Review of the Process Hazard Analysis

D0E-HDBK-1100-2004

ANALYSIS DOCUMENTATION.

PrHA report documentation should include the PrHA worksheets,

checklists, logic diagrams, human reliability analyses, and any other analysis made to better

understand the scenarios. The PSM Rule requires that human factors that impact scenarios as

cause or protection be expanded to analyze the basic cause of errors or response failures. For

example, a cause may identify that an operator can turn the wrong valve to initiate an accident.

The PSM Rule requires that basic causes also be identified. For example, valve is not labeled;

the operator has not been trained on the operation; or the operator forgot the step. There may be

more than one basic cause. (See also Section 3.2, paragraph on Human Factors.)

PROCESS SAFETY INFORMATION.

This section need not replicate data stored in other locations,

but should provide a list of the drawing numbers, including revision numbers, and other basic

data used in the PrHA. The location of these data should be provided.

5.2

Review of the Process Hazard Analysis

After completion, the PrHA report should be reviewed internally. The review starts with an

assessment of the team and its credentials. A technical review follows, focusing on the

completeness of the analyses and the traceability and understandability of the documentation.

OVERALL APPROACH TO THE PROCESS.

Completeness of a PrHA depends on how methodical

the PrHA team is in its approach. Reviewers should ask the following.

Did the PrHA work its way through the process systematically, or did it "jump

around," overlooking important scenarios. Scenarios are harder to find if the PrHA

does not move methodically from one part of the process to the next.

Were all parts of the system considered? All hardware and procedures should be

considered, from the receipt of hazardous chemicals through their use in the

process. In addition, if process connections exist, material flowing into systems

where it is not designed to be should also be considered.

Were all stages and operating modes of the process considered? Review should

include analysis of procedures for material receipt and unloading, startup, shutdown

(emergency and normal), and transitioning to partial operation (e.g., 100 percent to

500 percent production).

How long did it take to perform the PrHA? Too short a time could indicate lack of

thoroughness. Or the PrHA may have been dominated by one person.

Alternatively, the leader might have prepared the PrHA ahead of time and used the

meetings to confirm his work.

PROCESS DEVIATIONS.

Not all PrHA methods specifically identify process deviations.

However, to review the PrHA scenarios for completeness, a reviewer can use process deviations

such as those listed in Table 5.1, combined with process parameters.