At about 07:00 GMT on Saturday, ISS cosmonaut Sergei Ryzhikov told a specialist at the Mission Control Center, located near Moscow, that the pressure in the intermediate chamber of the Zvezda module was 678 millimetres of mercury. The pressure stood at 730 millimetres of mercury on Friday evening, right after the hatch of the compartment was closed. Thus, the pressure in the chamber decreased by 52 millimetres of mercury over 11.5 hours.
A small air leak was first detected at the ISS in September 2019. Russian cosmonauts have since found two rips in the access section to the Zvezda module and sealed them both in March 2021. According to Russia's space agency Roscosmos, the air leak poses no threat to the ISS crew.