What units of measurement are applied to space adaptation syndrome (SAS) or space motion sickness?

Astronauts going into space or spending time on the International Space Station may become ill (sick) with space adaptation syndrome (SAS) or space motion sickness. In 1985, after Senator Jake Garn tagged along on Shuttle Mission STS-51-D as a payload specialist, the manner in which motion sickness in outer space was measured permanently changed. Senator Garn had the most extreme reaction to space motion sickness that had ever been recorded.

Thanks to the debilitating motion sickness Garn's experienced on the space flight, the Garn Scale immediately became a unit of measurement. Jake Garn made a meaningful mark in the Astronaut Corps because the Garn Scale represents the maximum level of space sickness that anyone can now ever attain. It is used to determine and indicate in a written record if a person is totally sick.

Someone in space is totally sick or incompetent (ill) if one Garn is detected. Most individuals will maybe get to a tenth of one Garn, which is considered a high mark.