A disaster is typically classified in 2 categories: hazards and threats. Hazards are naturally occurring events, such as blizzards, tornadoes, and flooding. A threat is a human-made event, such a bombing attack or release of a biohazardous agent. Response to an incident must be tailored to the hazard or threat. Whether faced with an earthquake or a hazardous material, incident response must be rapid, effective, and orderly. This chapter focuses on the identification, management, and response to hazardous materials incidents.
According to the US Department of Transportation, a hazardous material is any item or agent that has the potential to cause harm to humans, animals, or the environment, either by itself or through interaction with other agents.46 These agents can be chemical, radiologic, or biological; moreover, the chemical agents are xenobiotics that can exist in the solid, liquid, or gaseous form.
A hazmat incident can be the result of an unplanned or uncontrolled release of or exposure to a hazardous material. Although there are no specific requirements for an event to be considered a hazardous materials incident, typically, there must be the potential for many people or a large area to be affected. This factor differentiates such an event from the majority of xenobiotic exposures that affect only one person.
In addition, a single event could provide exposure to multiple xenobiotics. Each incident, and the response, is unique, and the response required for chemical, biologic, or radiologic agents might differ substantially. For instance, an event in which a biologic agent is released in a densely populated space, such a concert or sporting event, will likely result in a different response compared with the identical xenobiotic being released in an area with low population density, such as a small town. Emergency managers and health care professionals must consider all possibilities and adjust the incident response based on the specific xenobiotics involved, the route of the exposure, and other variables (eg, time, location, and weather conditions). This chapter discusses the basic principles used for a confined and quickly identifiable hazardous materials incident.
In general, a hazardous materials incident response focuses on the care of patients exposed to xenobiotics in the prehospital setting, prepares for multiple casualties, and emphasizes patient decontamination while at the same time trying to prevent exposure and contamination of first responders and health care professionals.
Every emergency response has the potential to involve hazardous materials, and first responders must always consider this as they approach an incident. For example, an apparently simple motor vehicle crash can release gasoline into the environment, or a train derailment may result in the release of an unknown xenobiotic from a transport container. In the prehospital setting, early identification of a hazardous material event can be difficult, but it is vital to collect as much information as possible to achieve an adequate and efficient response.