What Does Explosion Class 3 Mean?
An explosion class 3 is a location in which easily ignitable fibers or flyings may be present in sufficient quantities, either in suspension, intermittently or periodically, to produce ignitable mixtures. These fibers and flyings present a serious fire risk, but not necessarily an explosion hazard. Fibers create layer forms throughout a facility that can cause an ignition, which moves at near explosive speeds.
Safeopedia Explains Explosion Class 3
Examples of fibres that have this ignition potential include: rayon, cotton, sisal or henequen, istle, jute, hemp, moss, and excelsior.
Explosion class 3 locations are further sub-divided in divisions based on the probability of presence of combustible fibers and flyings in the atmosphere. Further divisions define the probability of the presence of ignitable fibers and flyings.
Division 1 - combustible fibers and flyings are present continuously, intermittently, or periodically
Division 2 - combustible fibers and flyings are present only for a short period of time