Chapter 35 Thomas Blackwell, Kenneth Brennan, Craig DeAtley, and Allen Yee The potential for hazardous materials (hazmat) incidents is significant. More than 60,000 chemicals are produced annually in the United States. More than 4 billion tons of chemicals are transported yearly via surface, air, or water routes, with more than 500,000 shipments of hazardous materials made every day. In an attempt to define the magnitude of the nation’s hazmat incidents, the Agency for Toxic Substances Disease Registry (ATSDR) developed the Hazardous Substances Emergency Events Surveillance (HSEES) system in 1990. Fifteen state health departments participate in the reporting system. In these 15 states, the system has shown the following [1]. Whether from household agents, industrial incidents, or acts of terrorism, EMS, fire, and law enforcement personnel face a variety of response issues related to hazardous materials. Every organization that has the responsibility to respond to hazmat incidents should develop standard operating guidelines (SOGs) that delineate roles, responsibilities, and pertinent response procedures. Ideally, responding agencies should coordinate their plans with neighboring jurisdictions to ensure interoperability. SOGs should address when and how to implement personal protective equipment (PPE) use, medical decontamination of ill or injured victims, and technical and emergency decontamination of responders. Individual agency SOGs should be part of a community response plan that provides the foundation for the overall incident response. Of particular importance from a medical perspective is the need for clarity on which agency (or agencies) will be providing medical support in the various work locations (hot, warm, and cold zones) and ensuring that they have the necessary protocols, equipment, and training to carry out their assignments successfully [2]. This level of planning requires that representatives from the various agencies meet on a regular basis to write, train, exercise, and revise the plan. Once a plan is developed, training sessions and exercises should be conducted on a regular basis. All first responder agencies have multiple responsibilities that require ongoing training. Effective training is best conducted by expert personnel who create a rigorous training program for all aspects of response to these types of incidents. Individual agency training can provide important instruction on department SOGs. However, multiagency training conducted on a regular basis permits practice in the areas of unified command, integration of community resources, resource sharing, joint decision making, and information sharing. Effective training culminates with after-action discussions and reports, and revising plans, policies, and procedures. Hazardous materials are found in homes, businesses, industries, and transportation corridors. A comprehensive hazard vulnerability analysis should be conducted to determine what significant risks exist in the local community. The federal Superfund Amendments and Reauthorization Act became law in 1986. Title III of these SARA provisions is also known as the Emergency Planning and Community Right-to-Know Act (EPCRA). SARA Title III requires states to: Specifically, this has required the establishment of state emergency response commissions and local emergency planning committees. The nationwide regulated community of manufacturers and non-manufacturers of hazardous chemicals must report concerning their emergency chemical releases; their Material Safety Data Sheets (MSDS); their facility hazardous chemical inventories (Tier I and Tier II reports); and their toxic chemical releases to the air, land, or water (Toxics Release Inventory). Because of this activity, businesses have reassessed their chemical inventories and their manufacturing processes. In addition, more businesses are working cooperatively with local governments to plan for and try to prevent accidental chemical releases. Fire department preplans and fire marshal inspection of commercial buildings and transportation centers, along with law enforcement intelligence information on high-risk targets and clandestine drug laboratories, should be considered when identifying response risks. After identification of potential risks, medical response procedures should be developed and published in conjunction with the department’s medical director, emergency management, local medical facilities, and other appropriate community experts such as poison centers. Protocols for specific classes of agents or individual threats should be written and include information on signs and symptoms, personal protective measures required, need for decontamination, and treatment recommendations [3]. Written publications on various agents are available from the Federal Emergency Management Agency (FEMA), Environmental Protection Agency (EPA), Occupational Safety and Health Administration (OSHA), and National Institute for Occupational Safety and Health (NIOSH) as well as non-government publishers. In addition, the American Association for Poison Control Centers offers 24-hour planning and response information assistance and can be reached at 1-800-222-1212. The Chemical Transportation Emergency Center (CHEM-TREC), maintained by the Chemical Manufacturers Association, is another 24-hour resource for obtaining planning information and emergency response information, particularly for chemical releases, and can be reached at 1-800-424-9300. The Agency for Toxic Substances and Disease Registry (ATSDR) offers a 24-hour emergency number for health-related support in hazardous materials emergencies, and can be reached at 1-800-232-4636. Hotline services operated by government agencies such as the EPA and US Army Soldier and Biological Chemical Command (SBCCOM) can be contacted for assistance. There are several government web addresses such as those listed below that provide useful planning and response information. After the events of September 11, 2001 and the anthrax attacks in 2001, increasing numbers of agencies have made various levels of PPE available to their personnel. Regardless of the user’s profession, the correct type of PPE must be used for its intended application. The PPE must be appropriately donned and doffed. Understanding the operational limitations of wearing PPE such as limited dexterity, reduced hearing, and muffled voice is best experienced and surmounted through frequent training. Four levels of protection have been defined for work involving hazardous chemicals. Although these levels originally were intended for work at hazardous waste disposal sites, they have been adopted widely in other situations, such as rescue work. Level A is the highest level of protection (Figure 35.1). It is usually only worn by hazmat personnel and others working in areas of very high concentrations of toxic agents. A Level A ensemble consists of a fully encapsulating chemical-resistant suit, positive-pressure self-contained breathing apparatus (SCBA), double layers of chemical-resistant gloves, and chemical-resistant boots. The Level A ensemble will protect against vapor and splash threats. Most hazmat workers who enter the hot zone require Level A protection. This is very expensive, bulky, and requires specialized training in its use. The typical Level A hazmat suit costs several thousand dollars and must be properly cleaned between uses. Manual dexterity is poor and the suits retain heat. With the physiological stressors and the self-contained air supply, Level A ensembles are limited in the amount of time that they can be worn. Figure 35.1 Level A ensemble. Level B is used when full respiratory protection still is required but dangers to the skin are less. It consists of SCBA and a chemical-resistant suit with resistant gloves and boots (Figure 35.2). There is less vapor protection in a Level B ensemble. Figure 35.2 Level B ensemble. Level C is required when air concentrations are expected to be much lower and less likelihood of skin exposure exists. It consists of a full-face air purification device and a non-encapsulating chemical resistant suit with gloves and boots (Figure 35.3). Hazmat teams usually use Level B or C PPE when performing decontamination. This takes place away from the hot zone and when the amount of chemical present on a patient is significantly less than what exists in the hot zone. Also, quantities of chemicals that might present physical hazards, such as explosions, should not be present on a patient. Figure 35.3 Level C ensemble. Level D protection is used only when no danger of chemical exposure exists. It consists of standard work clothes and no respiratory protection. Structural firefighting clothing protects against extremes of firefighting, especially heat and steam. This attire is most suitable for firefighters and includes full protective clothing (turnout coat, hood, and bunker pants), SCBA, helmet, gloves, and boots. Despite the respiratory protection provided by SCBA, limited chemical protection is provided by structural firefighting clothing, and it is considered level D PPE. Self-contained breathing apparatus provides breathable air in an immediate danger to life and health (IDLH) atmosphere. The term self-contained means that the breathing set is not dependent on a remote supply (e.g. through a long hose). An SCBA typically has three main components: a high-pressure tank, a pressure regulator, and an inhalation connection (mouthpiece, mouth mask or face mask). Self-contained breathing apparatus may fall into two different categories: open circuit and closed circuit. The closed-circuit type filters, supplements, and recirculates exhaled gas. It is used when a longer-duration supply of breathing gas is needed, such as in mine rescue and in long tunnels, and going through passages too narrow for a big open-circuit air cylinder. Open-circuit SCBA are more common. The apparatus is filled with filtered, compressed air, rather than pure oxygen. Typical open-circuit systems have two regulators – a first stage to reduce the pressure of air to allow it to be carried to the mask, and a second stage to reduce it even further to a level just above standard atmospheric pressure. This air is then fed to the mask via either a demand valve (activating only on inhalation) or a continuous positive pressure valve (providing constant airflow to the mask). Supplied-air respirators differ from SCBA in that the air is supplied through a line connected to a source away from the contaminated area. SARs are available in both positive- and negative-pressure models. However, only positive-pressure SARs are recommended for use at hazmat incidents. One major advantage the SAR has over SCBAs is that it allows an individual to work for a longer period. In addition, SARs are less bulky than SCBAs. By necessity, however, a worker must retrace his steps to stay connected to the SAR, and therefore cannot leave the contaminated work area by a different exit. SARs also require the air source to be in close proximity (within 300 feet) to the work area. In addition, personnel using an SAR should carry an immediately operable emergency escape supply of air, usually in the form of a small, compressed air cylinder, for use in case of an emergency. Air-purifying cartridge respirators function by allowing the wearer to inhale air through a canister filled with a special sorbent material that binds chemical vapors. Cartridge respirators are inexpensive, portable, and easy to use and store. However, drawbacks to their general use exist. The type of cartridge used must match the chemical vapor in question. Different cartridges must be used to protect from organic vapors, acid gases, chlorine, ammonia, and methylamine. The sorbent materials also have a breakthrough phenomenon, in which chemicals elude off the sorbent after a period of use and then expose the user. Multisorbent cartridges are available that do not require matching with the vapor in question. In general, these have a shorter breakthrough period. These factors limit cartridge respirators to short-term use and to low concentrations of chemicals in the air. This is the situation that exists when patients require decontamination. Cartridge respirators depend on an airtight seal against the face. They require a good fit and cannot be used with facial hair. A moderate amount of work is involved when inhaling across the pressure resistance of the cartridge. All of this requires that any individual using this type of respirator be fitted properly and trained in its use. Cartridge respirators are very versatile for short-term use. They require adequate training of all personnel who may be expected to use them and require someone available at all times to decide which type of cartridge to use. Cartridge respirators are ideal for performing decontamination outside the ED. To overcome many of the problems with air-purifying cartridge respirators, battery-operated versions were developed. These use a battery-operated pump to draw air across the sorbent cartridge and pump it into a hood that surrounds the user’s head. They do not require an airtight fit and can be used with facial hair. They do not require the user to work to draw air across the cartridge and, thus, are much cooler and less anxiety provoking. They also require less individual training. They still depend upon the cartridge to remove the vapor in question; thus, the cartridge must match the vapor. The time of use must be limited because of both chemical breakthrough in the cartridge and battery life. Since a clear shield surrounds the face, they provide better eye contact with the victims. In addition to the PPE described above, a number of accessories and attachments may be worn by public safety personnel including cooling and ventilation devices, flash garments, head protection, Nomex suits, and splash aprons. To address body heat concerns, cooling and ventilation devices can be worn under the PPE and against the body. Because of safety and effectiveness concerns, the use of these devices is not widespread. Most chemical protective suits are not flame resistant and should not be worn in situations where there is a risk of fire. Chemical protective suits can be worn with a flash overgarment. The overgarment only provides limited protection against a flash fire. Helmets can be worn when personnel are operating in situations with overhead dangers from pipes, tree limbs, and similar dangers. These products can be added to PPE to provide additional protection during operations.
Medical support for hazardous materials response
Introduction
Developing standard operating procedures
Identifying potential threats
Medical response planning
Personal protective equipment
Levels of protection for work involving hazardous materials
Available types of respiratory protection
Self-contained breathing apparatus
Supplied-air respirators (SARs)
Cartridge respirators and supplied air respirators
Accompanying accessories and attachments
Implications of PPE use
Physical Limitations
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