system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5: If creatures such as tardigrades can survive in extreme conditions such as the vacuum of space and deep under water, how can astronauts and other space flight companies be confident in their means of decontamination after missions and returning to earth?

My initial post was related to more of bacteria or organisms on space suits or moon walks and then flown back to earth in the comfort of a shuttle.
gpt
With wide enough boundaries, they can't. If a tardigrade, or mad space bacteria, can survive a ship going from the vacuum of space to re-entering earth's atmosphere at enormous heat and then being barracked by the thick earth asmosphere ,then there's nothing that can reasonably be done. It's considered sufficiently unlikely to not be a realistic concern.