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After the night my husband didn't flinch at 85 decibels, I went hunting for anything louder. These actually rattled the windows and got everyone moving during our test runs.















Being woken up is great, but knowing something is wrong when you're not even home? That sold me. These send alerts straight to your phone so you can call 911 from anywhere.
















Sound doesn't travel well through closed doors and up stairwells. I learned that the hard way when a ground floor alarm went off and nobody on the second floor heard a thing.
















Hotels, Airbnbs, and RVs almost never have CO detectors. I started packing one after reading a news story about a family in a vacation rental that still haunts me.














