Let’s take another look at both the Temperature Classes
and
the ‘Major” hazardous area classes (Classes I, II and III) so that you don’t confuse them.
Class I & II:
• Class I applies to vapors and gases.
• Class II applies to dust.
Nothing changes with these Classes…these provide ratings for areas, rooms and locations. But the Temperature Class Rating covers the light fixtures that could be used in these locations, as follows:
So – Why is a Temperature Class needed?
For Class I:
The Temperature Classification for a light fixture can’t exceed the ignition temperature of the specific gas or vapor to be encountered in the material Groups listed.
For Class II:
The Temperature Classification for a light fixture must be less than the ignition temperature of the specific dust to be encountered in the Dust Groups listed.
