Found the following info on-line. Hope it is helpful ..
Most CO sensors use a tin(IV)oxide semiconductor device. When heated
and exposed to a reducing gas the conductivity increases. Early sensors
were heated to about 300 C and were not very selective for CO since they
also responded to hydrocarbons. Variations of this device are used for
explosive gas detectors (methane, propane etc.) and breathalizers for
alcohol. Newer CO detectors run at 80 C for most of the time which
eliminates false triggering, however crude builds up on the detector at
this temp, so they are programmed to heat to 320 C every so often to
clean themselves. During this time they are inactive, which isusually
not a problem since CO usually builds up slowly.
Actually that would explain why the CO detectors and for that matter even Propane leak detectors
might false alarm...hydrocarbons
Hydrocarbons are contained in most products except maybe Latex paint. Wood preservatives, Paints, Stains, Varnishes and most Polyurethane sealants, Sikaflex, and many items. The outgassing we may not notice because we get used to the odors but they are there. A closed environment such as a bus or rv with a limited air flow and fixed volume allows the smallest amounts of the released gasses to build up over time.
These odors or gasses are usually ignored by the human nose after exposure. It's like you don't notice how bad the bathroom smells after a big stinky until you get into fresher air. It's not that the human body doesn't detect it by smell but it can detect things that we are unaware of and respond by allergic reaction or even athsmatic responses.
I am severely sensitive to molds as is my wife. I can smell certain molds in a matter of seconds long before other people even notice, I start reacting within minutes and the results are not good. My wife just went through the allergy testing and when they hit the black and brown molds she nearly went into anaphylactic shock with a couple of hours.
Please be aware that cleaning products can cause not only air quality problems but after long exposures you can become allergic to even the faintest of odors. My nemesis is Chlorox Cleanup.with Pine sol a close second. This I discovered after doing extensive cleaning to eliminate mold and now I am allergic to the cleaning products smells.
I guess I got off the topic slightly, Sorry.. But after living is a decidedly moldy or cleaner saturated environment ( My old RTS ) I developed a few more ailments. I just added that because I think that its possible that the electronic detectors that we rely on to monitor our environments may also be reacting to odors other than specifically intended.