E'Angela, I'm sorry, I wrote this back in January but didn't post it.

I'm not an expert on septic systems, however, my understanding is that a newer, professionally installed, well maintained system shouldn't actually outgas much if any.  Both the tank and the drainfield are several feet underground, so all the liquid actually goes down, and since it's anaerobic, there shouldn't be much if any gasses.  I know mine has no odor.  If you think about it, we wouldn't be allowed to have it near the house if it were dangerous.  What I was told by my septic maintenance person, was that there isn't really much if any digestion going on, but mostly separating the liquid from the solids and the liquid then soaks into the ground.  That's why we need to get them pumped so often.

Where I could see an issue would be with an older system, that is clogged up, or the drainfield has wonderful green grass above it indicating improper draining.

Once again, I'm not an expert in septic systems.  You might also ask a septic installer about that as well.

Allen Engle