A. J. KHAN, Contributing Editor, Riyadh, Saudi Arabia
The 2008 Bayer CropScience pesticide waste tank explosion caused by a chemical runaway reaction at the facility in West Virginia (U.S.) resulted in two fatalities and eight injuries.1 The U.S. Chemical Safety Board concluded that although a pre-startup safety review (PSSR) was conducted, it was inadequate—operators and subject matter experts (SMEs) were not involved, and an eight-page checklist was filled with a complete disregard to their details and specifics. Safe work procedures were not updated to reflect process changes and the verification of design vs. as-built was incomplete, resulting in critical valves being missed during construction. The few issues that were highlighted were not properly marked to action parties. These minor and major omissions ultimately coalesced to create the failure of critical barriers, leading to the explosion.
Key indicators of a PSSR program’s success (or failure). Asset owners can determine the health of their PSSR program through:
PSSR CONTEXT
PSSRs are used to confirm that all appropriate elements of process safety management (PSM) have been addressed satisfactorily and that the facility is safe for startup.2 The U.S. Center for Chemical Process Safety (CCPS) presents a vivid analogy: performing an effective PSSR is analogous to checking your math after performing a calculation—or checking your parachute before a jump.2
Regulations. The U.S. Occupational Safety and Health Administration’s (OSHA’s) PSM regulation [29 Code of Federal Regulations (CFR) 1910.1 19] has been followed by the U.S. Environmental Protection Agency’s (EPA’s) risk management program (RMP) rule (40 CFR 68).
PSSR objective. The startup of new or modified equipment is a particularly vulnerable time for safety incidents and other unplanned events that can cause significant financial loss and damage to human life and health. Many elements of good PSM practices and capital project design include measures to reduce the risk of loss on startup. Such losses include, but are not limited to, incidents involving fire, explosion, environmentally damaging spills or gaseous releases, or incidents involving injury to employees or members of the public. A PSSR provides a structured methodology for the safe turnover of ownership from engineering/project managers to operational personnel.2
While smaller changes can be managed through a single PSSR, large and complicated capital projects manage the risk by conducting PSSRs throughout various phases of the project to ensure that all the action items from other design and construction processes are complete. After construction, projects may necessitate a number of PSSRs where different modules of processes and utilities are brought into operation at different stages of commissioning.
PSSR application. Marsh3 recommends the following approach (shown in FIG. 1) for managing various risk assessments throughout a standard project’s lifecycle, comprising hazard identification (HAZID), process hazard analysis (PHA), management of change (MoC) and a final PSSR before the project’s startup.
For larger capital projects (FIG. 2), PSSRs are recommended before commissioning [readiness for commissioning (RFC)], between commissioning and startup [readiness for initial startup (RFISU)], and finally between startup and full handover [readiness for startup (RFSU)].4,5 Organizations can also conduct PSSRs before introducing hazardous utilities/hydrocarbons into a plant to ensure the incremental risks are reduced to as low as reasonably practicable (ALARP).
Major failures. Studies show that industry faces many major PSSR-related issues that lead to incidents, including:6
In addition, experience and literature suggest the following controls to strengthen this critical barrier:
PSSR best practices include:
LITERATURE CITED
AAMISH J. KHAN is an Operational Safety Consultant who has been supporting various renowned companies in the oil and gas, petrochemical and utilities sectors in their safety culture enhancement journeys for two decades. He has a multifaceted exposure to operations leadership, occupational safety, PSM, integrity assurance and audit, enabling him to identify, analyze and treat risk effectively throughout an asset’s lifecycle. He is now involved in co-authoring CCPS safe work practices guidelines with the objective of enhancing the sharing of lessons learned across global industry and softening the safety impact on workers’ lives. Khan is a graduate chemical engineer and holds an MS degree in enterprise risk management from Boston University.