Explosion hazard assessment

In the application of the multienergy concept, a particular vapor cloud explosion hazard is not determined primarily by the fuel-air mixture itself but rather by the environment into which it disperses. The environment constitutes the boundary conditions for the combustion process. If a release of fuel is anticipated somewhere, the explosion hazard assessment can be limited to an investigation of the environment s potential for generating blast. 

The two approaches lead to completely different procedures for vapor cloud explosion hazard assessment. If conventional TNT-equivalency methods are applied, explosive potential is primarily determined by the amount of fuel present in a cloud, whether or not within flammability limits. The cloud center is the potential blast center and is determined by cloud drift. 

The outcome of a vapor cloud explosion hazard assessment can depend greatly on the method chosen, as demonstrated in this subsection with sample calculations. 

Vapor Cloud Explosion Hazard Assessment of a Storage Site... 

The multienergy method applies only if detonation of unconfined parts of a vapor cloud can be ruled out. If so, the explosive potential of a vapor cloud is determined primarily by the blast-generative properties of the environment in which the vapor is released and disperses. Consequently, a vapor cloud explosion can be regarded as a number of subexplosions. Therefore, the first step in applying the multienergy method in vapor cloud explosion hazard assessment is... 

HSE, Explosion Hazard Assessment A Study of the Feasibility and Benefits of Extending Current HSE Methodology to Take Account of Blast Sheltering, Health and Safety Executive report HSL/2001/04, Sheffield, 2001. 

Ministry of Defence, UK, (1988) Explosive hazard assessment, Manual of tests, SCC No.3. 

The first stage of a dust explosion hazard assessment is to determine whether the dust will explode when dispersed as a cloud. The combustibility of a dust can be assessed by conducting an explosion classification test on a representative sample of the dust. In this laboratory test the observation of flame propagation determines whether or not a suspended dust is capable of initiating and sustaining an explosion. It should be... 

VDI Guideline No 2263, dust fires and dust explosions - hazards, assessment, protective measures - explosion protection in fluidized bed dryers, edition 2005-03. 

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