Abstract
Generally speaking, chemicals are the main source of fire, explosion and toxicity hazards. Notwithstanding technological development, enforcement of ATEX Directives and safety management system application, hazardous releases and following toxic dispersion or explosions in the process sector still claim lives and severe economic losses. Additionally, rather moderate releases of hazardous gases under semi-confined geometry are known to present a serious risk so that there is a need in the assessment of the maximum admissible gas build-up, in connection with adverse effects. For purpose of providing comprehensive warning of the hazardous nature of the considered gas and obtaining a simplified tool, we present a simple unified approach which, starting from the chemical-physical and hazardous properties of the released gas allows estimating both asphyxiation, fire/explosion and toxic exposure hazards.