Shirtsleeves on Mars?

[Urwumpe]

Sudden depressurization has happened under spaceflight. This was exactly what happened during Soyuz 11. A valve opened short before re-entry, and the crew got killed by the low pressure

Wasn't exactly sudden, since it took 90 seconds until the pressure dropped below the limits for humans to stay awake.

The Challenger accident was likely the only true explosive decompression in spaceflight, since the destruction of the spacecraft and the primary structure of the cabin resulted in a sudden loss of pressure to the near vacuum at 25 km altitude.