Which division of hazardous material is considered the most dangerous?

The most dangerous division of hazardous material is Division 1.1, which pertains to explosives that present a mass explosion hazard. This categorization indicates that if these materials are accidentally initiated, they can cause a large and uncontrollable explosion, putting lives and property at significant risk. Division 1.1 materials are highly regulated and require stringent handling and transportation protocols due to their potential for catastrophic consequences.

In contrast, Division 6.1 relates to toxic substances but does not carry the same immediate and widespread risk as Division 1.1 explosives. Division 4.2 includes materials that may spontaneously combust but typically do not pose the same level of danger as high explosives. Division 3.2 encompasses flammable liquids that can ignite and create hazards, but again, the overall risk is not as severe as that presented by Division 1.1 explosives. Thus, Division 1.1 is recognized as the most hazardous due to its potential for mass destruction and its requirements for careful management during transport.