Process Hazard Analysis Methods with Examples

DOE-HDBK-1100-2004

4.0 PROCESS HAZARD ANALYSIS METHODS WITH EXAMPLES

INTRODUCTION.

The PSM Rule allows the use of several PrHA methods. DOE contractors

should select the most appropriate methods for each facility or process and provide the rationale

for their selections. Sometimes a combination of methods may be most appropriate.

The selection of a PrHA method depends on many factors including the size and complexity of

the process and existing knowledge of the process. Has the process been in operation for a long

time with little or no innovation, and has extensive experience been generated with its use? Or

is the process new, or one that has been changed frequently by the inclusion of innovative

features? All PrHA methods are subject to certain limitations. Because PrHAs depend on good

judgment, assumptions made during a PrHA must be documented, understood, and retained for

future PrHAs.

Sections 4.1 through 4.6 below discuss the PrHA methods identified specifically in the PSM

Rule. They are preceded by two example processes (see Figures 4.1 and 4.2) that are referenced

in discussions of methods and used to show a step-by-step approach. Three steps common to all

methods are preparing for the analysis, performing the analysis, and documenting the results.

All the basic information needed about the methods is included in this document, but there are

numerous publications that provide additional information and examples.

4.1

Checklist Analysis

A checklist analysis is used to verify the status of a system. This analysis method is described in

detail in Guidelines for Hazard Evaluation Procedures (CCPS, 1992).

The checklist analysis method is versatile, easy to use and can be applied at any stage in the life

of a process. It is primarily used to indicate compliance with standards and practices. It is also

a cost-effective way to identify common and customarily recognized hazards. Checklists also

provide a common basis for management review of assessments. Many organizations use

standard checklists to control the development of a process or an entire project from initial

design through decommissioning. The completed checklist must be approved by all relevant

staff members and managers before a project can move from one stage to the next.

4.1.1 Description of the Method

A checklist analysis uses a written list of items or procedures to verify the status of a system.

Checklists may vary widely in level of detail, depending on the process being analyzed.

A traditional checklist analysis uses a list of specific items to identify known types of hazards,

design deficiencies, and potential accident scenarios associated with common process equipment

and operations. The method can be used to evaluate materials, equipment, or procedures.

Checklists are most often used to evaluate a specific design with which a company or industry

has a significant amount of experience, but they can also be used at earlier stages of