mgb - What do you mean by 'pure oxygen atmosphere at ... partial pressure'? Is that contradictory or do I miss something?I hadn't studied the details of the accident.
A pure oxygen atmosphere at a 21% partial pressure makes sense (and was used in Gemini/Mercury). Inward opening plug seal doors without explosive bolts are used on all commercial aircraft it balances the real risk of a leak with the few times during the flight when you can safely open the door.
It seems from the account that it was a very very badly thought out test rather than the design that was wrong. In particular pressurizing it to a flight pressure differential but still using pure oxygen was insane!