1. What is an MMR?

In recent years, the term "safety barrier" has tended to be replaced by "risk management measures" (MMR). circulaire du 10 mai 2010 (circular of May 10, 2010, summarizing the methodological rules applicable to hazard studies, risk reduction at source and technological risk prevention plans (PPRT) for classified facilities, in application of the law of July 30, 2003) defines a barrier as: "A set of technical and/or organizational elements necessary and sufficient to ensure a safety function". This definition introduces the notion of safety function, which is defined by the same circular as: "A function whose purpose is to reduce the probability of occurrence and/or the effects and consequences of an undesired event in a system. The main actions performed by safety...