The Preliminary HAZOP: Advocacy For Use Early-on In the Design Process

The origin and development of the HAZOP was discussed by safety author, Trevor Kletz, at the 2009 Texas A&M MKOPSC Symposium, and Kletz stated the one aspect he would do differently, if he could do it over, would be to add a HAZOP earlier in the design process. The authors refer to this as a preliminary HAZOP or PHAZOP. The risk assessment process is not without limitations and at the end of the risk assessment process the quantification of residual hazards not detected is unknown. The theoretical limit of not knowing what hazards exist is 100% even in the face of the known risks but a practical course of action is determined. The authors’ use career experiences while offering rational pragmatic options for mitigation of risk findings illustrated through case histories referenced to inherently safe design and corrosion and integrity management that has evolved largely over the past 30 years or so. The modes of failure such as degradation of material properties, corrosion, erosion or environmental cracking are critical in deepwater projects due to the cost or impossibility of repairing, retrofitting, or re-habilitation.