After you mark the ends of your zone and fill out the paperwork you begin to head back to base. But you're stopped when you see your coworker slumped over his desk completely asleep wanting to keep him out of trouble you attempt to shake him awake but the long hours have put him into REM sleep and you are unable to rouse him. But you had a good day and decide to go the extra mile and personally carry him back to base so he doesn't recieve penalties for wasting company provided oxygen. And so you march along with a practically dead body on your back all the way back to finish your report.

Looks kinda good, you did nice work here

The dude's reached critical oxygen levels cause of faulty equipment, luckily the automatic safety system in surveyor team suits activate a rescue beacon, pop an emergency supply and Chloroform them to sleep so the emergency supply lasts longer.

Edit: yeah I meant Chloroform, edited that to match, can't believe I forgot that especially given it's related to one of my favorite jokes.
Additionally you cannot be poisoned by excess oxygen, more so it's a really funny little oversight by the respiratory system wherein the lack of waste/non-oxygen impurities, results in the Exhalation cycle to not trigger, meaning you just stop breathing, leading to suffocation.