Facility Siting (CMA/API RP-752)

Nowhere under RMP/PSM is there greater potential to misallocate significant financial resources than in the management of Facility Siting. While most facilities have the "potential" for major events, such as explosions, fires, or toxic releases that could seriously affect the occupants of facility buildings, a risk perspective is essential in determining where and what change is warranted.

Without risk perspective, the danger is that resources are directed at high-consequence hypothetical events, and not necessarily at the high-risk events. Risk-informed decision making takes into account both severity of consequence and likelihood of occurrence in determining whether measures should be taken to address hypothetical accidental scenarios.

Risk-based analysis also provides the means to

assess which risk management options have the greatest risk-reduction efficacy (and these are not necessarily the most expensive options)
determine the balance between accident prevention and accident mitigation planning, and
perform cost-benefit analysis of risk-reduction alternatives.

Unwin Company has diverse experience and in-depth technical expertise in facility siting. We have developed streamlined methods, consistent with API Recommended Practices 752 and 753, that have been used by clients to support their risk-informed decision-making.
Our methods are based on use of an analytical template that facilitates systematic evaluation of explosion sources and toxic/flammable release sources relative to vulnerable facility structures. This template has been encoded as an Excel-based analysis tool. Factors addressed in the template include

Location/size distribution of release sources at the site
Operational events that could result in releases or vessel challenges
Vapor migration characteristics
Relief system and other safety system design bases
Phenomenology of:
vapor cloud explosions (VCEs)
boiling liquid expanding vapor explosions (BLEVEs)
pressure vessel explosions (PVEs)
Potential for operator intervention
Site distribution of structures/buildings
Building structural characteristics.

Our analysis system facilitates expeditious analysis of facility siting per RP-752 specifications, while incorporating a comprehensive consideration of the technical factors governing facility siting risk.