What are the divisions of Class 3 hazardous materials?
The nine hazard classes are as follows: DOT Hazard Classes Explained It covers compressed gases, liquefied gases, dissolved gases, refrigerated liquefied gases, mixtures of gases and aerosol dispensers/articles containing gas. There are 3 sub-divisions: Division 2.1: Flammable gases. Division 2.2: Non-flammable, non-toxic gases.