Classification of flammable dust according to the self-ignition temperature of dusts

Dust	Typical self-ignition temperatures (°C) - Mist	Typical self-ignition temperatures (°C) - Layer
Aluminium	590	> 450
Coal dust	380	225
Flour	490	340
Wheat dust	510	300
Methyl cellulose	420	320
Phenolic resin	530	> 450
Polythene	420	Some grains
PVC	700	> 450
Soot	810	570
Starch	460	435
Sugar	490	460