Astronaut Clay Anderson activated the system Tuesday to operate at 50 percent capacity and then used a sound meter to measure noise levels. National Aeronautics and Space Administration controllers in Houston will evaluate the system, which is designed to supply sufficient levels of oxygen for a station complement of six crew members.
The Expedition 15 astronauts are also preparing for the arrival of the station's next crew. Anderson and cosmonauts Fyodor Yurchikhin and Oleg Kotov will be returning to Earth when Expedition 16 crew members Peggy Whitson and Yuri Malenchenko arrive at the station Oct. 12.
Accompanying Whitson and Malenchenko will be spaceflight participant Dr. Sheikh Muszaphar Shukor of Malaysia, who will return to Earth Oct. 21 with Yurchikhin and Kotov, NASA said. Anderson will remain on the station with Expedition 16 until his replacement, astronaut Dan Tani, arrives on space shuttle Discovery later in October.