Dr. John Bonnell, THEMIS electric fields scientist and instrument lead, puts on the bunny suit required when entering a clean room. This movie is sped up many times its original speed so as you may be able to tell, getting dressed to go into a clean room can take a while (about 10 minutes). These suits are required to keep the instruments as clean as possible. Even our natural shedding of skin can cause harm to instruments that will fly into space.

More specifically, engineers wear clean room suits to keep body oils, skin flakes, and hair away from flight hardware, to keep fibers from clothing away from flight hardware, and (usually) to help dissipate any static charging that one picks up moving around in the work environment. Depending upon the stringency of the cleanliness spec for a given mission, one may have to even be "blown off" before entering the clean area so as to further reduce the possibility of contamination.