By Richard M ArndtNovember 20, 2019
Necessity is the mother of invention. When the U.S. Army Chemical, Biological, Radiological and Nuclear (CBRN) School's Joint Experimentation and Analysis Division (JEAD) needed to find a way to get more mileage out of the expensive protective suits worn by Army civil support teams in radiological environments, they looked for answers from what seemed like a peculiar source - a team of biologists in the Utah desert.
But according to Division Chief Brian Bennett of the U.S. Army Combat Capabilities Development Command's (CCDC) Chemical Biological Center's BioTesting Division, it's not as strange as it sounds.
"Our sole function here," he explained, "is to evaluate new technologies and techniques for Soldiers. Our area of expertise here is handling aerosol clouds, because that's how you launch a biological attack. Because radiological fallout consists of aerosolized particles, testing the radiological decontamination techniques fit well within the division's capabilities."
JEAD's Tom Murphy is counting on the BioTesting Division's expertise. "Right now these suits are one-and-done. Given that the suits are hot, and that the work conducted while wearing them is typically strenuous, civil support teams members work/rest cycle requires at least two suits per day per team member."
At $2,000 a pop, the costs add up fast.
So the BioTesting Division was asked by JEAD to devise a test to determine whether the protective suits could be decontaminated and reused, and if so, how many times.
In order to answer this question, the team developed a novel plan that was based on an approach they often use in testing biological aerosols, and tailored it instead to this radiological application. The plan involved simulating the radiological fallout through controlled release in their Aerosol Simulant Exposure Chamber of a fluorescent dust known as Glo Germ.
"Initially, we're looking at how well the decontamination procedures work," BioTesting Division Microbiologist Scott Jonas explained. "We'll provide that data back to the customer, who may use the data to make some changes to their procedures. Once they have a validated procedure, then we'll be looking at how that procedure impacts the integrity of the suit, and how many times the suit can be subjected to the procedure before it begins to degrade."
Soldiers from the Alabama National Guard's 690th CBRN Company aided in the execution of the plan by serving as test subjects. The three Soldier volunteers entered the chamber, each wearing a different type of protective suit. Simulant was dispersed as the test subjects walked around the chamber for 5 minutes.
"The key to this test is our ability to create a sustained, measurable cloud of particulates for the Soldiers to move around in," said Kallie Thevenot, a physical sciences technician with the BioTesting Division. "We do that with an initial forceful simulant dispersal and then we sustain the cloud with air currents generated by fans."
"We used party poppers to disperse threat particles into the air," said Patty Low, a BioTesting Division microbiologist. "Activating the [simulant filled] popper within the test chamber produced a cloud of dry simulant which we were able to sustain with air currents."
Evaluators examined the suits under a black light and removed samples from the suits to determine their level of contamination. They further examined and photographed the samples under a fluorescing microscope to provide a more accurate and permanent record of the results.
The researchers then put the Soldiers through decontamination procedures intended to remove the fallout from the protective suits. They inspected the suits again under a black light and resampled, for a second time examining and photographing the samples under a fluorescing microscope. The test was performed five times with dry decontamination procedures and five times with wet decontamination procedures.
Sgt. 1st Class William Anderson was one of the Soldiers participating in the test, and said he values the opportunity to be part of the tactics, techniques and procedures (TTP) development process. "It gives us an opportunity to provide input and make recommendations," he explained.
Andrew Reichert, a physical scientist with the Homeland Defense/Civil Support Office at the Maneuver Support Center of Excellence, said that TTPs that allow for reuse of the protective suits would give commanders more flexibility in mitigating risk while reducing the consumption of personal protective equipment.
"The BioTesting Division's adaptation of their existing technique is a great example of the contributions made to the Army by the Combat Capabilities Development Command," said Paul Tanenbaum, Ph.D., director of operational applications at the Center. "Our scientists and engineers create innovative, cross-disciplinary solutions, not only in materiel, but to support the TTPs and training, as well."