You may be right, Mike. It kind of depends on how large the basement is and how much air the exhaust fan is moving. What got my attention were the phrases “aerosol clear lacquer” and “It got kind of foggy a time or two”. Maybe I’m just overly cautious.
You should know that it has more to do with the chemical composition of the substance in question. Different chemicals will ignite at different saturation density levels in the air. Laquers can ignite at a relatively low density. I would be very very careful and never assume that it can’t ignite because you think the ventilation is adequate. If it is foggy, or you can smell the fumes, then it is probably past or close to the critical saturation point. I never recommend using any kind of aerosol near any potential ignition point (furnace, Heater, Garage Door opener etc…) Stay well away from anything that can spark. I work on our enclosed front porch. It is so well ventilated that I need to wear a coat this time of year. I have a small electric heater I use to warm it up as much as possible before I start, then shut it off and unplug it until I am done and I am sure that there are no remaining fumes on the porch.
I just put a small booth together this weekend for under $50. Nice!
Since I mostly use acrylics I’m not concerned about that thing exploding in my face. No smell, no fumes and no paint getting were it shouldn’t. And spraying any time I like to. I’m happy!