To illustrate what's involved in developing appropriate documentation, let's look at a PHA.
Spreadsheet-like worksheets alone don't suffice to meet OSHA PSM requirements for covered processes or good engineering practice for noncovered ones, as detailed by the American Institute of Chemical Engineers' Center for Chemical Process Safety (CCPS).
The PHA is a key part of the overall PSI of a process. Unfortunately, the OSHA PSM regulation doesn't specify the need for or format of a formal PHA report but does require documentation of the effort. In addition, under RAGAGEP (Recognized and Generally Accepted Good Engineering Practices) OSHA may interpret the quality of documentation against the CCPS recommendations.
The OSHA PSM regulation requires a plant to keep the PHA and subsequent revalidations for the life of the process. In addition, the site must document all follow-up activities stemming from PHA recommendations and retain the documentation. These retention practices make sense for non-OSHA processes as well. Such retention is important to the periodic PHA revalidation process and management of process changes to ensure that new un-assessed hazards aren't introduced.
The PHA report must contain a number of elements.
Facility siting. OSHA PSM requires PHA reports to include a description of how facility siting was considered, safety-critical findings and recommendations for follow-up activities. Siting checklists such as those of the CCPS are good tools for siting considerations but the checklists alone may not provide enough detail about findings. It's possible that some highly hazardous materials will require additional efforts such as consequence analysis and risk analysis and their results documented or referenced in the PHA report; we recommend including dedicated paragraphs on these.
OSHA expects a plant to specifically address hazards associated with the location of buildings and employees as well as the discharge from emergency relief equipment. Regardless of hazard assessment method applied, the report must indicate where these hazards exist and how they are managed.
Human factors. Discussion of these is another OSHA-PSM-required element; like facility siting, human factors often are covered by a specific checklist. In addition, a site should specifically consider human factors in the PHA worksheets for process safety hazard scenarios regardless of how a scenario is identified. Consistently use phrases such as "human error of omission" or "human error of commission" throughout the worksheet (in the "cause" column) to demonstrate and document consideration of these human factors for operators, mechanics, engineers, management and others. Also, consider hazard and operability studies (HAZOPs) and job safety analysis to uncover potential hazard scenarios caused by human factors. These studies could be follow-up activities recommended by the initial PHA study.
Numerous references describe formats that should be used for a technical report. The PHA report should follow this general style because it covers a scientific method used to assess process hazards.
The key sections of a PHA report include:
General. The report must have a title page, table of contents and pertinent document-control identifiers specific to site needs.
Executive summary. This section, which generally is limited to one or two pages, provides management with an overview of the report, including scope, methodology, significant findings and the most important recommendations. If the PHA uses risk ranking, this section is used to summarize those discovered scenarios, if any, with the highest risk. The executive summary is where you will find the answers to basic questions of who, what, where, when and how. In most cases, this section is written last.
Introduction. This begins with a description of what the report addresses, including a short process description referencing pertinent detailed PSI such as the operating procedures, process flow diagrams, P&IDs, and MSDS for the process chemicals. It then describes the content to follow.