What is Class 1, Division 2, Classification

Stand-alone Solar Electrical Installations in
Hazardous Locations ….
What is the Class 1, Division 2 Classification?
Page 2
8 Pheasant Run | Newtown, PA 18940 USA | www.morningstarcorp.com | [e-mail]
Hazardous Materials
Class / Division System
Zone System
(1)
Gasses or Vapors
(1)
Class 1, Division 1
Class 1, Division 2
Zone 0, Zone 1
Zone 2
Combustible Dusts
(2)
Class 2, Division 1
Class 2, Division 2
Zone 20, Zone 21
Zone 22
Fibers or Flyings
Class 3, Division 1
Class 3, Division 2
No Equivalent
(1) The United States & Canada have adopted Zones for Gasses and Vapors.
(2) Zones for Dust are not yet developed for North America.
For the purposes of this special feature, we will highlight the North American Class 1, Division 2
classification system and why the charge controllers used in these stand-alone solar powered industrial
electrical systems must be appropriately certified:
 Class considers the industrial ecosystem where flammable or explosive gases/ vapors, liquids or
fibers/dusts may be present:
Class 1
Locations are made hazardous by the presence of flammable gases, liquids or vapors.
Class 2
Locations are described as hazardous because of the presence of combustible dusts.
Class 3
Locations contain easily ignitable fibers or flyings.
 Division refers to the likelihood that ignitable concentrations of flammable materials are present:
Division 1
Designates an environment where ignitable concentrations of flammable gases,
liquids, vapors or dusts can exist some of the time, or all of the time, under normal
operating conditions or where easily ignitable fibers and flyings are manufactured,
handled or used.
Division 2
An environment where ignitable concentrations are not likely to exist under normal
operating conditions or where Class 3 materials are stored or handled.
 Hazardous classes are further defined by Groups. Combustible materials are grouped by their
relevant physical properties. In fact, the Class 1 classification is divided into 4 Groups, determined
by the specific gas or vapor involved—Groups A thru D (these groups include, but are not limited
to):
Group A
Acetylene
Group B
Hydrogen
Group C
Ethylene & Carbon Monoxide
Group D
Propane, Gasoline, Naphtha, Benzene, Butane, Ethyl Alcohol, Acetone & Methane