The VCAM development unit enables the testing of critical components before proceeding with the flight build.

The development unit for the gas chromatograph subsystem for VCAM is currently under test.

Gas consumables are installed as a subsystem that can be removed by the astronauts on the space station.

Vehicle Cabin Atmosphere Monitor (VCAM) can provide a means for monitoring the air within the enclosed environments, such as the ISS, Crew Exploration Vehicle (CEV), a Lunar Habitat, or another vehicle traveling to Mars. Its miniature preconcentrator, gas chromatograph (GC), and mass spectrometer can provide unbiased detection of a large number of organic species. VCAM's software can identify whether the chemicals are on a targeted list of hazardous compounds and their concentration. Its performance and reliability on orbit along with the ground team's assessment of its raw data and analysis results will validate its technology for future use and development.

VCAM pulls in air from the ISS cabin through an inlet port embedded in its front panel; the air passes through a particulate filter for analysis. Onboard software evaluates targeted compounds that need to be monitored for the crew health.

A VCAM calibration gas is used to periodically quantify how the preconcentrator, GC, and mass spectrometer are actually performing. The raw data, calibration data, and analysis results are all sent to the ground for further assessment to validate the instrument's detection, identification, and quantification results.

The VCAM system is a stand-alone instrument that operates autonomously but can be commanded by either crew or ground personnel. It carries its own gas supplies for sampling operations, cleaning, and calibration. Several VCAM processors control the measurement and analysis processes, monitor housekeeping sensors and actuate the valves that control the flow of gas. Commercial backing and turbo-molecular drag pumps maintain the vacuum required to do ion-based mass spectroscopy.