Double Jeopardy & Process Hazard Analysis

Hey guys, hope you are doing well. Today we are discussing "Double Jeopardy" which creates regular dilemma and stirs up arguments during PHA sessions. If you have participated as a team member or facilitated or scribed in a PHA session, you would be aware of the term "Double Jeopardy". When someone declares, “That’s double jeopardy,” during a PHA, they are definitely not fighting a legal case in court where double jeopardy prevents a person from being tried in court twice for the same offense. Instead, they are arguing that because two things have to go wrong to cause a scenario, the likelihood is so low that it is not credible and there is no need to consider the scenario.

Strategy to define risk reduction measures in PHA

Hope you and your families are keeping safe from COVID. I have been away from writing for some time now as I took up a new professional role in July and had a lot going on. But one of my new year resolutions was to again start writing the blog and share valuable information with you all. Today I am writing about a strategy one can opt for while providing recommendations in a PHA in order to ensure the provision of effective safeguards.

Process Hazard Analysis (PHA) identifies and evaluates hazardous scenarios forming an initiating event - consequence of interest pair. Evaluating a hazardous scenario helps to determine the adequacy of safeguards for a scenario and to establish requirements for improvement of existing safeguards or installation of new safeguards. 

The need for risk reduction measures is defined based on risk assessment usually utilizing predefined risk matrices. Risk reduction measures fall in either of the two categories “Preventative” and “Mitigative”. Preventative is a category that focuses on preventing the hazard while Mitigative is a category that focuses on minimizing the consequences of an event. 

In order to define risk reduction measures, one of the useful strategies is to employ the hierarchy of controls: