How do you identify the areas that contribute to the explosion?
The Multi-Energie method

A rigorous approach would first require an atmospheric dispersion calculation to determine the extent of the flammable cloud in order to determine :

• the areas likely to be affected by this cloud;

• their filling level (partial or total).

For example, in the case of the figure "Example of a crossover between a flammable plume and the layout of congested zones", dispersion would identify that zones 1 and 2 are likely to be affected, while zone 3 is not.