Rethinking Terrorism Response Decontamination Issues

Is your jurisdiction ready for a terrorist attack? In a recent report from the September 11 Commission, Vice Chairman Lee Hamilton, a former Congressman from Indiana, said, "We believe that another attack will occur. It's not a question of if. We are not as well-prepared as we should be." While Hamilton was most likely talking about our national preparedness there are numerous areas of our country that have become well-prepared. Through federal grants many communities have accumulated equipment and training to better handle terrorism events. Decontamination (decon) issues have also been at the forefront of preparation efforts. While many of these efforts have been well thought out and conducted with good intentions there are some that argue that the response community needs to rethink what may happen at terrorist events.

In a recent article entitled, "Control the site, then decon? History says no" (1) by Joseph Scanlon, the issue of what may occur at terrorism emergencies is outlined. Scanlon writes that while many agree that in response to terrorist attacks the emergency scene should be managed, decon should be conducted on-scene for all contaminated people, and hospitals should be alerted, it probably won't happen that way. Scanlon shows through numerous case studies, including the Matsumoto and Tokyo sarin attacks in 1994 and 1995, respectfully, that there will be no one site for the emergency, responders enter the emergency picture late, and hospitals will receive victims fairly soon after the event begins. He goes on in the article to ask, "If that's the way things actually happen, why do we persist in planning the way we do?". In order to better prepare for terrorism events and response, Scanlon believes the response community should avoid the idea that chemical or terrorism incidents will occur at just one site or location but may easily spread through secondary contamination. He warns that responders should be aware that the site, or sites, may not be easily controlled, and that decon efforts will most likely not be set-up or operating quick enough to stop contaminated victims from leaving the area. All of the above warnings are based on past incidents, warns Scanlon.

A call to reality is needed! Terrorism attacks will most likely be aimed at large gatherings of people in order to have high impact and receive the notice of the media. Response agencies will most likely be alerted soon after the attack begins but will it be quick enough? Considering the response time, or lead time, and it is readily apparent that first responders will be playing the game of catch-up. It will most likely be impossible to control the scene, the flow of people, and the migration of exposed victims. To ask victims, who may be severely bothered by the acute health effects of a chemical agent, to wait in an orderly manner while decontamination efforts are set-up is laughable. A little empathy is needed here in planning efforts. Stand in the victims shoes for a moment and then answer this question; will you wait to be deconned if your breathing is compromised and your skin is very irritated?

The good intentioned efforts over the past several years may not be enough and they may even be unrealistic. Decon efforts should center around this concept; How can responders do the most good in the shortest period of time? When a terrorist attack has occurred and hundreds to thousands of people have been exposed to lethal agents, responders simply cannot spend time on setting up elaborate decon facilities. The window of opportunity is extremely small in which victims can be saved.

What is needed are systems designed to be fast and quickly employed. At large venues like stadiums, arenas, and music festivals, response agencies should work with facilities to employ fixed decon equipment such as showers. Then, if a terrorist event occurs affected people can be directed toward that area through loud speakers or written message signs (both in English and Spanish). The focus should be to quickly flush contaminants off of as many people as possible, as fast as possible, without worrying about their clothing. Depending on the number of people that may be present at each venue decon rates should exceed the capability of 2,000 people per minute. To achieve this goal, locations such as a large stadium may need numerous decon areas within the building or close to the stands. All ambulatory people should be able to self-deliver to the decon area and first responders can focus on getting non-ambulatory people to be deconned. Mass transit buses can be summoned to the site to transport deconned people away from the facility.

What this is all about is called "emergency decontamination" and by definition is a process that is fast, not very thorough, and not very elaborate. In a recent article (2), Robert Burke stated, "Emergency decon has become a major response objective of first responders to terrorism incidents." Burke goes on to say that every department should be able to conduct effective emergency decon. Emergency decon should be readily employed anywhere, at any time.

What is also needed is the training and equipment for every fire department to employ fast emergency decon. While many departments do have the capability many more do not. This has to be a priority! We need to take care of the first responders first by seeing that this capability is in place across the entire country. In doing so, affected people at terrorism attacks will also be taken care of in the most expedient manner. Nozzles and master streams set on low pressure and wide fog with decon rates greater than 500 people per minute should be the goal of each engine company. Operational time from start to water flow should be less than 1 minute.

Technical decon, by contrast to emergency decon, is more elaborate, more thorough, and slower. This is the type of decon that will be conducted at hospital emergency rooms, by hazardous materials response teams (usually for their own personnel), and in portable decon facilities such as specially designed decon tents or trailers. At large scale terrorism attacks, technical decon should not be the major priority. It may, however, be needed to decon non-ambulatory people and/or responders. By nature, technical decon takes time to set-up and activate and requires numerous responders, in proper personal protective equipment, to staff the effort.

In short, emergency decon is similar to fireground primary searches; it must be completed first and fast! Technical decon is similar to secondary searches; it must be completed second and very thoroughly. These basic concepts are also echoed in a 2003 document from the Soldier and Biological Chemical Command (SBCCOM)-U.S. Department of Defense that is concerned with mass decontamination. In "Guidelines for Cold Weather Mass Decontamination During a Terrorist Chemical Agent Incident" (3) it states "Responders should select the fastest method available because decontamination is most effective when performed immediately. The key to successful decontamination is to use the fastest approach that will cause the least harm and do the most good for the majority of the people." The SBCCOM document aptly summarizes all efforts as "Least harm, Most benefit, Most people".

As Scanlon warns, terrorist attacks will most likely produce expanding sites and contamination will spread as victims leave the area. Indeed, in the sarin attacks in Tokyo of March, 1995, it is estimated that between 5,000 and 6,000 people were exposed to the nerve agent. It is reported that 3,227 presented to 41 hospitals over the first several hours. Many of them were delivered by taxis and buses. Fortunately, the death toll was low in comparison to the potential with nine dead at several sites, one dead upon arrival at a hospital, and two dying a few weeks later from complications. Also, 135 emergency medical personnel suffered symptoms from cross contamination and 33 of them were hospitalized. If those people who were exposed to the sarin were deconned before leaving the area, cross contamination issues may have been minimized. Emergency decon is the key.

Technical decon may also be best employed at the sites where people may flee to. Since it may be impossible to capture all exposed victims and send them through emergency decon, these victims may be deconned at hospitals or medical clinics before they enter and expose staff. Since technical decon efforts take longer to set-up, the time afforded before victims begin to arrive will enable responders to activate their decon tents or trailers. Victims that arrive in the mean time can probably be handled by the emergency room staff in their fixed site decon rooms.

Much of this call to reality centers around capability and resources. This Decontamination Chart (PDF)
is designed to examine and compare the different types of decon, the set-up times, and the decon rates for people. It behooves response agencies to examine where their capabilities lie and prepare accordingly.

While the goal of decontamination efforts is to prevent the spread of contaminants and reduce the effects of chemical and other agents on people, the process is fairly simple. Emergency decon simply uses large amounts of water to flush off contaminants and it can be employed fairly quickly, with easily acquired equipment, and without a large demand for personnel. Technical decon may be best employed at sites where victims may travel to seek medical assistance. It is by nature more thorough and arduous to complete. The whole goal should center around speed of implementation. How can responders do the most good in the shortest period of time?

So, is your jurisdiction ready for a terrorist attack? Hopefully, this article provides some food for thought and empowers you to rethink your decontamination efforts in response to terrorism attacks. Author Scanlon adds: "Experience suggests that the current approach won't work. Surely we can make the necessary changes before it is too late."

As usual, please forward any feedback or input to the author at


  1. "Control the site, then decon? History says no" by Joseph Scanlon, Director, Communications Unit, Carleton University, Ottawa, Canada. Article appeared in Homeland Protection Professional, May 2005, Situation Report Column, pages 8 and 10.
  2. "Emergency and Technical Decontamination for Hazardous Materials and Terrorism" by Robert Burke, Firehouse Magazine, appeared at
  3. Guidelines for Cold Weather Mass Decontamination During a Terrorist Chemical Agent Incident, January 2002, Revision August 1, 2003, by Soldier and Biological Chemical Command-U.S. Department of Defense. Located on-line at National Memorial Institute for the Prevention of Terrorism, MIPT Library, Report #3-PDF document
  4. Appendix V-Swimming Pool Agent Decontamination Data, from Guidelines for Cold Weather Mass Decontamination During a Terrorist Chemical Agent Incident, January 2002, Revision August 1, 2003, by Soldier and Biological Chemical Command-U.S. Department of Defense. (Olympic size pool contains 3,000,000 liters. Up to 1.7 million people may be effectively decontaminated for Agents GB (Sarin) and VX. With a 50% margin of safety factored in 800,000 people could be processed by walking through the pool.)

Related links:

Decontamination Chart
Decontamination Chart