A popular TV show (Mythbusters) recently tested an infatable bra to see if it would burst. It took depressurisation to altitiudes in excess of 47000Ft (altimeter they were using didnt go any higher) to cause an appreciable increase in size, but didnt burst. Conclusion was if you stepped out of the shuttle in orbit, it might burst but that would be the least of your worries.
Take a football and test it, pump it up hard and take a press reading. Then pump it up untill it bursts (noting the pressure as you go) if its hard at 20 PSI and bursts at 100, its not likely to blow in a cabin.