An alarm signaling an ammonia leak sent astronauts to seek for shelter on Wednesday. The supposed leak, according to NASA officials, was a false alarm.
"At this time the team does not believe we leaked ammonia. There was never any risk to the crew," Mike Suffredini, ISS program manager said.
When the alarm went out on Wednesday around 4:00 a.m. EST, astronauts rushed to the Russian section of the orbiting lab, with emergency masks on. The ISS crew was working on experiments on the SpaceX capsule when the alarm had gone off. The six-member crew went back to the US section of the lab Wednesday afternoon.
The crew took samples of the air to check for strains of ammonia as part of a safety precaution.
"Hey everybody, thanks for your concern," Italian astronaut Samantha Cristoforetti tweeted. "We're all safe & doing well in the Russian segment."
NASA reported later on that no leaks were found after they have inspected the US section of the lab, and that "transient error message in one of the station's computer relay systems, called a multiplexer-demultiplexer," might have caused the false alarm. The error message disappeared after the flight controllers turned off the relay box and turned it on again, according to reports.
"We also saw an increase in pressure in the cabin. If you're leaking ammonia into the water loop and it finds its way into the cabin, you'd expect its pressure to go up," Suffredini said.
Liquid ammonia, which fatally toxic, flows outside the space station and is being used for cooling electronics. Prior to the flight controllers' investigation, everyone believed that the toxic chemical has made its way into the orbiting lab's water system, triggering the alarm.
No research was lost due to the incident, but experiments scheduled on Wednesday were rescheduled. The crew had to turn off the power after the alarm went off, but NASA explained that the freezers can last eight hours without power, and was designed as such to preserve the life of experiments, reports say.
The International Space Station (ISS) crew is comprised of six members, including Russians Elena Serova and Aleksandr Samokutyaev, cosmonaut engineers; and American astronaut commander Barry Wilmore.
