It is the hazard group for spontaneously combustible materials.
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In hazardous materials classification for transportation, Class 2, division 2 (more properly called Division 2.2) is for non-flammable gasses.
Class 2 division 1, more properly called division 2.1, is for flammable gasses.
There is no Class 3 Division 2; Class three has no subdivisions.
Division 4.2 is spontaneously combustible material.
Division 4.2 is spontaneously combustible material.
In the DOT system for classifying hazardous materials in transportation, Class 2, Division 1 (more properly called Division 2.1) is for flammable gases, usually compressed flammable gases.
There are two unrelated hazard classification systems that have categories called "Class 2 Division 2" One is the NFPA system for designating explosive environments. The other is the DOT system for classifying materials that are hazardous in transportation. In the NFPA system for explosive environments, Class 2 locations are hazardous because of the presence of combustible (explosive) dust. Class 2, Division 2 locations are places in which combustible dusts will not normally be in suspension in the air, or will not be likely to be thrown into suspension by the normal operation of equipment or apparatus, in quantities sufficient to produce explosive or ignitable mixtures, but where accumulations of dust may be sufficient to interfere with the safe dissipation of heat from electrical equipment or apparatus, or where accumulations of dust on, in, or in the vicinity of electrical equipment might be ignited by arcs, sparks, or burning material from such equipment In the DOT system for hazardous materials in transportation, Class 2 is for compressed and poisonous gases. Class 2, Division 2 (also called Division 2.2 ) is for non-flammable compressed gases.
Class 6, Division 2 (more properly called Division 6.2) is for infectious agents.
DOT Class 2, Division 1 (more properly called Division 2.1) is for flammable gases.
In the realm of hazardous locations Class 1 refers to an environment containing flammable or explosive vapors or gases and Division 2 is a location where those gases are expected to be present only during an upset condition.
DOT Class 2, Division 1 (more properly called Division 2.1) is for flammable gases.