Chemical Industry Garments adapted for First-Responders.

Researchers are discovering that protective garments designed to keep industrial-chemical workers safe in the workplace, also can protect local first-responders--firefighters, emergency medical teams and law enforcement personnel--in cases of hazardous-material spills or terrorist attacks with nuclear, biological, chemical (NBC) or conventional weapons.

"For industry, protective garments are the last line of defense," said Jim Zeigler, a research associate with Dupont's Nonwovens products division in Richmond, Va. "In the event of an NBC incident, they would be the first line of defense for the first-responder."

Materials for protective garments are made at Dupont's Richmond plant, which is located on an old, 500-acre antebellum plantation. Dupont has been manufacturing synthetic materials at this facility since 1929.

Determining the chemical or biological agents involved in an incident and assessing the extent of the damage are factors in selecting the type of protective equipment for first-responders, Zeigler explained.

Emergency teams use a standard procedure called "plume analysis"--based on how far an airborne cloud of chemical gas or contaminate can travel within a specified time frame, while factoring in wind direction and speed--to learn about the nature and scope of the incident, Zeigler told National Defense.

An accident or an attack in an urban setting would be more difficult to monitor and contain than one inside an industrial chemical storage facility or a military arsenal where air-gas-detection monitors measure the toxic level and identify the material involved, officials agreed.

All military depots are equipped with chemical monitors, so workers know what they're getting into if they experience a problem, said a spokesman for the Soldier Biological and Chemical Command. This enables personnel to dress according to the threat, the spokesman said.

To help first-responders select the appropriate level of personal protection, the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA), have issued a multi-level criteria for the protection of emergency workers and citizens impacted by a biological/chemical accident or attack.

Levels of Protection

* Level A, the highest category, deals with encountering a respiratory, eye and skin irritant, found in blistering agents--such as chlorine or ammonia gas-Zeigler explained. Rescue workers would approach the area wearing only Level A suits.

* Level B requires the highest level of respiratory protection, but calls for less attention to skin protection.

* Level C requires the same amount of skin protection as Level B, but permits an easing of respiratory protection. Zeigler said that most military protective gear falls within this category.

* Level D provides for lowered levels of skin protection and generally requires no respirator. This is the usually the final cleanup phase, said Zeigler, after dangerous substances have oxidized--degraded by air and sunlight--or have been dissipated by the wind.

"OSHA recommends that if you don't know what you're dealing with, [always] go with level A, "Ziegler said. "This means workers are totally encapsulated [in their own sealed environment] until identification is obtained."

Before investing in the latest--and perhaps over-sold versions of protective clothing, Zeigler suggested that prospective customers might want to consider factors such as care, application and maintenance of equipment, before selecting protective wear.

All four variables "need to be used in figuring cost," he said, during a presentation at a personal safety symposium, held recently in Washington, D.C.

"When you bring in new protective equipment, you have to consider additional training or even retraining [of personnel]," continued Ziegler. "If money isn't spent [at this stage] on compliance, buying suits and training, consider what the cost is going to be if you don't buy or train."

Besides providing an effective barrier for workers and first-responders, today's protective suits nor only have to be stronger, but mote durable, lightweight, flexible, comfortable and breathable, stated Ziegler.

The old days of rubberized fabric as a "one-size-fits-all" solution, for protective garments, is way in the past, he added.

With a wide array of new uses and chemicals to deal with, Zeigler said, today's suits not only have to be chemical, fire and heat resistant, but also stout enough to prevent cuts, tearing and abrasions, and at the same time, tight enough to repel any particle penetration.

"Heat stress is a ubiquitous problem," when it comes to protective garments, Zeigler said.

With advances in breathable fabrics and improved coolant circulation systems inside the suits, Zeigler said, "it is no longer necessary to sacrifice comfort for improved barrier protection."

Public safety issues tend to become obscured because there are so many sales people our pushing products, Zeigler thinks.

"I don't want to sell something people don't need and then have them not want to look at me again," Zeigler said in an interview. "I'm not interested in pursuing a one-time sell."

According to an FBI analysis of potential terrorism threats, the most common danger still comes from explosives, incendiary devices and firearms, not weapons of mass destruction (WMD).

Other threats, in order of probability are:

* Biological toxins, such as botulism.

* Industrial chemicals, perhaps the easiest to obtain.

* Biological pathogens, such as anthrax.

* Radioisotopes, used in most U.S. medical facilities.

The least probable are chemical and nuclear weapons, which fall into the state-sponsored terrorism category, because of the difficulty in making and storing military weapons-grade materials and developing reliable delivery systems.

Because of a wide variety of toxic substances and unpredictable weather conditions at the site, it is not practical or affordable to have all workers or volunteers fitted for level A suits, said Ziegler.

The greatest need seems to be in Level C, for liquid-proof garments, gloves, boots, and canister respirators, Ziegler maintains.

"Normally, for every Level A suit you have in your inventory," Zeigler estimated, "you will need 20 Level D suits for cleanup that can also be used for modesty garments."

The reason for this precaution is that clothes transport toxicants, he said. During the triage process, victims need to be stripped and placed in Level D suits [coveralls] as soon as possible.

"With a suit made out of Tyvek, [a tough lightweight plastic material made by Dupont] rescue workers can write directly on the material," Zeigler explained. "This way the most important information that hospitals need [name, age, injury, condition] will be right there in front of them."

"Remember, biological incidents don't require a Level A suit," commented Ziegler. "If you think about it, hospitals already do a real good job containing things and providing safety for their workers. Total encapsulation is only necessary when there is a skin and breathing threat combined."

It would be wrong to concentrate strictly on Level A-type hazards and neglect the other levels, he continued. "If you are prepared for level A and nothing else, you are still unprepared, and you've spent a lot of money in the process."

Army STEPO 

The U.S. Army has designed a self-contained toxic environment protective outfit (STEPO) that is rated as a Level A suit. STEPO--made by Chemfab, of Merrimack, N.H.--will not only protect workers while they handle chemical and biological agents, but also missile and rocket fuel, petroleum products such as oils and lubricants and a wide assortment of other industrial chemicals.

"They went out and took the best features of the best available suits and rolled them all into one," comment Bill Haskell, technical programs manager for the National Protection Center. (related story, p.27)

A one-piece suit, STEPO is constructed out of five alternating layers of Nomex and Teflon, both materials made by Dupont. It is a suit that encapsulates the whole body. Employing two separate breathing systems and a personal cooling system, it is fully wired for communications. STEPO was designed to replace the Army's M3 toxicological agents protective (TAP) ensemble that has been in use since the 70s. TAP is made of old fashioned, rubber-coated fabric, which soldiers found hard to decontaminate, because the rubber and chemicals tended to bond.

The Army began fielding STEPO in December 1999. The Army's Explosive Ordnance Disposal Unit is scheduled to receive a total of 3,000 suits, according to a spokesman for Product Manager-Enhanced Soldier Systems at Fort Belvoir, Va. Each unit costs about $4,200, an official said.

Other Army units integrating STEPO into their inventories are the Technical Escort Unit and Army Chemical Activity/Depot personnel.

TAP isn't up to the OSHA/EPA standard, said officials at SBCCOM. The possibility exists that vapors, from the outside, can be drawn into the suit. Even though it is sealed at the cuffs and feet, it isn't completely selfcontained, SBCCOM officials said. The TAP suit has a filtered-air system, which draws air from outside of the suit, they pointed out.

Air Circulation

STEPO uses a circulating air system, said SBCCOM officials. This is called a closed circuit, "rebreather" system that recirculates exhaled air and cycles it through a "scrubber" that removes carbon dioxide. Fresh air is then added from a bottle of compressed oxygen and returned into the user's respirator. The breathing apparatus, which weighs approximately 35 pounds, is worn under the suit. In the self-contained mode, one hour of air is available to the user. Using a tether, for oxygen supply, increases the time a worker can stay in the suit to four hours.

Longer periods of time inside the suit for the user is made possible by what SBCCOM calls a "personal ice cooling system" (PICS). Ice water is circulated through a series of tubes contained in a special shirt worn by the user. The PICS circulator works off a pump unit and a frozen plastic bottle that is attached to the outside of the suit. Water inside the suit, is pumped over the frozen bottle and then returned to the interior. The length of time a worker can stay inside is determined by weather, particularly outside air temperature, as well as by individual stamina.

The TAP system used an "ice vest." The STEPO cooling system is more like air conditioning, as compared to the ice vest, which isn't a circulating-type configuration, officials said.

When it comes to communication, STEPO is wired so users can converse among themselves and with their central command center.

At the present time there are no plans to move STEPO out to civilian rescuers, said an Army spokesman.

To fill this niche, Dupont is producing an encapsulating suit that is currently being used by civilian first-responders. This protective material is called Tychem. It is described by a Dupont spokesman as a thermoplastic barrier film that is laminated to materials such as Tyvek.

Tychem is designed to afford a non-permeable barrier and has been tested against 250 different industrial chemicals and chemical-warfare agents, according to Dupont. Once again, as with other types of suits and materials, there are different grades of Tychem, specifically geared for appropriate response to varying levels of threat. Permeability occurs when a chemical changes state, saturates the barrier (suit) and begins to come through the other side. In tests, the upper level of Tychem has proven to protect users for over eight hours against exposure to the most toxic industrial chemicals and warfare agents.

Suits made from Tychem can cost as much as $700, Dupont said, for a high-range, high-tear resistant polyester suit.

Coveralls and hooded coveralls, made from Tyvek, cost considerably less, and these constitute "the meat of the market," said Zeigler.

Most of the protective clothing, used in a WMD event, will be taken from this lower priced garment, Ziegler said.