Yes, you would have to find a foolproof way of preventing the gas from coming into the structure. I think an inline fan would do it. Sewer gas contains methane but not in concentrations that one would generally call dangerous. Not flamable, certainly not explosive. It stinks of course but dangerous, MMMM.............not really. Not here anyway.you would have to find a fool proof way to make sure the air kept a 1 way flow. you wouldn't want the methane gas coming back in the house. not worth the risk if you ask me. but what about the vent stacks and blow it out to the top of the building?
Venting out of a vent stack kind of defeats the purpose of the heat register signature being detected although generally would be a better idea than say out a wall as a vent stack could be anything really as far as a heat signature is concerned. Don't really understand the risk per say. What risk? Gas?? You would get the same gas coming in if a P-trap was alowed to dry up. No big deal really, just open a window. Or not Think about it, have you ever heard of a house blowing up because of sewer gas?? No you have not, nor will you ever. If that was the case the entire plumbing scheme as it exists today would be untennable. Code would not allow for even the slightest possibility of houses blowing up because a p-trap dried up. So please let's not bring this up again. it's ignorant at best, stupid at worst. I am not the first or only one to think of this, I know that now as said in my opening paragraph it is as I thought it might be. But this is a great idea and could be usefull in the right situation. Like a stealth closet for example. If anyone has something constructive to offer, preferably something that makes sense or is based on relevant facts then please let's hear what you have to say. If your only thrill in life is pissing in someone else's picnic basket then don't blame me for calling you a "DICKWAD" I just call em as I see em.