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Weapons of Mass Destruction (WMD)

Human Performance of Military Tasks While Wearing Chemical Protective Clothing


Bernard J. Fine

September 23, 2002


My immediate concern is with the military agenda of this administration, particularly with regard to its eagerness to initiate a war with Iraq. I write as a Senior Scientist (retired) who has spent 37 years at the U. S. Army Natick Laboratories studying the performance of our young men and women soldiers under various kinds of environmental stress. The latter part of my career involved research on the ability of soldiers to performance military tasks while wearing chemical-biological protective clothing in hot and cold environments.

There has been a great deal of press coverage and much hype from Bush, Rumsfeld and associates regarding the necessity of a preemptive attack on Iraq because Hussein possesses nuclear and chemical warfare capabilities, but I have not read one word regarding the potential well-being of young American men and women who will bear the brunt of such an attack. Specifically, I have seen nothing in print about how well our troops are protected against chemical and biological agents. This is particularly important because Rumsfeld has recently stated that ground troops will in all likelihood be used in an invasion of Iraq.

The purpose of this letter is to provide you with a brief overview of the ability of U.S. troops to function in a chemical-biological warfare environment in the hope that it will raise in your mind the advisability of asking certain questions of those in the administration who are so eager to wage war using other people's children. I believe that it is the responsibility of the representatives of the people to apprise the people of the dangers involved in chemical/biological warfare and of what the state of the art is in protecting their soldier-children. Invasion of Iraq may be another pushover because Hussein may not have the weapons we are told he has. On the other hand, if he has them and either uses them or we pursue stupid courses of action such as bombing manufacturing plants or storage facilities with indiscriminate B-52 assaults as in Afghanistan, loss of lives could be extremely high.

Limitations of this report

1. All information in this report is based on unclassified material. As far as I know, classified material that exists pertains to the technical aspects of the protective clothing, i.e., materials used and design, and not to performance of soldiers wearing. the clothing.

2. The report is based on (a) the results of my own research, (b) the published reports of other investigators and (c) discussions I have had with other investigators at various meetings and conferences.

3. The report is based on information available to me through 1997. I make no guarantee that my information base has been all-inclusive. Additional information most likely has been published since my retirement and should be available through military sources.

4. As with any collection of research, quality varies. However, despite the varying quality and precision of some of the research, in my judgment it indicates that there will be significant problems for troops operating. in chemical protective clothing, particularly in hot climates.


The protective clothing ensemble worn by our troops is known as the Mission Oriented Protective Posture (MOPP) and often is referred to as MOPP gear. It provides four levels of increasing chemical (and some biological) protection ranging from slight (MOPP-1) to complete encapsulation (MOPP-IV). MOPP-IV consists of a chemical protective overgarment (suit), hood, gloves, boots and mask with special filter.

Different levels of protection are provided by wearing less than the complete outfit, i.e., no gloves or no boots. This report pertains only to research and field studies in which MOPP-IV was used.


There are two main areas of concern regarding functional efficiency of troops clad in the MOPP-IV configuration of chemical protective clothing:

  1. Limitations imposed by the climate in which the protective clothing is worn, and
  2. Limitations imposed by the design of the clothing itself.

A. Limitations imposed by the climate in which the protective clothing is worn

Of necessity, the protective garment must be impenetrable by outside agents, chemical or biological. Thus, the wearer is enclosed- in an artificial environment that severely limits the evaporation of body sweat and thus reduces the body's ability to maintain normal thermoregulation. Depending on ambient temperatures, humidity, solar load and level of work effort, various degrees of heat stress can result. Even in moderate temperatures, hard physical work combined with high humidity and solar load can generate enough body heat that hyperthermia, heat stress and, ultimately, heat casualties can result.

In high ambient temperatures, the average soldier can do physical work in chemical protective clothing for a few hours or less, depending on the individual. Research has shown that with forced fluid intake and work-rest cycles, work time can be extended. However, in combat, it is difficult if not impossible to instigate work-rest cycles and water intake cannot be guaranteed. Running, with weapon and full field gear, or carrying very heavy loads such as ammunition, for example, under conditions of high ambient temperature, high humidity, and solar load will inevitably result in a very significant number of heat casualties in a short time, possibly one hour or less for some individuals. Research has also shown that after four to five hours performing sedentary tasks (for example, artillery Fire Direction Center duties) in the heat (95F.) at 65% Relative Humidity, performance began to deteriorate markedly, even when troops were given ten-minute breaks every hour and allowed to drink water ad lib. Two of the 20 participants (10%) in the study became heat casualties. In a second study, female soldiers appeared to become heat casualties more frequently and sooner than male soldiers in the same Fire Direction scenario. Only seven of 17 females were able to complete the seven hour scenario. Note that soldiers should be considered to be heat casualties if they cannot perform their duties even though they are still physically able to function. That is, they cannot not contribute effectively to the unit.

In the cold, the primary problem is that fingers undergo rapid and severe cooling (again, depending on ambient temperature). This effect can occur during rest periods while engaged in hard physical work or during actual performance as in the Fire Direction Center Scenario and can reduce the efficiency of performances requiring fine manual dexterity, as in plotting map coordinates or making repairs to weapons, equipment or various instruments. (Note that soldiers would be wearing the chemical protective gloves during these activities.)

Most of Iraq has a continental climate with extremes of heat and cold. The mountainous northern regions have cool summers and cold winters, often accompanied by snow. In central Iraq, the summers are long and hot and the winters short and cool. The mean January temperature in Baghdad is 49F; in July and August it is 92F but temperatures as high as 123E have been recorded. In the southern area around the Persian Gulf some of the highest temperatures in the world have been recorded and humidity is high. Obviously, climate is beyond the control of the military and operations that start in reasonable weather can become disasters if the weather suddenly changes.

I believe, though am not certain, that our armed services are still using a nerve agent antidote composed of atropine paired with pralidoxime chloride (2-PAM) to protect against nerve agent. In most situations, the antidote is supposed to be used by personnel who have been suddenly exposed to chemical/biological agent and are not wearing MOPP-IV. In some situations, however, the antidote could be used by troops wearing MOPP-IV in the heat, for example if their protective outfit is damaged or they prematurely adminster the antidote to themselves because of anxiety or fear and seek extra protection. This is ill advised; laboratory research has shown that atropine/2-PAM significantly shortened endurance time for personnel working in the heat in MOPP-IV.

B. Limitations imposed by the design of the clothing itself

  1. Reduced communication between personnel, both hearing and speaking, due to the mask and hood.
  2. Seriously restricted vision due to the design and optical characteristics of the mask. The field of view is restricted and aiming weapons is more difficult.
  3. Reduced manual dexterity due to constraints imposed by gloves.
  4. Potentially severe visual problems encountered by soldiers wearing contact lenses because they cannot get at their eyes to remove the lenses.
  5. Loss of ability to visually check personnel. Unless names of personnel are displayed on uniforms, no one knows who is who. Difficulty of displaying names so that person can be recognized from all viewpoints is obvious as is the importance in combat of being able to identify all personnel readily.
  6. Difficulty in determining health condition of soldier. His/her face cannot be seen.
  7. Difficulty of performing normal bodily functions is of great importance. There are special facilities designed for persons to be able to relieve themselves while wearing the protective clothing but they are cumbersome and certainly not available to troops engaged in combat. Urinating in the protective garment obviously wets the charcoal lining and can compromise the integrity of the suit. Sweating through the suit, observed in many personnel working in the heat, likewise can compromise the integrity of the suit.
  8. Respiratory stress due to air resistance of mask filters and outlet valves.
  9. Fear of encapsulation or claustrophobia has been reported in some personnel causing them to cease performing, even to extent of ripping off hood and mask.
  10. Feelings of isolation resulting in anxiety, hyperventilation and subsequent fainting have been observed to occur. These occurrences are enhanced by heat exposure.


In my judgment, engaging an enemy who, whether by actual use of or feigned use of chemical or biological agents, forces our military personnel to don chemical protective clothing puts us at a disadvantage so severe as to require a great deal of forethought regarding engaging in such an enterprise in the first place. A worst case scenario can only predict a disaster of major proportions. Wearing chemical protective clothing while under enemy fire in a hot ambient temperature is a stress of the very highest order. It seems to me that before placing our young people in this kind of situation a great deal of thought and consideration must be given to all alternatives short of war that can remedy the situation.

Adequate training is the best means of enhancing performance in MOPP-IV. As in competitive sports, music and many other enterprises, the soldier should be trained in his duties so that he or she can perform them virtually without thinking about the individual components of what he/she is doing. You overtrain, overtrain, overtrain until one performs his/her job automatically. Then you do it in MOPP-IV under normal conditions. Over and over again. Then you do it in the heat! Here the problem becomes a Catch-22. You can't train soldiers in MOPP-IV in the heat to a high enough level of performance without incurring heat casualties among them. In my experience, the army has not been able to solve this problem. Commanders cannot have heat casualties in their troops regardless of whether the troops are in MOPPIV or in their Battle Dress Uniforms. Training in hot climates is adjusted so that heat casualties are not likely to occur. Therefore, most troops have never experienced work at high physical or mental levels in the heat in MOPP-IV and are not prepared for it. Do not let the military tell you otherwise.

I appreciate your reading this submission and hope it has been of service. I note again that my expertise rather expired in 1995 or so but it is my understanding that things have changed very little. The physical equipment has probably improved somewhat, but the problems of operating in the heat will not go away. They will tell you about air conditioned MOPP gear, etc. Yes, they have it for vehicles, but when the equipment stops functioning and you are in your tank in MOPP-IV in the heat, you fry. And they will probably tell you about air conditioned suits for foot soldiers that are computer driven and run by Microsoft software. Anyone who has used Microsoft software in his/her PC and is willing to go into combat with it standing between him/her and death should be signed up immediately or committed to a mental institution.

My intent has been to inform you about an area that not many people know about or even think about. Yet, in the final analysis, it is perhaps one of the most important areas to consider when we are playing dangerous war games without much foundation and are controlled by our emotions rather than by our brains. I've worked with hundreds of our young kids over the past 37 years. Most of them are great people. They are our national treasures. To expend them needlessly in the pursuit of personal goals as I suspect is happening now is obscene.

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