dont need to use them to be educated on the dangers the can have on PEOPLE...fuck the plants man your putting people in your home at risk if your not using them properly. i dont really understand what more information you need to get it through your head that its not the fucking plants you need to be worried about.
but good luck finding someone else that "uses" them as most people with 1/2 a brain probabally dont use them in thier home.
now if your heating a shed outside or something then the above comments dont pertain to you. if this is the case then your plants will be fine. Co2 and CO are gasses and they wont effect your plants rezivoir. the CO2 will aid in plant growth.
anyways, im not trying to be a dick but if your using this think in your house then you potentially putting peoples lives at risk to keep some plants warm and if thats the case you my friend belong in jail. if its not the case then my comments dont pertain to you like i stated above and shouldnt be offensive. if they do then im glad your offended as i dont really care