SHELTERING CONSIDERATIONS

Positive-pressure filtration systems draw contaminated air into the building through special filters that remove the contaminants. This creates a slight positive pressure in the building, which in turn prevents the nonfiltered, contaminated air from leaking into the building. Experience suggests that such systems, however, are expensive and difficult to properly engineer. A less expensive but less protective measure is to engineer the building controls so that the HVAC system could be completely shut down. Little outside air would be drawn into the structure if all doors and windows were closed.

The ability of an action to adequately protect people in a healthcare facility depends on the characteristics of the toxic agent(s) involved, the size and nature of the release, meteorological conditions, the characteristics of the population affected, and the ability of the threatened structures to provide protection from outdoor agent concentrations. Deciding to shelter-in-place requires a prediction of the outdoor plume concentration of the toxic agent that will occur in the risk area, an estimation of the concentration that will occur inside the buildings at risk, and a calculation of the indoor estimated level of exposure. Deciding to evacuate requires an estimation of how long it will take to move patients and staff out of the building and when they will reach a safe distance compared to the outside concentration that people will experience while evacuating; that is, calculating exposures to those who evacuate in the plume will be considered against exposures to those who have not left (Sorensen, Shumpert, and Vogt 2002).

The indoor concentration of a contaminant is determined by infiltration rates into a building and the inside circulation of air. The inside environment will have a lower peak concentration of a contaminant than the outside air. The lower the air exchange, the lower the peak concentration. Infiltration is measured by air changes per hour (acph) between the outside and the inside or the number of times each hour that an enclosure’s total volume of air is exchanged with outside air. An average air exchange rate for office buildings is estimated to be 0.66 acph and an industrial building to be 0.31 acph with the HVAC system(s) off and doors and windows closed (Engelmann 1990). Little is known about the movement of contaminants inside buildings, especially large and complex structures such as hospitals.

Overall exposure to contaminants in a closed indoor environment will be similar to the overall outdoor exposure because contaminants remain in the building after the plume has passed. If reducing total exposure is the goal, as opposed to reducing peak concentration, then the facility needs to be evacuated or ventilated after the plume has passed or the outdoor concentration is less than the indoor concentration (Rogers et al. 1990).

Sheltering for a biological hazard is slightly different from that for a chemical vapor in that hospital HVAC systems are designed to filter out most aerosols in the size range of biological agents (0.5 to 10 microns) (Weik and Weik 2001). Thus, leaving the HVAC system on would be warranted if the hospital is not under positive pressure.

Sheltering for a radiological hazard is somewhat different from that for chemical hazards in that a building will provide some protection against radiation from inhalation exposure as well as exposure from atmospheric clouds and ground deposition. The amount of protection against radiation is determined by the type of structure and location in the structure. Interior rooms and basements in buildings such as hospitals would typically reduce exposure from a cloud source by 70 percent to 90 percent and from a ground source by 98 percent to 99 percent (Schleien 1983).

DECONTAMINATION

The National Research Council (NRC 1999) defines decontamination as the process of removing or neutralizing a hazard from the environment, property, or life form. However, no consensus nationally or among agencies has been reached on standard operating definitions of decontamination, and existing procedures may contradict best healthcare practices for protecting potentially exposed victims as well as healthcare providers.

For decontamination to be effective, the following three elements must be in place:

1. The contaminants are correctly identified.

2. The procedures and equipment are available and properly employed to neutralize (or remove) the contaminant.

3. The reduction of risk is defensible by scientific or regulatory standards (which is not always possible).

Furthermore, most current decontamination systems are labor intensive and require excessive quantities of water. As Macintyre et al. (2000) note, most decontamination guidelines for treatment of exposed victims were created following military models and are inappropriate in today’s civilian healthcare settings.

This discussion is not intended as an all-inclusive treatment on decontamination dos and don’ts but is meant to alert managers to the potential difficulties and pitfalls in planning procedures for decontaminating victims exposed to hazardous substances.

Types of Decontamination

To protect the healthcare facility, it is important to understand where and how (or if) decontamination is performed outside the medical facility, because the problems associated with decontamination of victims (including secondary contamination) in the ED can often be attributed directly to those factors. The degree to which a patient is decontaminated in the prehospital setting depends on the medical decontamination plan, available resources and medically trained personnel, the weather, and characteristics of the contaminant.

General protocols suggest that patients exposed to a hazardous chemical or biological substance should receive, at a minimum, gross decontamination before transport and treatment. Gross decontamination involves showering clothed patients with copious amounts of water, often conducted by a HAZMAT team with a fire hose or by having victims move through a HAZMAT decon tent or other treatment facility. Patients requiring additional medical attention, antidotes, or other emergency care should receive that care depending on the substance’s effects and the ability of staff to protect themselves during treatment. For some situations, such as a patient exposed to a radiological or nonvolatile chemical substance, use of barrier nursing clothing is ample protection. However, if the chemical is highly volatile or persistent, staff should never attempt care or bring potentially contaminated patients into the hospital without appropriate respiratory protection. This includes admitting patients to ED waiting areas where the possibility of secondary contamination could shut down operations.

Hazardous-materials teams traditionally handle decontamination of the environment and persons exposed to hazardous substances, generally relying on a conservative model that advocates precautionary decontamination of potentially exposed victims. The HAZMAT definition of medical decon or patient decon is what most healthcare providers would consider gross decontamination. The procedures, however, are not much different from those proscribed in hospital settings. The first step is removal and disposal (i.e., bagging and sealing) of patients’ clothing and personal belongings. (Cox [1994] estimates that this simple process removes 70 percent to 80 percent of the contaminant, but little scientific data support that assertion.) Victims are then given a quick overall rinse with water.

Secondary decontamination involves washing rapidly with a decontamination solution—usually a diluted bleach or soap and water—and rinsing again. At this point, victims can be dried, given clean clothes, and sent home or transported to a medical facility. The degree of proficiency will vary depending on equipment, resources, and training. One problem is providing privacy to victims, as not all HAZMAT teams are equipped with individual decontamination units or trailers.

Alternatively, mass decontamination processes victims in one or more groups. Chemical warfare agents can cause large numbers of casualties if dispersed in a vapor or aerosol, as manifested in the sarin incident in the Tokyo subway. Such a situation could also occur in a high-profile event at a stadium, a concert, or an airport. The process requires cordoning off several exits where a decontamination corridor can be set up with fire department aerials and/or deluge guns in close proximity. The nozzles are set at low volume so as not to inflict damage but to maximize the amount of water to which each victim is exposed. Ambulatory victims progress through the deluge so that they may be grossly decontaminated. In conjunction with removal of clothing, this will likely suffice to decontaminate those victims not exhibiting signs or symptoms of chemical agent exposure.

A second method is to set up a sprinkler head near the exit point as a rudimentary decontamination shower. In this scenario, water delivered at 500 gallons per minute will produce 8 gallons per second. If the victim remains in the shower for 3 seconds on average, he or she is exposed to 12 gallons, or the amount used in a normal shower.

In either scenario some clothing is left on, which reduces the effectiveness if vapor has penetrated to the skin. Also at issue is the runoff of wastewater with possible contaminants, the disposal of which must comply with local or state environmental regulations.

Self- and buddy-decontamination techniques can also be employed by first responders, workers in hazardous situations, and groups trained in self-help for emergencies. Such techniques may be needed in situations in which immediate removal of contaminants is essential and no time is available to set up a decontamination operation.

Water temperature is a comfort issue that can affect the time spent showering. Normal fire hydrant water temperature is 55 to 65 degrees Fahrenheit. Discomfort during showering is a particular issue with children and the elderly who may suffer additional distress, especially if the ambient air temperature is much cooler or the weather is windy and cloudy. The outside decontamination process is more traumatic than that conducted in an enclosed environment, especially if victims feel a lack of privacy during the process.

Understanding and Implementing Standards and Guidelines for Emergency Management

Several regulations, guidelines, and standards have improved the management of emergencies and disasters in the United States over the last two decades. Such publications have been developed and released by organizations and government agencies such as ASTM International (formerly the American Society for Testing and Materials), the Occupational Safety and Health Administration (OSHA), the Environmental Protection Agency (EPA), the Joint Commission on Accreditation of Healthcare Organizations (JCAHO), the Department of Veterans Affairs (VA), and the National Fire Protection Association (NFPA).

The principles within these standards and guidelines regarding

• mass-casualty incidents,

• hazardous materials,

• decontamination, and

• emergency management program development.

Multiple- and Mass-Casualty Incident Standards

ASTM standard F-1288, Standard Guide for Planning for and Responding to a Multiple Casualty Incident, covers planning, needs assessment, training, interagency coordination, mutual aid, and other important issues as they relate to multiple-casualty incidents. It identifies key terms and activities and explains how the incident management process is organized at the scene (ASTM 1990).

In addition to that standard, George Washington University recently developed a peer-reviewed model for mass-casualty response that integrates the functional requirements of medical, public health, and emergency management agencies in the Medical and Health Incident Management System (MaHIM) (available online at http://www.gwu.edu/~icdrm/). The model was based on the definition of a mass-casualty incident involving 5,000 casualties, 10 percent of which would be considered significant (Barbera and Macintyre 2002). Casualty refers to any human accessing health or medical services, including mental health services and fatality care, as a result of a hazard impact. The MaHIM model clarifies the types of activities that may become necessary at the community-health-system level and how they would be organized in a mass-casualty incident.

It is a useful tool for jurisdictional and regional system development, education, and planning. The Department of Health and Human Services (U.S. DHHS 2002) and the Department of Homeland Security (U.S. DHS 2003) promote this type of management-system framework and are considering applying MaHIM to support current public health and hospital bioterrorism preparedness (CDC 2003). MaHIM is entirely consistent with broader efforts to create a national incident-management system (The White House 2003).

Hazardous-Materials Legislation

A sentinel event occurred in 1985 in Bhopal, India, in which thousands were killed and injured as a result of the release of a toxic gas from a nearby industrial facility. Congress responded to the concerns of such a disaster occurring in the United States by enacting the Superfund Amendments and Reauthorization Act (SARA) of 1986, amending the Comprehensive Environmental Response, Compensation and Liability Act of 1980.

SARA Title III

The basic purpose of SARA Title III, also known as the Emergency Planning and Community Right-to-Know Act, was to promote emergency planning to respond to chemical releases and to ensure that information regarding chemicals in the community is available to the public and emergency response agencies. These goals are accomplished by

• establishing state emergency response commissions and local emergency planning committees (LEPCs) with responsibility to develop emergency plans to be followed in the event of a chemical release and

• implementing a series of notification and reporting requirements to state and local emergency planning activities with respect to type and quantities of specific chemicals.

Environmental Protection Agency

As part of SARA Title III, the EPA will not enforce HAZWOPER for environmental consequences stemming from necessary and appropriate actions such as decontamination during the phase of an emergency response where an imminent threat to human health and life is present. However, once this phase passes, every attempt should be made to contain the runoff and dispose of it properly (Makris 1999).

Beyond industrial or transportation accidents involving hazardous materials, recent events have directed major emphasis on preparedness for occurrences involving weapons of mass destruction. Because of this threat, hospitals and health departments have become much more involved in communitywide emergency preparedness efforts.

One question that has been hotly debated is how SARA Title III, or more specifically HAZWOPER, applies to healthcare facility preparedness for these types of hazardous materials. OSHAs position until lately had been that if the contaminating substance was unknown, staff performing decontamination at a hospital who were not in the immediate area of the release were required to wear Level B personal protective equipment (PPE), including a mask supplied by an external air source.

Many experts disputed the necessity of this elevated measure of pro tection, contending that Level C PPE using a full face mask with powered or nonpowered canister filtration systems was adequate for hospital decontamination (Macintyre et al. 2000). In September 2002, OSHA took the position that as long as the choice of PPE was based on a risk assessment conducted by the employer, the agency would not require any particular level of PPE and respiratory protection (Fairfax 2002).

Decontamination

Healthcare facilities that do not prepare for the potential arrival of contaminated patients face a dilemma. Refusing to assess and, if necessary, stabilize a contaminated patient is a violation of the Emergency Medical Treatment and Active Labor Act (U.S. GAO 2001). Employees who have not been adequately trained or equipped to deal with the situation can refuse to participate, leaving the facility only one choice: to dial 911 and request support from the local public safety system. These same resources, however, may already be fully involved at the site of the release.

Department of Vetemns Affairs

The VA developed a mass-casualty decontamination program that is based on a site-specific hazards vulnerability and capability analysis of the facility and surrounding community. Permanent or semipermanent showering facilities (in smoking shelters, along an external wall, etc.) are seen as advantageous over temporary tent-type facilities because of the speed of setup and lower expense (VA 2002a). Macintyre et al. (2000) believe that the following aspects are key to an effective decontamination protocol:

1. Event recognition

2. Activation

3. Primary triage

4. Patient registry

5. Collection of clothing and personal property

6. Decontamination

7. Secondary triage

8. Treatment and post-incident activities (e.g., media and family relations, medical surveillance, critique, etc.)

Healthcare-facility-decontamination training programs should follow NFPA standard 473, Standard for Competencies for EMS Personnel Responding to Hazardous Materials Incidents (Beatty 2003). NFPA 473 (this standard may be reviewed at http://www.nfpa.org/PDF/473.pdf?STC=nfpa) identifies the levels of competence required of emergency medical services personnel who respond to hazardous-materials incidents (NFPA 2002a). It specifically covers requirements for basic (Level I) and advanced (Level II) life-support personnel in the prehospital setting. This standard also provides information on training, recommended support resources, medical treatment considerations, patient decontamination, and hazardous-materials characteristics and references.

Emergency Management Standards

Joint Commission on Accreditation of Healthcare Organizations

In January 2001, JCAHO updated its emergency preparedness standards (standards EC.1.4, EC.2.4, and EC.2.9.1^[1.] found in the Environment of Care, or EC, section), adopting the four phases of comprehensive emergency management: mitigation, preparedness, response, and recovery. Other key additions to the emergency management standards were requirements for a hazards vulnerability analysis (HVA), the requirement that healthcare organizations implement an incident command system (ICS) consistent with that used by their community, and the acceptance of tabletop exercises for one of two required annual drills. Specific requirements for drills include the following:

• A facility designated as business occupancy must execute one drill annually.

• Hospitals, long-term-care organizations, ambulatory care facilities, and behavioral health facilities not classified as business occupancy must conduct drills twice a year at least four months, but not more than eight months, apart.

• Facilities offering emergency services or designated as disaster receiving stations must base one exercise on an external disaster, and it must include volunteer/simulated patients who must be triaged, put on stretchers or in wheelchairs, and transported through the system as if they were actual patients.

• An organization must participate in a community drill that is relevant to its priority emergencies and that will assess communications, coordination, and the effectiveness of the organization’s and the community’s command structures.

The events of terrorism that took place in the United States in fall 2001 brought several more changes to the overall 2002 standards, including clarification on the process and products of the HVA (in particular, that procedures should be developed for each priority hazard identified), a requirement for cooperative planning with other healthcare facilities in the geographic area, and procedures for emergency credentialing. In 2003, components of the hospital emergency management standards were extended to long-term care, ambulatory care, behavioral health care, and home health care settings (Environment of Care News 2002). For 2004, the EC standards have been renumbered and reformatted but have not undergone any substantive changes in requirements.

National Fire Protection Association

NFPA emergency management Standard 99, entitled “Healthcare Facilities,” contains very similar requirements to JCAHO (NFPA 2002b). One big difference between the standards is the additional material in the annexes of the NFPA standard: explanatory material, references, and additional planning considerations (NFPA 2002a).

NFPA Standard 1600, Emergency Management and Business Continuity Programs, has gained international recognition and consensus among the public and private sectors. This standard articulates the generic elements of these programs and serves as the basis for an emergency management program evaluation and accreditation system by state, local, and tribal governments (NEMA 2001). Thus, NFPA 1600 represents a standard for communitywide emergency management programs (NFPA 2002c).