Who’s Who at NASA: August 2005

John James, Chief Toxicologist, NASA’s Johnson Space Center, Houston, TX

Through a new, two-year joint-research partnership with Spacehab, Inc. (Webster, TX), NASA will begin testing miniature mass spectrometers, devices that can detect and measure pollutants, for advances in air quality management. Researchers aim to reduce the equipment’s size to that of a deck of playing cards while increasing accuracy and response time. Smaller monitoring devices may be useful for security measures to detect chemicals or locate explosives, and advances in air quality monitors also may better detect unsafe levels of carbon monoxide or formaldehyde. John James is involved with the development of a variety of different systems that may one day help clear the air in spacecrafts and homes by monitoring air contaminants.

NASA Tech Briefs: How is the air quality currently measured onboard NASA spacecrafts?

John James: The techniques we use to measure pollutants in the air are separated into two categories, one of which is called archival. This is where we actually take a sample of the air and bring it back to analyze in the Johnson toxicology laboratory. We have several techniques to do this: we use grab-sample canisters that capture about a fist-sized volume of air; formaldehyde badges that actually trap die formaldehyde in a matrix; and dual sorbent tubes that trap some of the pollutants in something akin to a big, thick straw. We bring these back and analyze them in various ways, and we can tell a lot about the pollutants that were present some time ago. The disadvantage of these techniques is that we do not get results for weeks if it’s from the shutde, or months if it’s from the International Space Station (ISS), after the sample is taken.

The second category, and the one we are trying to move toward, is onboard analytical capabilities. The champion of that right now is called the combustion products analyzer or compound specific analyzer for combustion products, which is handheld. What this device does is look at potential toxic products of combustion, such as a fire, onboard the spacecraft. The device analyzes carbon monoxide, hydrogen cyanide, hydrogen chloride, and oxygen. We’ve flown this for quite a few years on the ISS as well as on the shuttle. The real potential workhorse for analyzing a lot of pollutants on the ISS, however, is called the Volatile Organic Analyzer (VOA), which is about the size of two moderate-sized suitcases stacked on top of each other.

NTB: What are the mass spectrometers NASA’s working on?

James: Mass spectrometers have been around for a long time. We currently use them in our labs to measure the components of the archival samples we bring back; however, they are about the size of a car trunk. With the technology that Zyvex (Richardson, TX) is working on, if they are successful, they may be able to make an instrument that could possibly be the size of a credit card. [Editor’s note: NASA’s partner, Spacehab, has teamed up with Zyvex, a company that specializes in nanotechnology, to scale down the size of available mass spectrometers.} This remains to be proven, but it also would be a tremendous leap ahead.

The other advantage of making these instruments so small and in a relatively cheap way is that you can make a bunch of them. So, if you wanted to deploy them in many different locations, it would be possible.

NTB: Are there commercial uses for these technologies?

James: The VOA could be used for remote monitoring; for example, if you want to perform sense line monitoring in a chemical plant. There are monitors out there that currently do this, but they are not always broad spectrum. There are also military applications for the VOA. We do interact with the people who build submarines, and an earlier version of the VOA was "sunk" on a couple of sea trials to see how well the instrument performed. I also could definitely see military applications for it beyond homeland security.

A full transcript of this interview appears online at www.techbriefs.com/whoswho. For more information, contact John James at john.t.james@nasa.gov.

Copyright Associated Business Publications Aug 2005