breathability alert

Breathability seems to be calculated based on samples of where the dupes are and how much O2 (or PO2) they have access to.

For most circumstances this should work just fine, but underwater digging (and a few other edge cases) seems to throw it outta whack.

Perhaps suspend a Dupe's participation in the calculation until they leave the water (say... when they shake off their feet?)

Overall the metric is really useful, I hope the sampling can be refined so it gives an accurate portrayal of the colony.