Phast and Safeti Explosions extension is able to provide a very quick estimate of potential explosion scenarios and its effects. It is particularly useful for Fire and Explosion Risk Assessments (FERAs) and Quantitative Risk Assessments (QRAs), given the large number of scenarios required to be modelled. It is also useful for general facility siting and building design. EXSIM, on the other hand, provides a more thorough account of physical geometries/obstacles by using computation fluid dynamics (CFD) in the explosion assessment, making it used more for very detailed design work (e.g. layout of equipment within a congested region, blast wall design, structural response/design).

The Explosions extension does not model escalation effects. The Explosions extension can only be used for offshore cases with simple geometry when dispersion can be reasonably predicted by the software and explosion strength can be estimated using GAMES correlation or supplied by the user. Even so, the predicted results of an explosion have no consideration of shielding by blast walls and other obstructions.

The Explosions extension is required to produce impulse information from explosion scenarios. In the process industry, both impulse and overpressure are typically used in building design.