Originally Posted by
Water pilot
Alarms are not expensive at all, they should be required equipment. In my state (Washington) all bedrooms are required to have both smoke and CO alarms and many companies make combination alarms. They are available in AC, DC, or battery powered, some with 20 year batteries. Unfortunately I have not found any DC alarms that would announce "Carbon Monoxide alert" in English, yet another high pitched beep that you have to figure out is not as useful as I would like, but better than nothing.
In the UK, it's easy to buy a domestic battery-powered CO detector. I'm guessing those would work just fine in a cockpit.