OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at http://www.osha.gov.

June 22, 1998

Mr. Baruch A. Fellner
Gibson, Dunn & Crutcher, LLP
1050 Connecticut Avenue, N.W.
Washington, DC 20036-5306

Dear Mr. Fellner:

The following response is in reference to your letter dated April 7, 1997, to me, related to employer requirements under OSHA's (Process Safety Management of Highly Hazardous Chemicals, Explosives and Blasting Agents [PSM]) standard for updating and revalidating process hazard analyses [PHA](29 CFR 1910.119(e)(6)). We apologize for the delay in our response.

You asked that OSHA review a list of procedures to determine if they meet requirements of the 29 CFR 1910.119(e)(6). The subject standard is a performance oriented standard and therefore, it would not be appropriate for OSHA to evaluate your set of specific procedures to determine if they apply to all workplaces covered by the PSM standard. The only requirements OSHA specifies in the subject standard is that the PHA update and revalidation be conducted at least every five years by a team which meets the requirements of 1910.119(e)(4).

Even though OSHA does not specify other requirements for this standard, 1910.119(e)(6), OSHA does require employers to insure that PHAs are current and accurately reflect covered processes. To determine if a PHA can be revalidated and updated, employers must make evaluations of existing PHAs using the specific requirements to be addressed in a PHA as defined in 29 CFR 1910.119(e)(3). After employers evaluate existing PHAs using the 29 CFR 1910.119(e)(3) criteria and have made updates when necessary, then employers may revalidate their respective PHAs as being current and accurate.

Your understanding of OSHA's intent related to the conduct of the PHA update and revalidation process is correct. OSHA does not intend that the requirement to update and revalidate PHAs at least every five years mean that an employer must conduct all new and complete PHAs on processes which have received initial PHAs as required by the standard. To accomplish this employers must establish the scope and extent of their PHA updates and revalidations to include at least the following: evaluations of existing PHAs for accuracy and completeness using the criteria set forth in 1910.119(e)(3); checks to ensure that modifications to processes since the last PHAs have gone through management of change procedures or PHAs when required and that those changes are reflected in the PHAs; an evaluation of process safety information (PSI) to ensure that it is complete, current and accurate; verifications to ensure PHA specified procedures are adequate, up-to-date and are being implemented; determinations that existing PHA recommendations have been documented in their required respective areas such as PSI, PHAs, and procedures (operating, mechanical integrity, emergency response, etc.) and have been implemented; a review of all incident investigation reports required by 1910.119(m) to assure all affected PSI, procedures, training, etc., have been updated to reflect recommendations set forth in the subject reports and that appropriate information from those reports have been incorporated into the PHAs. Finally, OSHA intends that the PHA update and revalidation be documented.

Addressing your PHA revalidation and update procedure, we noted the following:

1)   procedure steps are not included either individually or as a group which address evaluating existing PHA's to assure the criteria of 1910.119(e)(3) are met. Your procedure does address one of these criteria - identification of any previous incident. However, the other specific criteria are not addressed including the hazards of a process, engineering and administrative controls, consequence of failure of engineering and administrative controls, facility siting, human factors, and a qualitative evaluation of the failure of controls;

2)   your procedure step which stated that only piping and instrumentation diagrams (P&IDs) need to be reviewed to ensure that they are up-to-date, is not complete. OSHA requires employers to review all PSI, including P&IDs to ensure that it is complete, current and accurate; and

3)   your procedure step which states that a field check be conducted by operators to assure the accuracy of the existing PHA, is encouraged by OSHA, however, OSHA does not specify individuals or various job classifications e.g. operators, to conduct these field checks.

If you have any questions related to this letter call Mike Marshall at 202-219-8118 ext. 12.


John B. Miles, Jr., Director
Directorate of Compliance Programs Assistance