Certifications - Shield Air Solutions, Inc.

Certifications

Third-Party Certifications and Compliances

Classes

According to the National Electrical Code (NEC), there are three types of hazardous locations, Class I, Class II and Class III.

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Divisions

The Division defines the probability of hazardous material being present in an ignitable concentration in the surrounding atmosphere.

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Groups

Nature of Hazardous Substances. The group defines the hazardous material in the surrounding atmosphere.

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Summary

Hazardous locations are classified in three ways by NEC: Class, Division and Group. There are three types of hazardous Classes:

Class I – gas and vapor.
Class II – dust.
Class III – fibers and flyings.

There are two kinds of hazardous Divisions:

Division 1 – hazardous (substance present during normal operation).
Division 2 – hazardous (substance present during abnormal operation)

Finally, there is the nature of the hazardous substance Groups:

Groups A, B, C, and D in Class I locations, and Groups E, F, and G in Class II locations. An example is the classification of a storage area where LP gas is contained in closed tanks. LP gas is a Class I substance (gas or vapor). It’s Division 2 because it would only be in the atmosphere if an accidental rupture or leakage occurred, and it is Group D material.

NFPA496 purge/pressurization of a Control Room allows the use of equipment that is either non-hazardous or has a lower hazloc rating than the environment that it is operating in. An example would be if a non-hazardous device were to be used in a room that would normally be rated Class I, Division 2: our equipment could create and maintain a safe environment in the room for the operation of that device and others like it.

Class	Hazardous Material in Surrounding Atmosphere
Class I	Hazardous because flammable gases or vapors are present in the air in quantities sufficient to produce explosive or ignitable mixtures.
Class II	Hazardous because combustible or conductive dusts are present.
Class III	Hazardous because ignitable fibers or flying’s are present, but not likely to be in suspension in sufficient quantities to produce ignitable mixtures. Typical wood chips, cotton, flax and nylon. Group classifications are not applied to this class.

Division	Presence of Hazardous Material
Division 1	The substance referred to by class is present during normal conditions.
Division 2	The substance referred to by class is present only in abnormal conditions, such as a container failure or system breakdown.

Group	Hazardous Material in Surrounding Atmosphere
Group A	Hydrogen, fuel and combustible process gases containing more than 30% hydrogen by volume or gases of equivalent hazard such as butadiene, ethylene, oxide, propylene oxide and acrolein.
Group B	Hydrogen, fuel and combustible process gases containing more than 30% hydrogen by volume or gases of equivalent hazard such as butadiene, ethylene, oxide, propylene oxide and acrolein.
Group C	Carbon monoxide, ether, hydrogen sulfide, morphline, cyclopropane, ethyl and ethylene or gases of equivalent hazard.
Group D	Gasoline, acetone, ammonia, benzene, butane, cyclopropane, ethanol, hexane, methanol, methane, vinyl chloride, natural gas, naphtha, propane or gases of equivalent hazard.
Group E	Combustible metal dusts, including aluminum, magnesium and their commercial alloys or other combustible dusts whose particle size, abrasiveness and conductivity present similar hazards in connection with electrical equipment.
Group F	Carbonaceous dusts, carbon black, coal black, charcoal, coal or coke dusts that have more than 8% total entrapped volatiles or dusts that have been sensitized by other material so they present an explosion hazard.
Group G	Flour dust, grain dust, flour, starch, sugar, wood, plastic and chemicals.