Homebrew PCBs

Hello,

Do any of the basic homebrew PCB processes put off Carbon Monoxide? 
Do any of the processes put of any chemical that can trick/damage CO
detectors?  My middle level CO detector went off a few days ago. 
After talking myself back into the house I changed batteries in all of
my fire/CO detectors and swapped the upstairs detector for the middle
level detector that triggered.  A few days later the new middle level
detector went off.  The offending location is on a hallway ceiling
that is half way between the garage where I park my car and the
basement where I etch/tin PCBs.  I've been doing both for ~2 years
with out an alarm.  My house is heated via NG.  Any comments or
suggestions will be greatly appreciated.

Ed