Westpoort VCA Eindtermen Basis, VOL, VIL VCU Engels

-

An ignition source provides the energy that allows a substance to ignite or explode

- Examples of ignition sources: flames (open fire) and hot gases, mechanical sparks and welding sparks, electrical installations and equipment, hot surfaces, static electricity, lightning Explosion An explosion is a very fast fire with a released pressure wave Influence of fire on the environment Influence of smoke and combustion gases - Limited visibility - Possibly toxic or harmful - The combustion gases are lighter than air Fire heats products in the environment, causing them to reach auto-ignition temperature and spontaneously ignite Radiant heat heats gas bottles and containers in the area to such an extent that they can rupture and explode - The heat makes it difficult to approach the fire - Explosive environments - In an explosive environment it is possible that an explosive mixture may be formed - In this environment, special measures must be taken to prevent the ignition of potentially explosive mixtures - Industries/sectors where explosion risks may be present: chemical industry, landfills, power plants, waste processing companies, gas companies, wood processing industry, agricultural companies (biogas), metal processing companies, food and animal Influence of heat -

Factors required for the occurrence of a fire or explosion - Flammable substance - Ignition energy - Oxygen Concepts related to fire and explosion Flash point (ignition temperature) The lowest temperature at which a liquid develops so much flammable vapor that it can, under normal air conditions, be ignited in the air present. Minimum or maximum amount of gas/vapour in air at which an explosion becomes possible Boundaries of the explosion area Auto-ignition temperature The lowest temperature at which a substance spontaneously ignites without any aid, measured under normal air conditions Explosion area - Mixing ratio between air and a gas/vapour where an explosion can occur - The area between the lower and upper explosion limits Lower explosion limit (explosion limit) - Lower Explosion Limit - The minimum amount of gas/vapour that must be present in air to cause an explosion Upper explosion limit (explosion limit) - Upper explosion limit = "Upper Explosion Limit" - The maximum amount of gas/vapour in the air at which an explosion can still occur - Explosion limits (blast limit) -

Ignition source

VCA (SCC) Final objectives | Page 60 of 66