Designs that lacked inherent safety: case histories

The fundamentals of Inherently Safer Design were not fully appreciated in the initial design (or re-design) in the following series of case histories. Two case histories involving the basic element of plant layout to minimize property damages and injury will be covered first. Simple physical separation could have reduced the losses. A case history that occurred in a bulk chemical terminal tank farm will highlight designs which allowed incompatible chemicals to react, create a fire and a lingering toxic gas release. The combination of these chemicals caused equipment damage in one case and a threat to the public in another case. This paper will conclude with case histories involving poor piping design or poorly identified piping systems, which needlessly resulted in expensive repairs. Exercising the principles of inherent safety would have reduced the severity and perhaps the opportunity of these events. We must employ the techniques of inherent safety to improve our performance.