Hazardous materials are not distinguished as class A or B but by their inherent dangers, like corrosive substances, poisonous gases, and combustible fluids.
The classifications of class A and B are delineated in GB50160-2008 “Petrochemical Enterprises Fire Safety Design Standards.”
Pentane, with a flash point of -40℃ and an explosive lower limit of 1.7%, is categorized as a Class A fire risk hazardous chemical.