Instruments
People working inside tightly sealed office buildings have been known to suffer from "sick building syndrome," the result of breathing air polluted by toxic substances emitted from carpets, furniture, toner, and other paraphernalia of a modern workplace.
The International Space Station (ISS) is the ultimate tightly sealed building. Anything that enters the air stays there unless removed by an effective filtration system. Astronaut safety would be greatly enhanced by systems that can routinely determine whether the air-purification equipment is functioning properly and trigger an alert if a spill or leak requires immediate attention.
AEMC supports the development of monitoring instruments that can help to keep ISS air clean and safe, along with other aspects of its environment. Several of these technologies are being tested aboard the ISS not only for its own use, but in preparation for potential use on the Orion crew exploration vehicle and future habitats on the Moon and Mars.
Air
Rapid, reliable detection is essential to keep spills or leaks of hazardous substances from posing a serious threat to the air supply of spacecraft and extraterrestrial habitats. Even without such an event, substances such as formaldehyde commonly outgas from upholstery, insulation, and other sources in amounts which might be insignificant for a typical Earth-based room, but which can build up to unhealthy levels in a small, closed system like the ISS before human senses can sound an alarm. Detecting trace levels of certain gases can also provide early warning of fire. AEMC is funding three different approaches to monitoring the condition of cabin atmospheres: the ENose, Vehicle Cabin Atmosphere Monitor, and Tunable Environmental Laser Spectrometer.
Water
After the purification system makes recycled water safe to drink, biocides are added to inhibit the growth of microbes during storage. An instrument called the CSPE can be used to make sure that biocide levels are high enough during storage and low enough after these substances are filtered out prior to consumption.
Microbes on surfaces
Microbes are unavoidable hitchhikers aboard the ISS, as they will be in future spacecraft and in lunar and Martian habitats. The LOCAD-PTS instrument can be used to monitor surfaces for signs of potentially hazardous microbes, to ensure that cleaning practices are keeping them under control.
Leaks to space
If a faulty seal or a micrometeorite puncture allows air to escape from the ISS, or a substance such ammonia to leak from the external tubing, a handheld instrument called the Trace Gas Analyzer can help astronauts to quickly locate and fix the problem.
Moon dust
The Moon is covered with a particularly nettlesome kind of dust that poses a threat to the health of astronauts if it enters their air supply. AEMC is developing a Dust Monitor that can help to control this problem in future lunar habitats. A version of this technology may one day help to protect astronauts from similarly troublesome Martian dust.
Toxicology
AEMC adheres to the standards that NASA has set on allowable limits for dozens of chemicals that could contaminate an astronaut's air or water. For air, these guidelines are called "Spacecraft Maximum Allowable Concentrations" (SMAC). For water, they are known as "Spacecraft Water Exposure Guidelines" (SWEG). NASA currently evaluates biological hazards on a flight-by-flight basis.
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