[habu68]

I have run my single burner propane forge in a 10x12x12 foot shop with the walk in door, window and ceiling vent fan running. In the first 10 min of running my forge in this room I have watched my digital co sensor run from 0 to 999 parts per million CO. The forge is well tuned but the cold start does not give a full burn of the carbon in the propane. 900 parts per million CO will cause loss of consciousness in less than 5 min. 135 ppm will kill over longer exposures. After my forge reaches operating temps my CO levels in the room drop back to 0, but remember that you are still producing Co2 and burning available oxygen. Coal, charcoal, and fuel oil will also produce CO.

I have had two close encounters with CO in automotive settings they are not fun. My personal opinion is that a CO detector is as necessary as safety glasses. I recommend the Nighthawk Digital CO unit, the digital read out gives you a visual warning prior to the nightmarish alarm going off and waking the neighbors, also this unit has a cumulative exposure algorithm that sets the alarm off when you have a low exposure over a long period of time.

Disclaimer: I am not associated in any way with the Nighthawk company. I only know that they have saved my life on more than one occasion.