Question: What is the worst situation you had to deal with

Andrea Boyd answered on 15 Jun 2016:

There are three potential emergencies on the International Space Station: Fire, Depress (leaking hole) and Ammonia (Toxic Atmosphere).

We have very loud alarms for each and of course safety procedures that everyone knows by heart because we have practised them so. many. times.

Anyway – one day I was not working but I was oncall and the Flight Director asked me to come on console for one hour to help with a quick thing. So I did and ten mins after I arrived the alarm for ammonia went off! This is the worst thing that could possibly happen on the station because you can’t recover from it and clean the air ever again – it means speed-float to the Russian segment, close the hatches and game over for the European, Japanese and American science labs.

Everyone in space and in flight control around the world all responded like clockwork doing all the correct emergency procedure steps. Even though were were running the emergency procedure we thought it was a false alarm because it stopped. Then the alarm went off again and we checked the pressure deltas and they told it was real. Crew had already put on their ammonia masks and were safe in the Russian segment taking measurements of the air to confirm it was safe in there. Their readings all said safe, but our telemetry still said ammonia leak so we continued working the procedures. My console room was filled with concerned astronauts and colleagues, crowded around my workstation. Everyone worked the procedures and stayed calm and did our jobs.

In the end thankfully it turned out to be a faulty relay compounded with a faulty combination of signals on a NASA computer which gave a very real ammonia alarm so we could reopen the hatches and clean up to get back to normal operations.

That ‘Andrea can you help us on console for 10 minutes’ turned into a very intense few hours!!