[clvx]

Ok, This is interesting. I need something alike that can measure whatever marijuana grow facilities generate. A neighbor lives in disbelief their facility doesn't produce any smell but neighbors in a mile radius disagree with it. He is willing to set up measurements to reduce any impact but I don't have a way to collect real data beyond it's smelling. I always depends on where the wind is blowing but it's constant.

[hedora]

Voc might work. It covers most things you can smell.

If it’s a sulfur smell, it’s probably sewer gas from something decomposing or fertilizer (or an unrelated sewer problem near the facility), and a natural gas / propane detector should work. They also pick up methane, which is odorless, but is probably being produced by the same source.

[dbacar]

You sound like you are asking for a friend :).