The above link is about US Chemical Safety Board investigations on dust explosions and their recommendations. As I posted earlier on the same subject, I am surprised to know that even iron dust catches fire. Many times we concentrate on the dust that we see in the shop floor. But, airborne dust settled at roof level or on the surface above false ceiling or in the elevated surfaces adjacent to the building from which dust is generated require more attention because persons in these areas are unaware or complacent as they are not the dust generators. Any disturbance due to wind or occasional work in the elevated surfaces or sparks generated from electrical fittings at roof level can be a source of dust explosion. It is said that the dust explosions after the primary explosion are more severe. The dust explosion is identified with a roaring and thunder sound and therefore all shop floor persons should be aware of these symptoms and should run away for safety.
Dust explosions are also possible with grain powder and therefore requires communication of dust explosion hazards to these groups also. Enclosures for dust generating equipment, earthing, flameproof electrical fittings, regular cleaning of equipment and ducts that may contain dust, wet mopping, avoiding synthetic dress and static charge dissipation stations are some of the measures that help in preventing dust explosions.
