The challenge is to fight through the zone, relying on O2 canisters and indoor areas to provide air rather than the many air domes. Given the plentiful supply of all three, the hardest part of this challenge is remembering not to activate the domes. If no one activates a dome, the challenge will complete as soon as someone comes within activation range of the exit. If a vault hunter wears a shock nova shield, uses it up, and it goes off and triggers an air dome, this does not count as activating it, and the challenge is still attainable.