Review on 🔌 Kidde Nighthawk Carbon Monoxide & Gas Detector, AC Plug-In with Battery Backup, Digital Display by Sheppard Priest

I have been using these Nighthawk Carbon Monoxide and Explosive Gas Detectors for over a decade. I've found them to last about half a dozen years before failing. They drain 9 volt batteries quickly when the power goes out. So if you have a power outage for more than a few hours, the device will have to change the battery within a few weeks. There are many comments about these devices giving false positive results. I've never had a single false alarm. Is always. But I had many alarms. These devices are not natural gas detectors, they are hydrocarbon detectors. This means they will work with almost any volatile hydrocarbon that comes their way, including humans/animals leaking gas, using solvents around them (alcohol, acetone, gasoline, nail polish remover, witch hazel, etc.), cooking fats and machines, laundry. Pre-cleaner, paint fumes, nail polish fumes, etc. If you smell hydrocarbon, then the unit is pretty much smelling it. We have one above our gas dryer, and while I'm a PhD in Physics and Biochemistry by trade, I was amazed at the range of conventional detergents (or oils/greases/petrol on clothes) that can set off explosive gas alarms. This tells me that the explosive gas sensor is not selective, it cannot distinguish between different hydrocarbons very well, if at all. That means you have to think about where you put this device and what activities are going on nearby.