NASA is increasingly concerned about an ongoing air leak on a Russian section of the International Space Station (ISS), which has been occurring since 2019.

According to SpaceNewsBob Cabana, a former NASA astronaut who now chairs the ISS advisory committee, raised the issue during a meeting on Wednesday, November 13.

“Although the Russian team continues to search for and plug the leaks, they do not believe that a catastrophic disintegration of the PrK (module) is realistic. NASA has expressed concerns about the structural integrity of the PrK and the possibility of catastrophic failure,” Cabane said.

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“The Russians believe that continued operations are safe, but they cannot prove to our satisfaction that they are safe, and the United States believes that it is not safe, but we cannot prove to our satisfaction Russians that this is the case,” he continued. according to the news site.

A report A report from NASA’s Office of Inspector General released in September said that while the root cause of the leaks remains unknown, the ISS and Russian space agency Roscosmos have “focused their attention on internal and external welds.” .

The news comes after NASA identified an increase in the leak rate in February, according to the report. The air leak rate peaked at 3.7 pounds per day in April, but was reduced “by about a third” thanks to the repairs, according to Espace.com.

The ISS program and Roscosmos formally met in May and June to discuss heightened concerns, elevating the risk of leakage to the highest level in its risk management system, according to the report.

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“According to NASA, Roscosmos is confident that it will be able to monitor and close the service module hatch before the leak rate reaches an unsustainable level. However, NASA and Roscosmos have not reached an agreement agreement on the point at which the leakage rate is unsustainable,” the report further states.