We recommend the following detector IN ADDITION to ONE UL 2034 listed detector.
CO Experts Low Level Carbon Monoxide monitor
If your family includes anyone OTHER than healthy adults, such as:
infants, children, elderly, asthmatics, immune compromised persons, etc.,
then you NEED a CO Experts low level CO Monitor.
"Exposure to a low concentration over several hours can be as dangerous as exposure to high carbon monoxide levels for a few minutes..." US Consumer Product Safety Commission Fact Sheet # 5010.
These monitors are designed to provide MUCH MORE information than the UL listed alarms sold in big box retail stores. In fact, alarms that meet the UL standard are PROHIBITED from ringing at low levels (so as to not bother 911 call centers and gas utility service dispatchers).
CO Experts low level monitors are powered by a 9 volt battery. They are available from www.aeromedix.com