For somewhat unclear reasons that seem at first glance to be an over-reaction, NASA officials today ordered all five non-Russian astronauts on ISS to shelter in the Dragon capsule docked there while the two Russian astronauts did repair work on the new air leak in the Zvezda module on the Russian half of the station.

Following new leaks, Roscosmos has elected to proceed with a more extensive repair operation on Friday, June 5. Out of an abundance of caution, NASA has directed all four of the agency’s SpaceX Crew-12 members and NASA astronaut Chris Williams to assume an elevated safety posture in the Dragon spacecraft while the repair is underway.

As it turned out, the Russians only did “measurements” today, no actual repairs, and so NASA then canceled its “shelter in place” order.

This new air leak, first detected in May, has been estimated to be equivalent to the loss of about one pound of air per day, which is relative low compared to the loss rates seen from 2019 through 2025, as shown in the lower right corner of the graphic below, taken from a 2024 inspector general report. In late 2025 the Russians were able to stop those leaks, only to have this new one return last month.

Figure 3 from September 2024 Inspector General report, showing Zvezda’s location on ISS, as well as the station’s leak rate at that time.

Unless the Russians planned some radical repair plan (unlikely), sheltering in Dragon seems overkill. For several years NASA’s policy has been to simply close the hatch between the American and Russian sections of ISS during dockings to Zvezda. It likely also did this during earlier repair work. For the agency to now escalate its safety precautions suggests either the repair work was more risky, or NASA administrator Jared Isaacman wanted to make a political and engineering point that would be noticed by the mainsteam press.

If the latter, Isaacman got what he wanted, as there have been numerous stories today from many mainstream outlets, with some misreporting the story as if the leak was suddenly new and required an emergency evacution (see here, here, here, and here).