"NASA uses a variety of methods to measure, control and reduce spacecraft microbial contamination for planetary protection purposes. Assembly of spacecraft hard

"NASA uses a variety of methods to measure, control and reduce spacecraft microbial contamination for planetary protection purposes. Assembly of spacecraft hardware is carefully controlled and often takes place in clean-room facilities using, aseptic techniques in order to meet planetary protection requirements. Dry heat microbial reduction techniques first used on the Viking spacecraft are still used today..." http://planetaryprotection.nasa.gov/methods/ http://planetaryprotection.nasa.gov/methods/