Lessons from past process safety incidents

First, the importance of learning lessons from past process safety incidents is highlighted in Section 3.2. The subsequent section presents preliminary hazard review procedure, risk matrix, what-if method, plot plan and layout review, pressure relief system review and fire safety design aspects. Section 3.4 presents PHA techniques and procedures hazards and operability analysis (HAZOP), failure modes and effects analysis (FMEA), instrumented protective system (IPS) design, fault trees, event trees, layer of protection analysis (LOPA) and finally SIS life eyele. The importanee of revision of PSI is highlighted in Seetion 3.5. 

Lessons from Past Process Safety Incidents... 

Sharing of past major incidents with other oil and gas industries provides useful input data for similar process industries in order to identify the most critical barriers and improve their safety processes. One poignant example highlights this matter. In 1998 there was an accident in the gas compression stage of a Middle East oil and gas plant which caused 7 dead as a result of fuel accumulation and vapor cloud explosion which was very similar to the Texas City Refinery disaster on March 23, 2005 in which a distillation tower was overfilled and an uncontrolled release of hydrocarbons led to a major explosion and fires. Fifteen people were killed and 180 were injured in the worst disaster in the United States in a decade. In both incidents, excess hydrocarbons were diverted into a pressure relief system that included a blowdown stack. In the Iranian case, it was equipped with a flare, but one which the operator didn t ignite in Texas City the blowdown stack was not equipped with a flare to burn off hydrocarbons as they were released. As a result, the flammable overflow from the tower entered the atmosphere. Ignition of the escaped hydrocarbons was enabled by startup of a nearby vehicle resulted in the explosion and subsequent fires (Hopkins, 2008). This example shows the repetitive patterns of accidents, and root causes of events all over the world in this sector. The lesson of this paper is that accidents in one country, where the scenarios are very similar, can and should serve as lessons to prevent the same scenario being actualized in other countries. 

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