Hazard study generating deviations

A formal operability study is the systematic study of the design, vessel by vessel, and line by line, using guide words to help generate thought about the way deviations from the intended operating conditions can cause hazardous situations. 

Hazard and Operability Study (HAZOP) a systematic, qualitative technique to identify process hazards and potential operating problems using a series of guide words to generate process deviations. 

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