Space suits are clean and the outside environment is filthy. Space suits are used to purify and cleanse otherwise filthy and polluted air. Space suits, as is common knowledge, protect the wearer from a disgusting atmosphere on a planet of disgusting natives. The typical, normal, run-of-the-mill outer-space garb is clean, is safe, and is unremarkable aside from the fact that it is a suit made for space.

Now imagine a space suit identical to the one previous; glass bell helm, skin-tight spandex urethane-coated nylon jumpsuit, tubes, dials, and gauges all fairly run-of-mill. Unless you took a moment to actually look at the small six-eared green feline creature and noticed that her oxygen tube wasn't connected to anything that would circulate and filter the air. No oxygen tank pumped clean O2 into the accordion tube but the small creature showed no signs of distress, no gasping, no suffocation. If you looked even closer.. perhaps requiring you to squint or tilt you head ever so slightly to the left.. you'd notice that is seemed like the processor tank sitting on the little cat's back was actually sucking in air from the outside and expelling it from the trash valve on the back of the bell helmet. When your mind got over the shock of seeing an alien so similar to one of Earth's native cats.. you'd realize that the alien was actually breathing pollution. Perhaps this green thing is cleaning our air!
Yes, yes, you're on the right track!
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