by Ron Nichols & Dave Grattan P.E., CFSE
Introduction to Using RAGAGEP for Overpressure Risk Mitigation :
Process Hazard Analysis (PHA) is a key tool used by the chemical, oil, and gas industries to assist companies in identifying, implementing and managing the critical safeguards needed to achieve their risk tolerance criteria. The Process Hazard analysis for some sites may be regulatory driven (e.g., Occupational, Health and Safety Administration’s (OSHA’s) 29 CFR 1910.119 Process Safety Management of Highly Hazardous Chemicals (PSM), or the United States Environmental Protection Agency’s (USEPA’s) 40 CFR 68 Chemical Accident Prevention Provisions (RMP)).
During the PHA the team identifies consequences of concern arising from potential process deviations, identifies existing safeguards, or if LOPA (Layer of Protection Analysis) is required, the Independent Protection Layers (IPLs) available to reduce the likelihood of the consequence to a tolerable risk level. If the team identifies a gap between the potential event likelihood, severity and the minimum target set by the company, the team will propose recommendations to close the gap.
An overpressure scenario can be a significant contributor to the risk of a facility. Overpressure of pressure vessels, piping, and other equipment can result in loss of containment of flammable or toxic materials. This paper will develop guidance including related RAGAGEP (Recognized and Generally Accepted Good Engineering Practice) to help engineers and designers participate in the safety lifecycle for managing the risk of overpressure.