Hazardous substance shall mean any substance or material in a quantity or form, which, in the determination of the fire chief or his authorized designee, poses an unreasonable and eminent risk to the life, health, safety or welfare of persons or property within the city and shall include, but not be limited to, any hazardous substance listed in the National Fire Protection Association Guide on Hazardous Materials or the U.S. Environmental Protection Agency's lists of extremely hazardous substances or the "Florida Substance List" promulgated by the State of Florida Department of Labor and Employment Security.