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C Fires and Explosions
Table C.4 Temperature classes for processing equipment (such as mills, dryers, etc.) based on
the ignition temperature (IEC, 2017)
Ignition temperature of the
critical substance [ ◦ C]
Maximum allowed surface
temperature [ ◦ C]
Temperature class
>450
450
T1
300–450
300
T2
200–300
200
T3
135–200
135
T4
100–135
100
T5
85–100
85
T6