Small tools, big impact: piecing together a bigger picture

Courtesy Photo | Small tools, big impact: piecing together a bigger picture.
March 19, 2020

Warfighters will soon be able to attach a new technology to their uniforms to collect a sample of chemicals present in their operational environment. The technology is a passive, chemical sampler that complements a current technology — the handheld detector, which immediately alerts the warfighter of chemical warfare agents present at concentrations considered suspicious.

Warfighters surveying an area for unknown chemicals at varying toxic concentrations carry the handheld detector (while wearing masks and protective suits, and carrying compressed air for breathing). However, the detector could raise a false alarm that a chemical is present, may not detect a chemical if its concentration is below the minimum value programmed in the detector, or may misidentify the chemical class of a compound that is in the environment. The passive sampler is a robust complement to the handheld detector and gathers information the detector may have missed.

The new tool passively samples the chemicals in the space a warfighter is surveying. An analysis of the chemicals sampled reveals the identity and quantity of each chemical and also suggests the possible uses of the site in which the chemicals are present, e.g., to manufacture chemical warfare agents. This tool is a result of research funded by the Defense Threat Reduction Agency and carried out by scientists at the U.S. Army Combat Capabilities Development Command Chemical Biological Center (CCDC CBC).

The passive sampler is lightweight, clips on to a warfighter’s uniform, and requires no power to collect a sample of chemicals that range in amounts from high parts per trillion to low parts per million. Scientists analyze these high-to-low values to understand if the chemicals collected during the survey are present at levels safe for short-term exposure or at levels immediately dangerous to life and health. A typical site survey of 30–90 minutes in duration is needed to accumulate adequate samples that characterize the site in which the agents are present. The data collection time frame matches how long a warfighter is able to wear the protective mask and breathe the supplied oxygen while conducting the survey.

Because the passive sampler picks up any chemical it encounters, the composition of the sample may contain thousands of compounds. For example, each warfighter gathers a different sample based on their activity and movements, what they carry on their person, or if they have recently fueled or operated equipment requiring gas or diesel. To identify each component in the sample, the analysis is normally performed in a laboratory setting with the use of sophisticated instruments. Chemicals identified may include those related to the manufacture of a chemical warfare agent or those associated with the breakdown of the agent.

The passive sampler collects all chemicals it encounters and, through subsequent laboratory analysis, informs warfighters on the activities that take place at the site: whether the site is a place for manufacturing or breaking down chemical warfare agents, or whether the site serves another purpose. At a minimum, this information can educate warfighters on the diverse nature of sites related to chemical warfare agents.

During a National Guard Civil Support Team exercise with the advanced chemical, biological, radiological, nuclear, and explosives training branch at CCDC CBC, analysis of data collected by the passive sampler actually distinguished between a simulated nerve-agent facility and a simulated blister-agent facility.

The clip-on, passive chemical sampler will soon become available to warfighters. Data from the sampler provide better situational awareness of the operational environment, allowing commanders to make more informed decisions.