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

I didn't have a natural gas detector so I put this in my basement the only place in my house with natural gas. Installation is easy, just plug in. Part of the connector can be removed from the back of the device, and the main part is on a different level than the connector. Natural gas is lighter than air and propane is heavier, so they recommend placing it high in the room if you have natural gas and low if you have propane. Many negative reviewers don't seem to understand when the device should sound the alarm. Carbon monoxide is toxic in high concentrations. Natural gas and propane are non-toxic but can be explosive in high concentrations and levels are well known. In very high concentrations, they can cause asphyxiation because they displace oxygen. The packaging says the sound can last up to 4 hours depending on the CO concentration, this is UL standard. In fact, the device fails the UL test when operated in low CO levels for 30 days. This is to reduce false alarms to a minimum. The alarm is useless if people get upset and turn it off. The gas detector alarm should go off when the concentration reaches 25%, which is below the explosion threshold. The fact that the smell of heavy gas does not mean that there is an immediate danger. One negative reviewer attempted to test it with a lighter that typically uses butane. This unit is designed to test natural gas (methane) and propane only. Guarantee 5 years, after 7 years the device stops working and must be replaced. This is a security feature, not a planned obsolescence.