A quantitative methodology for risk assessment of explosive atmospheres according to ATEXDirective.

The Directive 99/92/EC (ATEX 137) deals with the safety and health protection of workers potentially exposed at explosive atmospheres. The application of the ATEX Directive requires the assessment of specific risks due to the presence of potentially explosive atmospheres. The potential development of explosive atmospheres is generally typical of industries classified at major hazard, but it is also possible in other industries where flammable materials are handling. Since the assess of the risk due to the formation of explosive atmospheres is required in both the cases and it is fundamental for the safety in the workplaces, a quantitative approach has been proposed. The objective of the paper is to describe the main aspects of a quantitative methodology based on a probabilistic risk assessment starting from a detailed knowledge of the analyzed system.