January 25, 2010

Dynamic chamber puts chemical weapons sensors to the test

Applied Physics Laboratory engineers have constructed a first-of-its-kind chamber to test the viability of sensors designed to detect chemical warfare agents under realistic battlefield conditions.

While the use of chemical weapons was outlawed by the Chemical Weapons Convention of 1993, terrorists have increasingly deployed chemical armaments against civilian and military populations over the past decade. “Our military operates over a wide range of battlefield conditions, whether it be in the high mountains of Afghanistan, the deserts of Iraq or off ships at sea,” notes Thomas Buckley, of APL’s National Security Technology Department and the Laboratory’s project manager for this effort. “All of these are potential venues for adversary use of chemical warfare agents.”

In 2006, the Defense Department’s Joint Program Executive Office for Chemical and Biological Defense—the focal point for research, development, acquisition, fielding and life-cycle support for chemical and biological defense equipment and medical countermeasures—asked APL to design and build a chamber to evaluate technologies and systems to detect, protect against and decontaminate hazards from chemical warfare agents.

By November 2007, Lab engineers had come up with the framework for the techniques and methods that would be employed in the Dynamic Test Chamber, or DTC. Now, two years later, the complete chamber is mounted in an APL high bay. Once engineers are certain that it works as intended, it will be disassembled and moved to its permanent home at Dugway Proving Ground in Utah.

“It represents quite an aerosol science, modeling, design and engineering feat for APL and is the state of-the-art facility for chemical sensor testing, delivering quantified challenges with realistic backgrounds in a controlled manner under a defined temperature, humidity and air pressure, all of which affect sensor performance,” says Pam Smith, the APL deputy business area executive for homeland protection.

The chamber provides realistic test conditions for evaluating how quickly military detectors pick up trace level amounts of chemical warfare agents, Buckley says. “It operates over a wide range of temperature, humidity and simulated altitude while exposing the chemical agent detectors to interferents such as dust, smoke and diesel exhaust,” he says. “Its control systems will allow the monitoring, displaying and recording of data from the systems under test [SUTs] in conjunction with the DTC challenge conditions to allow analysis of the response of the SUT in real time.”

Smith says that APL has given the government a unique facility capable of delivering dynamic challenges to systems under test. “The chamber will be the first of its kind to provide agent characterization in real time for all test scenarios,” she says. “Feedback of additional system parameters will also be available and managed by state-of-the-art software that will control the chamber. All this is done while maintaining a high standard of safety and chemical warfare agent containment.”

Buckley says that the chamber is scheduled to be shipped to Dugway in January, then installed and integrated with a contractor-built secondary containment system. APL staff will operate it during verification tests with chemical agent simulants this spring, before Dugway Proving Ground staff take over the system for final verification testing and subsequently begin testing with actual chemical warfare agents.

This article appeared previously in The APL News.