CAPE CANAVERAL, Fla. - NASA's spacewalking suits have oil contamination in their emergency oxygen packs, a longtime problem that could have caused the outfits to burst into flames, officials said Friday.
All 12 suits are contaminated, said Gregory Harbaugh, an astronaut in charge of NASA's spacewalk office. Each emergency oxygen pack is being cleaned, and special filters will be used to fill them to make sure no more dirt gets inside.
The work is not expected to delay upcoming shuttle flights to the international space station.
Oil can ignite when combined with the pure oxygen that spacewalking astronauts breathe. If a micrometeorite had pierced an astronaut's pressurized suit and the high-pressure oxygen pack had been turned on, ''it could have been catastrophic,'' Harbaugh told reporters.
To the best of Harbaugh's knowledge, no NASA astronaut has ever had to activate an emergency oxygen pack in space. The pack supplies 30 minutes of oxygen on top of the 8 hours normally provided by a spacewalker's primary oxygen supply.
Americans have performed 84 spacewalks beginning with Ed White's stroll outside Gemini 4 in 1965. Twice that many spacewalks will be required over the next five years, however, to assemble the international space station. The Russians finally launched their Zvezda service module on Wednesday, clearing the way for the onslaught of assembly missions.
''There's no good time for a problem to happen,'' observed Harbaugh, a veteran of three spacewalks himself.
Two astronauts are supposed to conduct a single spacewalk on the next space shuttle flight, a space station resupply mission in September. Four spacewalks are scheduled for the following station visit in October.
The contamination was discovered June 14. Drops of oil were found in a leaky oxygen regulator that was being taken apart. The same problem subsequently was discovered in all of the other regulators used in the emergency oxygen packs.
So far, no contamination has been found in any of the regulators for the primary oxygen packs. As a precaution, the National Aeronautics and Space Administration is conducting tests to make sure that even if the primary oxygen regulators were oily, they would not pose a danger.
NASA is understandably cautious when it comes to fire. Three astronauts were killed during a 1967 countdown test when a spark set off a flash fire in their Apollo 1 capsule.
Engineers have no idea where the oil came from or how or when it got inside the emergency-pack regulators. Harbaugh suspects dirty oxygen and that the oil accumulated over time.
The regulators were last taken apart and inspected in 1992, so the problem could date all the way back to then, Harbaugh said. NASA had assumed there was no way the regulators could become dirty.
''Obviously there was a flaw in that logic in that we were not adequately testing something along the way,'' Harbaugh said. ''I guarantee you that's going to change now.''
