HazMat Awareness.

There are many definitions of hazardous materials. The one to know comes from the United States Department of Transportation (DOT). A hazardous material is a substance or material capable of posing an unreasonable risk to health, safety or property when transported in commerce. The term includes hazardous substances, hazardous wastes, marine pollutants, elevated temperature materials, and materials designated as hazardous in the Hazardous Materials Table at 49 CFR 172.101.

The DOT also classifies hazardous materials. A hazard class is a group of hazardous materials that share dangerous characteristics. The DOT has identified nine hazard classes based on the dangers posed in transportation. They are the classes used in the Emergency Response Guidebook (ERG), and the class name alone tells you something about the hazard.

A simpler way to think about it is CBRNE: Chemical, Biological, Radiation, Nuclear and Explosive. CBRNE takes the nine hazard classes and regroups them in a way that is more useful to a first responder, because each component shares a hazard to human life.

These definitions deliberately leave out threats caused directly by human action, such as an active shooter, a suicide bombing or another mass casualty attack. Even so, the response principles in this chapter can often be applied to those events.

The outline sorts chemical hazards into four groups. Toxic or poisonous substances are manmade materials that may cause injury or death to living organisms, and they may be solids, liquids or gasses. Examples include toxic industrial chemicals such as chlorine, acetone, benzene and mercury, agricultural chemicals such as pesticides and ammonia, chemical warfare agents such as nerve agents and vesicants, riot control agents and irritants, and some controlled substances such as fentanyl and cocaine.

Exposure to a toxic substance is either acute or chronic. An acute exposure is a short term, high dose event with harmful consequences. A chronic exposure is a long term, low dose exposure with harmful consequences.

Flammable substances are a high hazard because of ease of ignition, high burning temperature, or difficulty in extinguishment. Examples are gasoline, diesel fuel and alcohol among liquids, propane, butane and hydrogen among gasses, and magnesium, aluminum powder, zinc and sodium among solids. Some flammable solids react violently with water and may self-ignite if they get wet.

Oxidizers do not burn on their own, but in combination with other chemicals they may cause them to burn, or to burn hotter than normal. They can make materials that would not ordinarily catch fire burn readily. Oxygen, hydrogen peroxide and some halogens are examples. Corrosives and acids attack and destroy living tissue such as skin, and some also destroy metals, glass or plastics. Examples are sulfuric, nitric and acetic acid, ammonium hydroxide and sodium hydroxide.

Biological pathogens are naturally occurring living organisms that cause injury or death to other living organisms. A pathogen is a disease-causing organism.

Human pathogens include bacteria, such as anthrax and plague, and viruses, such as smallpox and bird flu. Plant and animal pathogens matter as well, because of their economic significance and the need to avoid spreading them. The outline’s examples are Foot and Mouth Disease, Exotic Newcastle Disease, Classical Swine Fever and boll rot of cotton. Biological toxins, such as ricin and botulinum toxin, are the third group.

Infection control is part of this objective. Professionals must be ready to respond to HAZMAT incidents. Well-designed plans and staff education reduce the probability of incidents and prepare officers to respond appropriately and quickly.