"Hyperbaric treatment" Simulation audio heard on ISS live feed sparks concern for astronauts

Just before 6:30 p.m. EDT on Wednesday evening, an alarming audio was heard on the usually quiet live video feed from the International Space Station, currently home to Crew 8 and the Starliner Crew.

“If we could get commander back in his suit, get it sealed, and step into procedure 5.180 for suited hyperbaric treatment section three for oxygen post splashdown that would be my recommendation," said a female voice as the video feed continued to show views of Earth.

The voice continued, referring to decompression sickness, the hunt for a flight surgeon and locating a hospital in Spain specializing in treatment of decompression before going silent, triggering alarm among the space community that something was deeply wrong and an astronaut might be hurt. The concern lasted just over an hour until NASA reassured everyone: it was a drill, inadvertently aired on the feed.

NASA said the astronauts were currently sleeping and all was fine on the orbiting outpost.

What triggered the alarm about the ISS

After the female voice spoke about the need for oxygen post splashdown, it was followed by a moment of silence. Then the female voice returned, “This is a best effort treatment. Whatever you can do is going to be better than doing nothing ... prior to closing the visor, and pressurizing the suit, I would like you to check his pulse one more time.”

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More silence followed before the speaking continued. "How much oxygen do we have remaining in minutes. I would like to have 100% O2 flowing via mask while you get the suit on. Prior to closing the visor and pressurizing it, I would like you to do a pulse check one more time, and then step into 5.180 section three."

Just seconds later, she continued, “At this point because the hypobaric exposure is a big problem, and given his exam, I’m concerned there are severe DSC hints, so I would recommend getting him in the suit as soon as possible. And getting oxygen as best as able during that process. The best thing would be to get him in the suit asap."

DSC stands for decompression sickness ? aka the "bends" ? an illness caused by a quick decrease in pressure.

The exchange immediately triggered concern that there'd been an accident on the orbiting outpost and an astronaut was experiencing decompression sickness.

The female voice went on to state that she was stuck in traffic and trying to get another flight surgeon to mission control as soon as possible. She stumbled as she stated, "the prognosis for commander is, um...tenuous at this point to keep it generic".

Seconds later she once again broke the silence stating that she had found a hospital in Spain that specialized in hyperbaric medicine ? which is treatment given to those experiencing decompression sickness.

After details and a phone number were given, the live feed went silent.

Quick concern over what happened on the International Space Station?

The exchange only lasted minutes, yet word quickly spread throughout X (formerally Twitter). Chris Berger of NASA SpaceFlight.com, a space site, posted the exchange, and said he was seeking answers.

With a spacewalk initially planned for Thursday morning, concerns esclated. Had this been a training accident? A full blown medical emergency?

NASA said it was an ISS drill

Just after 8 p.m. Wednesday, more than an hour after the audio was heard, NASA posted a statement on X.

"There is no emergency situation going on aboard the International Space Station. At approximately 5:28 p.m. CDT, audio was aired on the NASA livestream from a simulation audio channel on the ground indicating a crew member was experiencing effects related to decompression sickness (DCS). This audio was inadvertently misrouted from an ongoing simulation where crew members and ground teams train for various scenarios in space and is not related to a real emergency. The International Space Station crew members were in their sleep period at the time. All remain healthy and safe, and tomorrow’s spacewalk will start at 8 a.m. EDT as planned," the statement read.

Comments of relief followed. Some even referred to the incident as a modern version of The War of the Worlds radio drama broadcast, which frightened listeners in 1938 ? as many believed it to be a true news broadcast.

Thursday morning, NASA announced the scheduled spacewalk was postponed due to a spacesuit discomfort issue. No further details were given.

Brooke Edwards is a Space Reporter for Florida Today. Contact her at [email protected] or on X: @brookeofstars.

This article originally appeared on Florida Today: NASA says no emergency on ISS after alarming audio about hurt astronaut