Group E (Group E has no Div. 2)
aluminum
magnesium
other metal alloys
Group F
carbon bleck
charcoal
coal
coke
Group G
Flour
grain
starch
Division 1
1. Combustible dust may be in suspension in the air continuously, intermittently, or
periodically; under normal operating conditions; or due to mechanical failure of electric
equipment or protective devices.
Division 2
Combustible dusts not normally present in suspension in the air in explosive quantities
but where accumulation bay be sufficient to interfere with safe heat dissipation from
electric equipment or may be ignited by arcs, sparks, or burning material from electrical
equipment.