He had to release a valve to partially depressurise his suit so he could squeeze back inside.

All can rip holes in propellant tanks, depressurise a spacecraft -or smash another satellite, causing yet another cloud of debris to erupt.

It depressurises and the materials underneath rise very, very quickly.

We aren't NASA and we can't waste five hours depressurising you down to run on pure oxygen.

The depressurised and unbalanced aircraft then made an emergency landing at another airport at Magan, some 12km away.

Oxygen would have run out in 12 minutes in a depressurised cabin, rendering the passengers unconscious, according to one expert.

Dozens of passengers were taken to hospital complaining of headache and earache and suffering from nausea after the plane depressurised rapidly.

Basically, in the event the plane cabin depressurises, you're instructed to put your own oxygen mask on before you help others with theirs.