOP A SCHEDULE OF PrHAS.

If a chemical

facility contains more than one process covered by the PSM Rule, the rule requires that

processes posing the greatest risk to workers be analyzed first. A methodology for ranking is

not specified, but any method chosen must account for (1) the extent of the process hazards;

(2) the number of potentially affected employees; (3) the age of the process; and (4) the

operating history of the process. The following factors should be considered when selecting a

ranking methodology: ease of application, qualitative versus semi-quantitative (order of

magnitude) results, manpower required, and traceability After a prioritized list of processes is

developed, a schedule for PrHAs can be established.

Although not required under the PSM Rule, DOE contractors may want to consider performing PrHAs on

processes using large volumes of hazardous chemicals that do not appear in the Appendix A list. In

addition, contractors may want to consider conducting PrHAs on processes containing/using quantities of

listed HHCs that are just below TQ requirements for coverage under the PSM Rule.