Researchers at the U.S. Army’s Edgewood Chemical Biological Center (ECBC) and several partner organizations have developed a new test method standard for the U.S. Department of Defense called the Low Volatility Agent Permeation (LVAP) system.
LVAP is a contact-based testing method for assessing permeation of threats such as VX nerve agents through protective equipment. The system uses a sorbent pad to collect the total permeated mass of contaminant, and a weight is applied to the fixture, ensuring that all layers are in good contact.
Traditional methods of measuring permeation are dependent on collecting vapors of the permeated contaminant. This can be less accurate for low-volatility contaminants, since the vapor concentration may not represent the potential hazard that has permeated through.
“The modeling of this method was remarkable,” said Terrence D’Onofrio, Ph.D, principal investigator for this research. “We can describe how VX interacts with different materials, and predict how much will come through over time, using these physics-based approaches.”
The researchers can predict the levels of permeation that occur over time, guiding experiments to the enable focus on critical time points. The modeling also enables comparison with data obtained by traditional vapor-collection methods.
“This ability to predict the changes over time fills a huge gap from the previous methods,” says D’Onofrio.
LVAP has already had an impact on personal protective equipment and laboratory procedures used at ECBC. D’Onofrio and his colleagues within ECBC’s Engineering Directorate used LVAP as part of a safety initiative to test laboratory gloves against high-concentration VX solutions. Through the use of LVAP, they were able to demonstrate that the gloves offered protection for the laboratory scenario tested.
LVAP is the result of multiple years of ECBC research, with support from the Joint Science and Technology Office (JSTO), Natick Soldier Research and Development Center (NSRDC), Deputy Under Secretary of the Army for Test and Evaluation (DUSA TE) and the Joint Project Manager for Protection.
This LVAP method is now being transitioned to ECBC partners at the West Desert Test Center at Dugway Proving Grounds. Beyond DoD, domestic elements such as the Federal Bureau of Investigation and the Department of Homeland Security, have discussed using LVAP to test their First Responder suits. British Agencies have also expressed interest in the method.