Typical Class I Locations: Petroleum Refineries • Gasoline
Storage Areas • Dispensing Areas
• Dry Cleaning Plants • Spray Finishing Areas • Aircraft
Hangers • Fuel Servicing Areas • Utility Gas Plants
Typical Class II Locations: Grain Elevators • Flour and
Feed Mills • Plants that Manufacture, Use or Store Magnesium or
Aluminum Powders • Producers of Starch or Candies • Spice-Grinding
Plants, Sugar Plants and Cocoa Plants • Coal Preparation Plants
and other Carbon Handling or Processing Areas
Typical Class III Locations: Textile Mills • Cotton Gins
• Cotton Seed Mills • Flax Processing Plants • Plants
that Shape, Pulverize or Cut Wood and Create Sawdust or Flyings
Certified for Class I, Division 2, Group D & Class II, Groups
F & G and Class III Hazardous (Classified) Locations
Class I: Hazardous location is one in which flammable gases
or vapors may be present in the air in sufficient quantities to be explosive
or ignitable.
Class II: Are those areas made hazardous by the presence of
combustible dust.
Class III: Are areas where there are easily-ignitable fibers
or flyings present, due to the types of materials being handled, stored,
or processed.
Division 2: Not normally present in an explosive concentration
(but may accidentally exist).
Testing/Certifications Standards:
Electrical Equipment for Use in Class I and Class II,
Division 2 and Class III Hazardous(Classified) Locations. [UL 1604, Third
Edition, October 6, 1995, Including: Bulletins dated 3/22/95 & 5/17/96]
Non-Incendive Electrical Equipment for Use in Class I, Division 2 Hazardous
Locations [CSA C22.2 No. 213-M1987] Electrical Fans [UL-507, Ninth Edition,
9/24/01 and Fans and Ventilators [CSA C22.2 No. 113-M1989. Sixth Edition]
