Anything that burns creates carbon dioxide (co2) as a by product of combustion. Throw off the fuel/air ratio and the by product is carbon monoxide (co).... DEADLY. A carbon monoxide detector should be in any home that uses (especially) natural or LP gas, wood burning stove or co2 generator.

Most carbon monoxide (co) detectors will go to alarm when carbon dioxide (co2) reaches abt 10,000ppm. That concentration is short of lethal (abt 20,000ppm) but abt the unconscious level, hopefully the alarm will be enough to make you aware there is a problem.

Sorry, I can't LOL at the possibility of someone dying trying to gain some extra weight from thier grow.