What does IEC 60079 mean?

IEC 60079 is a series of explosive atmosphere standards that covers a wide array of considerations for component usage in hazardous areas, as well as defining different hazardous area classifications. An important section of the series specifically covers equipment repair, overhaul, reclamation and modification.

How do you classify hazardous areas?

Hazardous locations are categorized by class, group, and division as follows. Class I: Denotes areas where flammable gas, vapor, or liquid is present. Class II: Denotes areas where combustible dust is present. Class III: Denotes areas where ignitable fibers are present.

How do you classify ATEX zones?

The most common values used are:

Zone 0: Explosive atmosphere for more than 1000h/yr.
Zone 1: Explosive atmosphere for more than 10, but less than 1000 h/yr.
Zone 2: Explosive atmosphere for less than 10h/yr, but still sufficiently likely as to require controls over ignition sources.

Which temperature class is better t1 or T6?

A T Class rating of T1 means the maximum surface temperature generated by the instrument at 40° C is 450° C. A rating of T6 means the maximum surface temperature generated by the equipment is 85° C….T Rating Equipment.

Gas Area Classified T Rating	Suitable Equipment
T6	T6

What is a Zone 1 area?

A Zone 1 area is classified as a place in which an explosive atmosphere consisting of a mixture with air or flammable substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally. These are typically process areas where gases are more likely to be present.

What is Zone 1 and what are its specific requirements?

Which temperature class is best?

These surfaces must be kept below 80% of the auto-ignition temperature of the atmosphere. For Group I atmospheres any external surface must be kept below 150°C and any internal surface protected against the entry of coal dust must be below 450°C….Temperature Classifications.

CLASS	SURFACE TEMPERATURE °C
T1	<450
T2	<300
T3	<200
T4	<135