Today there are many concerns regarding the decontamination of mass-casualty victims. These victims may have been exposed to nuclear, chemical or biological contaminants, or other harmful products. We must prepare ourselves for the task of effectively decontaminating these persons by developing and practicing methods that can be leveraged to safely remove these products from the victims so that they may be triaged, treated and transported to medical facilities.

The first-arriving emergency-response units may be faced with an overwhelming number of victims. The officer in charge will be faced with many decisions upon arrival. Some of the issues that have to be dealt with include decontaminating those that have been contaminated. The decontamination of multiple civilian casualties requires the implementation of effective methods with due consideration of citizen safety, modesty and sensibility. The idea that first-arriving units will simply “open up” on the crowd with a deck gun is wrong and must be dispelled.

The effective and efficient decontamination of exposed persons has been demonstrated to result in fewer and less-severe casualties. Emergency mass decontamination, however, is only one part of a rational decontamination plan. Effective decontamination, which includes protecting exposed persons and providing for the survivability of the emergency healthcare system, cannot rely exclusively on field decontamination of victims at a single place. The concept of “decontamination in depth” entails multiple opportunities for decontaminating patients — implemented in the field, at hospital emergency rooms, at clinics, at trauma centers and at all other patient-collection points.

Decontamination in depth, with field mass-casualty decontamination as a critical centerpiece, is the only system imaginable for dealing effectively with a mass-contamination incident.

This article outlines a practical approach to the issues of field mass decontamination of chemical, biological, radiological, nuclear and explosive casualties. By understanding the basics of contamination and decontamination, the fire officer can make effective decisions regarding why, how, when and where to decontaminate.

Defining Contamination, Decon

There are various types of contaminants to which victims may be exposed. Chemical, biological or nuclear agents, or a combination of these products, may be dispersed in an area by intentional or accidental means. These products may take the form of liquids, gases, solids, or a combination. They can be inhaled, digested or absorbed through the skin. The product then migrates through the victims' systems to the organs.

The products also can be moved from place to place or victim to rescuer, or from victim to victim to provider. This type of contamination is referred to as secondary contamination, or cross contamination. As victims are exposed to the residue of the products, they may carry the products from the area of higher contamination to areas of lower contamination. Those areas can be other persons, places and equipment. The major problem encountered is the difficulty in containing the victims to the area of contamination, especially when the incident occurs in a geographically large area.

Decontamination involves the removal or deactivation of contaminants. The reason for decontamination is very simple. We need to remove products that are harmful from victims before those products can physically harm them. By removing the product(s), we essentially can reduce or eliminate harmful effects to the victim.

When a person is exposed to materials as noted above, they may not necessarily need to be decontaminated. There is a difference between exposure and contamination. Let's use the “puppy accident” model to define the difference between exposure and contamination.

If a puppy has an accident on the sidewalk and you walk up to the pile, the following scenarios are possible:

• If you breathe the fumes you are exposed and will need medical treatment.
• If you step in the pile you are contaminated and will need to be decontaminated prior to medical treatment.

So, with this in mind, we need to be careful regarding whom we decontaminate. We need to look at the incident as it evolves and be specific to victims in our directions. The victims at this point will be scared, confused and disoriented. Many victims will be complaining of many issues as they exit the contaminated area.

How Do We Decontaminate?

There are three methods that can be used to decontaminate victims, responders and responder equipment. We need to look at the incident size, number of victims and available equipment, as well as the expertise that’s available to assist with the type of decontamination to be used. The three basic types of decontamination and their applications are:

Technical decontamination is the same on-scene decontamination of personnel and equipment that we have used throughout almost 15 years of hazmat response. It is set up during pre-entry and becomes the egress and access points to the hot zone. The technical decontamination is to be used for the hazmat team, responders and their equipment. For example, a SWAT team enters a possibly contaminated area. The decontamination procedure for these personnel should address their specialized equipment and, more importantly, their firearms. Guidelines and procedures for handling such situations must be established.

Emergency decontamination is the process of immediately removing contaminants from both victims and emergency-response personnel, foregoing the usual set up of the planned decontamination corridor. This procedure is used to remove as much of the product from the victim(s) in order to afford emergency treatment to protect life. It usually is performed by the first engine company on the scene and uses the flush-strip-flush protocol that is instructed for the operations level. The word “emergency” best reflects the manner in which we must consider mass decontamination. An example of this would be when a SWAT team is used to interdict on a clandestine drug lab. As entry is made, a booby trap releases a chemical into the environment that contacts the entering officers. Additionally, EMS units may be contaminated when assisting the contaminated officers prior to their decontamination.

Mass-casualty decontamination, as stated above, is an emergency. The process of mass decontamination involves the reduction or elimination of contamination through expeditious procedures on a large number of victims. In order to move these multiple victims through a decontamination system, we must consider what needs to be done. Through studies, it has been shown that if we remove the outer layer of clothing, we will remove up to 80% of the contaminant. Once we have removed this clothing, a flushing of the victim with a low-pressure/high-volume shower of water will remove additional amounts of the contaminant. Later, we will discuss the setup and movement of victims through several different mass-decontamination procedures.

There are several methods that can be used to decontaminate victims after exposure to harmful materials. As a first step in the decontamination of mass casualties, responders should not overlook the simple act of removing clothing. As stated above, it is estimated that up to 80% of chemical exposure will be eliminated by clothing removal alone, and removal of clothing can reduce the degree, severity and duration of biological and radiological exposure as well. While complete removal may be necessary under some circumstances, victims should be advised to at least remove all outer clothing (down to uncontaminated undergarments). Victims that decline or refuse to remove clothing should not be physically coerced, but rather should be showered as soon as is practicable and isolated from those that have been fully decontaminated.

It also is critical to remember that the speed at which decontamination is implemented is a significant issue. Minimal decontamination initiated early — and followed by appropriate additional decontamination as capabilities increase — always is preferable to waiting until everything is set up before beginning the process. The key concept here is to separate the victim from the hazard as quickly and as completely as possible. Once the victim is out of the “hot zone,” they immediately should undergo initial decontamination (beginning with clothing removal).

Once this process has been accomplished, there are several methods that can be used to complete the decontamination of victims exposed to harmful materials. These can be broken down in to two areas: wet decontamination and dry decontamination. However for the purposes of this article we will be discussing the more practical approach, which is wet decontamination.

Wet decontamination, as the name implies, involves the use of a liquid to remove contaminants, both wet and dry, from victims and equipment. Water is the liquid that most often is used because it is, of course, readily available. The water is used to dilute, deactivate and physically remove the product from the victim, and is preferable than all other liquid products. The other liquid products that can be used are technical decontamination solutions that should be reserved for use on equipment. The reason for this is that solutions applied to chemicals can produce adverse effects. Those effects can be as simple as an exothermic reaction (emission of heat) to the release of toxic gases, which could be harmful to the victims. Some of the solutions that have been recommended are mixtures of sodium hypochlorite (bleach), isopropyl alcohol, calcium hypochlorite, trisodium phosphate, and mixtures of these products. These solutions should not be discounted for use on equipment, but remember that decontamination solutions should not be used on victims.

Additionally, steam generators can be used to decontaminate apparatus and equipment. However, this method of wet decontamination is time consuming and hard on the equipment.

There are other decontamination considerations, as follows:

Equipment. Some of the solutions mentioned above may be used to decontaminate equipment. Issues that can be addressed prior to the incident are type of PPE (reusable or limited use), monitor protection, disposable supplies, and cleanup/disposal contractors.

Apparatus. Once again, the solutions mentioned above can be used on apparatus, as can steam jets, pressure washing, vacuuming and — depending on the depth of contamination — sandblasting.

Buildings and streets. The decontamination of structures and streets will offer a great challenge to the cleanup contractors. This will take an effort that may involve long-term remediation as well as monitoring. Local, state and federal health officials have to be consulted and will have to maintain a presence until the issues regarding contaminant status are determined.

The environment. Many issues will have to be addressed regarding the environment. The decontamination of water and soil will require the assistance of many local, state and federal agencies that will have to make the determination as to what is clean and when it is clean. The determination of safe levels will be based on the ability to either remove or neutralize the contaminants.

Herding. This issue must be addressed so that the multiple victims who are ambulatory can be decontaminated in an orderly fashion. The first emergency responders on scene must take control of the crowd as quickly as possible. By using firm, clear, concise and authoritative commands, victims can be moved to an assembly area where they can be decontaminated.

Practical Applications

Upon arrival on the scene of an incident where there are multiple casualties and contaminated victims, the responsibility for decontamination will fall upon the first-arriving fire company. These units come with vital tools to handle this type of incident — water, hoses and personnel. This means that it will not be the responsibility of the hazmat response team — rather, it is your job. The hazmat team should assist in the preplanning and training to meet the needs of the engine/truck companies in understanding the concepts of decontamination. However, they will be tasked with duties specific to hazmat mitigation.

When an incident that involves mass casualties occurs, the first-arriving engine/truck company will be faced with victims who have been exposed or contaminated by the byproducts of the incident. It may be as simple as concrete dust, which has hazards of its own, or as complex as multiple chemicals from a dissemination device. These victims, in order to be triaged, treated and transported, must be turned from victims into patients. This process must be done in a safe manner so that it does not endanger your personnel. It also must be performed effectively and expeditiously, so that the casualties can be treated in a timely manner. The effectiveness is important so that all victims who have been involved can be removed safely from the scene and treated.

The first-arriving unit can start the decontamination with what they bring with them. The engine company can deploy nozzles and water to remove the contaminant. This is not a new idea to the fire service. It has been used to decontaminate firefighter protective clothing for years. The use of the booster line or gutter line to wash debris from a firefighter after a fire is common place. We can take the same principals and apply them to the care of multiple contamination victims.

However, there are issues that need to be addressed. One concerns the equipment needed to properly decontaminate multiple contamination victims. The process will evolve based on a locality’s ability to respond. In jurisdictions that have personnel staffing units, there will be a prescribed response to incidents that can be relied upon. In contrast, in communities that rely on non-staffed units, the equipment will come at varying times.

Another issue that must be addressed is the concept of “decontamination in depth.”Local first responders must coordinate their efforts with local hospitals, mutual-aid departments, and other response agencies that may assist in this type of incident.

Perhaps the most important issue that must continually be addressed is that we must act in an expedient manner to remove the contaminated victims’ outer-most clothing and thoroughly rinse them. By following standard operating procedures we, as emergency-services providers, can turn victims into viable patients.

The methods described in this document are guidelines derived from several sources. This is a way, but it’s not the only way. You will need to consider the situation and the available resources. But it is equally important to understand that the decontamination process does not have to wait for the hazmat team to arrive on scene. This is truly a first-responder responsibility.

Glen D. Rudner is a program manager for CRA-USA. He recently retired from the Virginia Department of Emergency Management, where he served as the Northern Virginia regional hazmat officer for 12 years.

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