I once threw a man out onto the solars trying to murder him. He was screwing around with his genetic code (he was a geneticist, go figure) and he had his standard attire and a breath mask + oxygen on.
He survived a whole 20 minutes until I stepped out there and kicked the stuff out of him, he wasn't in critical, either! He was epileptic and he blacked out, and never woke up. Nothing but a breath mask...