VEHICLE CABIN ATMOSPHERE MONITOR (VCAM)
Research Area: Air, Water and Surface Monitoring
Expedition(s): 19- 28
Principal Investigator(s): ● Ara Chutjian, PhD, California Institute of Technology, NASA’s
Jet Propulsion Laboratory, California
RESEARCH OBJECTIVES
Vehicle Cabin Atmosphere Monitor
(VCAM) identifies gases that are
present in minute quantities in the
International Space Station (ISS) air
that could harm the crew's health.
Experience in monitoring the ISS
environment provides a new
understanding of the closed
environment and will be applied to
operations of future spacecraft and
long-duration human exploration
missions.
EARTH BENEFITS
Instruments larger than VCAM
monitor the air in enclosed systems on Earth, such as onboard submarines. Small portable units
are used in the field to monitor the environment.
SPACE BENEFITS
VCAM will protect crew members by informing them of the slow buildup of potentially harmful
chemicals in their breathing air. While VCAM’s library contains species that are known to be
present in the various life-support systems, VCAM can provide data that allow ground scientists
to identify compounds that were not expected. These same functions of detection,
identification, and quantification can be used in the event of a chemical spill or release.
RESULTS
VCAM’s performance was sufficient to detect and identify 90% of the target compounds at their
180-day Spacecraft Maximum Allowable Concentration levels. About 1 month into operations,
VCAM suffered a mass spectrometer heater failure. VCAM was recalibrated to operate without
the heater and returned to nominal operations after a patch cable, delivered on STS-134/ULF6,
was installed to power a backup heater. VCAM and Grab Sample Container (GSC) analytical
results were in good agreement for 10 compounds: 1,2-dichloroethane, acetone, benzene,
carbonyl sulfide, dichloromethane, ethanol, isoprene, limonene, toluene, and the xylenes.
While VCAM could not quantize 6 compounds (1-butanol, 2-butanone, 2-propanol, ethyl
acetate, hexamethylcyclotrisilazane, and octamethylcyclotetrasiloxane) prior to the heater
View of VCAM during gas supply change-out during Expedition
30.