Scope and objective. Here, detail the process scope and limitations as well as the study objectives, such as meeting the requirements of the OSHA PSM regulation or corporate or site process safety standards or goals. Note if this study targets multiple issues such as safety, environmental, business and operability or only safety ones. Describe specific guidelines used to specify consequence levels and likelihood ratings. Explain how safeguard reliability was evaluated. Refer, as appropriate, to process description documentation in the appendices — but specify scope limitations in this section. Consider including a listing of the modes of operation covered, such as startup, shutdown, emergency shutdown, routine operation and non-routine activities. Point out how utilities were considered because they are an important source of common fault causes for process upset scenarios.
Methodology. This section most commonly contains "boiler-plate" text and covers the method(s) used to analyze the process and identify hazards. It typically describes OSHA-approved methods such as checklists, what-if, what-if/checklist, failure mode and effects analysis, and HAZOP. We recommend including some discussion of why the method is applicable to this PHA with supporting references to the PSI. Explain the risk assessment technique applied, including pertinent consequence descriptors and likelihood levels. Detail the risk rankings as well as actions required for each risk ranking, such as action time schedule allowances. Also, list the team participants with their experience and titles here.
Findings and conclusions. Detail all the most important team findings. Action items may include specific follow-up assignments, most commonly for departments, although individuals may be specified. Tracking of follow-up activities will be easier if the number of assigned groups or individuals is kept to a reasonable number such as three or four. Stress the preliminary nature of findings and that the assigned activities will lead to a risk management plan for follow-up and closure. Such a plan may include detailed consequence analysis and release modeling, layers of protection analysis, or quantitative risk analysis. Export tables from the PHA worksheets with the most critical recommendations. Categorize findings by major topic, such as process node, unit operation or recommendation area (maintenance, operations, engineering, etc.). If risk ranking is used, list intolerable level risks with associated action items. What is intolerable will vary from company to company and generally is risk-matrix specific.
Appendices. These should include:
1. All PHA worksheets edited by the PHA leader and scribe and approved by the PHA team.
2. A complete action-item listing with enough detail to allow those responsible for closure to understand each issue and make appropriate responses. Follow the independent reader (six month) rule: "…include enough detail in each recommendation so that you can grasp the issues after a time delay without additional documentation study or conversations with team members."
3. PSI references (include date and version), such as
• equipment files on items within the PHA scope;
• MSDS for all process chemicals and utility materials;
• process flow diagram and written process description;
• standard operating procedures;
• standard operating conditions;
• P&IDs, if applicable to scope;
• process material and energy balances; and
• listing of study "nodes" or other process subdivisions.
In summary, PHA worksheets alone won't suffice. It's critical to have a formal PHA report that allows a reader to easily grasp the important hazards associated with your process and understand the path forward to ensure appropriate risk management. The pointers provided should enable you to develop a report that stands the test of time, revalidation and auditing.
MANAGING THE PROCESS
The resources required to consistently update and effectively manage all the documents and paperwork related to process safety sometimes result in this work falling off the radar screen. Yet, industrial sites handling and processing hazardous materials always must give process safety and, specifically, life safety top priority. Furthermore, an auditor or a jurisdictional agency relies heavily on a review of available documentation and records in evaluating the safety of your facility.
We can't sufficiently stress the importance of having your process safety documentation up-to-date and readily accessible at all times. Even the largest companies often find gaps in their data due to a multitude of reasons from office relocations to staff changes. The sooner you evaluate the current status of your documentation, the earlier you'll be able to address any potential shortcomings.
DAVID E. KAELIN, Senior, is a process safety specialist for Chilworth Global, Princeton, N.J. BRIAN J. KINGSLEY is manager, consulting and training services, at Chilworth Global, Princeton, N.J. E-mail them at firstname.lastname@example.org and email@example.com.