A substance that poses severe hazards and can react explosively would be classified as which hazard class?

• A. 1
• B. 3
• C. 5
• D. 6

Answer: (A)

A substance that poses severe hazards and can react explosively falls into hazard class 1, which is designated for explosives and explosive materials. This classification includes materials that have the potential to detonate or produce a rapid reaction upon initiation. Such substances are highly regulated due to the extreme risks they can pose to safety, both in transportation and in their use.

Hazard class 1 is further divided into multiple divisions, each representing different types of explosive risks, such as primary explosives that are sensitive to shock, friction, or heat, and secondary explosives that are less sensitive and require an external impact to detonate. This context highlights the critical nature of the materials within this class and the stringent protocols in place to manage them safely.

The other hazard classes mentioned do not encompass explosive substances; for example, hazard class 3 pertains to flammable liquids, class 5 relates to oxidizers and organic peroxides, and class 6 involves toxic and infectious substances. These materials present significant risks, but they do not inherently involve explosive reactions as defined for hazard class 1.