Editing Extravehicular Mobility Unit (section)

==History==
Upon receiving the contract to build the EMU in 1974, Hamilton Standard and ILC Dover delivered the first EMU units to NASA in 1982. During the research and development phase (1975–1980), a suit being tested caught fire, injuring a technician and forcing a redesign on the regulator and circulation fan. On [[STS-4]] in July 1982, the astronauts practiced donning and doffing the suit in the Shuttle's airlock. The first Shuttle EVA was to occur on [[STS-5]], but an electrical failure on the circulation fan forced the EVA to be cancelled. The first EVA of the new EMU finally occurred on [[STS-6]] when [[Story Musgrave]] and [[Donald H. Peterson|Donald Peterson]] went out in the payload bay of the [[Space Shuttle Challenger|Space Shuttle ''Challenger'']] and tested techniques to lower the launch cradle of a solid-fuel upper stage used to boost a [[Tracking and Data Relay Satellite]] (TDRS-A) into a geostationary orbit.

Other EVAs followed on the Shuttle, notably those on [[STS-41-B]] (the first [[Manned Maneuvering Unit]] flight), [[STS-41-C]] (the [[Solar Maximum Mission|Solar Max]] repair mission), [[STS-41-G]] (the first American [[Extra-vehicular activity|EVA]] involving a woman), and [[STS-51-A]] (where two stranded satellites were retrieved and returned to Earth), but the majority of EMU uses occurred on the servicing missions of the [[Hubble Space Telescope]]. For those flights, two sets of EVA astronauts would venture out of the orbiter, thus requiring NASA to fly four sets of suits (along with repair parts). 41 EVAs using EMUs had been conducted out of the Space Shuttle airlock prior to the start of ISS assembly in November 1998.<ref name=Foot02/>

With the building of the ISS, Hamilton Sundstrand and ILC Dover refined the Shuttle EMU by making the suit modular. This allowed an EMU to be left on the ISS for up to two years and resized on-orbit to fit different crew members. The ISS EMUs also have increased battery capacity, the [[Simplified Aid For EVA Rescue]] (SAFER), improved cameras and radios, and a new caution and warning system. Another feature is an additional battery to power heaters built into the glove, allowing astronauts to keep their hands warm during nighttime passages on each 95-minute orbit.

The ISS EMUs and the Russian Orlan suits are used by crews of all nationalities on the International Space Station. The two EMUs are stored within the [[Quest Joint Airlock]].