Process safety management modifications

Each PSM system can then be examined to determine what system modifications (if any) are needed to address the new issues. For example, the process hazard assessment system might be modified to include participation by industrial hygienists to identify potential sources of exposure. Some process safety management systems (e.g., process documentation) may require no modification to support a wider scope. 

Common sense and the OSHA Process Safety Management standard require a formal method to effectively deal with change in the chemical industry. The safety designed into the original process often occurs after a multidisciplined design team agonized for the optimum arrangement of process and layout. This process safety must not be jeopardized by modification schemes of poor quality. 

Twelve process safety elements have been identified as important in the context of plant design, construction, start-up, operation, maintenance, modification, and decommissioning. This does not include personnel safety, transportation issues, chronic releases to the environment, or community response, which are separate and important issues. Process safety management must deal with each element. Even the best companies, with the best safety records, have room for improvement. 

In consequence of the above-mentioned demand for repeated assessments, when si ficant plant or process changes are made, a rating for minor and major modifications is required, A very carefiil approach for plant modifications was published by the Center of Chemical Process Safety (CCPS) in their series of guidelines for process safety management [9]. In their recommendations, minor changes remain restricted to 100 % replacement in kind or like for like replacements. Any other modifications exceeding those are subject to a safety assessment... 

PSSR (conducted before the modifications are commissioned) is also a part of the MOC procedure. Any new items identified during the PSSR may require further rounds of review and approvals by the reviewers. Completed MOC is an important part of process safety management it needs to be filed in the facility s process safety and project files, and stored for the lifetime of plant operations. These forms are required for future MOC audit and also are useful during future PHA studies. CCPS (1995) and CCPS (2007) presented MOC process and useful check lists. Note that a proper MOC procedure could have avoided the Flixborough incident outlined in Section 3.2 (CCPS, 2007). 

From today s Process Safety Management perspective, we should say a lack of process safety culture prevailed. We should also say human factors and facility siting issues contributed to this incident. The gas-fired heater was originally adjacent to the process with no separation. The accidental heater fire destroyed adjacent process equipment at several levels of the structure. Detailed discussion on the human factors and the facility siting issues are beyond the scope of the one-minute modification... 

The three major OSHA standards most frequently cited to employers regarding contractor safety are Process Safety Management of Highly Hazardous Chemical (29 CFR 1910.110), Control of Hazardous Energy (Lockout/Tagout) (29 CFR 1910.147), and Hazard Communication Standard (29 CFR 1910.1200). These regulations pertain to the hiring of outside contractors and subcontractors to perform repair work, plant modification, equipment maintenance, etc. Many countries around the world have their comparable standards. 

Overall, then, the only additional RMP requirement for plants already covered by the OSHA process safety management regulation is the hazard assessment (including offsite consequence analyses of worst-case and non-worst-case accidental release scenarios). This hazard assessment must not be confused with the process hazard analysis (PHA). The hazard assessment is a study of what will happen in the event of an accidental release and usually includes, for exanple, air dispersion simulations. The PHA (e.g., HAZOP) studies the hazards present in the process and seeks to minimize them through redesign or modifications to operating procedures. 

Each location handling hazardous chemicals must develop, implement, and consistendy use an effective formal method to confidently deal with change. Many vivid examples of flaws in managing change were described in previous chapters. Effective process safety equipment and procedures must not be jeopardized by cavalier workers or poor quality modification schemes. 

The material in this long chapter may not cover the needs of every chemical plant and every petro-chemical plant, but the ten or fifteen Management of Change procedures developed by major corporations and reviewed by me did not seem to exactly fit the needs or culture of my own organization. Trevor Kletz has said many times that improper plant modifications have been a major cause of chemical plant accidents. I have been working in a process safety function for three decades and my experiences have been similar. It just seems appropriate to repeat the first three paragraphs of the second section of this chapter, as a fitting close. 

An identified stated equivalent set of guidelines for process safety is the American Petroleum Institute s Reconunended Practice 7S0. RP750 is intended to assist in the management of process hazards. The objective of the recommended practice is to help prevent the occurrence of, or minimize the consequences of, catastrophic releases of toxic or explosive materials. The practice addresses the management of process hazards in design, construction, start-up, operation, inspection, maintenance, and modification of facilities with the potential for catastrophic release (American Petroleum Institute 1997). 

The insurance loss experience for an organization is closely related to its safety performance. An understanding of how insurance premiums are calculated and the type of impact accidents can have upon premiums can provide the safety manager with an additional method for measuring safety performance. Along with measures of lost workdays and recordable accidents, insurance industry measures should also be part of the safety performance measurement and improvement process. Examples of quantifiable insurance markers that are indicative of safety performance are loss ratios, experience modification rates, and expense ratios. These insurance industry measures are yet another type of performance measure available to the safety professional. 

System safety must be instituted into the facility and product acquisition process (including retrofitting and minor modifications). This section delineates the system safety milestones and safety products in the procurement process. This section should describe how the general procurement process works and how systan safety should be involved in this process. For example, the safety organization should make sure that safety requirements are part of the procurement tendering process and weU defined for bidders and vendors. Poor safety requirements definition has led not just to contract disputes but more importantly has many times led to poor safety management and ultimately to contributing to accidents. 

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