Spacewalk begins after CO2 in spacesuits delay

The walk started more than a half-hour late after ground telemetry showed high carbon dioxide readings in the Orlon-MK space suits worn by both space walkers.

High concentrations of the gas can cause dizziness, nausea and other problems, but both crew members said they felt fine and ground controllers decided the readings presented no threat.

Commander Gennady Padalka, a veteran Russian cosmonaut, and Flight Engineer Mike Barratt, a U.S. astronaut on his first space mission, were scheduled to install an additional docking port for Russian space vehicles during the planned 5 1/2-hour effort.

The pair also planned to install an antenna to aid docking, and take photos of a manually operated crane used during Russian spacewalks.

Padalka is a veteran of the Soviet-built Mir space station, and Friday's spacewalk was his seventh.

The Orlan-MK's main improvement over previous versions is the replacement of the radio-telemetry equipment in the life support system backpack which contains a mini-computer.

The computer processes data from the spacesuit's various systems and warns of malfunctions. In an emergency, the computer flashes a contingency plan on an LCD screen on the right chest part of the spacesuit.

The space station's permanent crew expanded from three to six in May, with the launch of three crew members from Russia's Baikonur cosmodrome in Kazakhstan.

Follow-up story: Delayed spacewalk ends successfully

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