Control Of Major Accident Hazards 

COMAHControl Of Major Accident Hazards – regulations are aimed at ensuring that businesses take all the necessary measures to prevent major accidents involving dangerous substances and that they also limit the consequences to people and the environment as a result of any major accidents that do occur.

COMAH applies mainly to the chemical industry but also to some storage, explosive and nuclear sites. Any industry that has dangerous substances, as identified in the regulations, above a threshold quantity is subject to the regulations. Sites are either classified as top tier or lower tier, depending on the quantities of the substances held. Top tier sites are subject to more onerous requirements than the lower tier sites.

All plant operators have a duty to take all measures necessary to prevent major accidents and to limit their consequences to people and the environment. Inspection/NDT is one of the measures used to meet the requirements of COMAH.

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