Industrial Explosion Risks and How to Protect Against Them
Explosions in industry are rarely caused by exotic materials. Flour, wood dust, metal powders, solvents and fuel gases can all explode when the conditions line up.
What an explosion needs
A fuel (a combustible dust, gas or vapour), oxygen, an ignition source, the right concentration or dispersion of the fuel in air and, for the explosion to build real pressure, confinement, such as inside a silo, duct, filter or room. Remove one of these and the explosion cannot happen.
Prevention
The first line of defence is to avoid explosive atmospheres and control ignition sources: good housekeeping so dust does not accumulate, ventilation, inerting with nitrogen, earthing and bonding against static discharge, certified equipment in hazardous zones, and spark detection in ducts.
Protection
Where an explosion cannot be excluded, protection limits the damage: explosion relief panels that vent the pressure in a safe direction, flameless venting devices, suppression systems that detect and extinguish the flame within milliseconds, and isolation devices such as flame arresters and valves that stop the explosion spreading to other equipment.
Start with a risk assessment
Which measures fit depends on the material, the equipment and the layout. A documented explosion risk assessment, such as the explosion protection document required under ATEX rules in the EU, is the starting point.
Key takeaway
Combine prevention, protection and isolation, and base them on an assessment of your own process.