The Silent Killer.
Now that I have your attention, make sure you that your smoke and carbon monoxide detectors are present and in proper working condition. I know that chirping noise that always seems to happen at 2am is annoying, but make sure to put a new battery in the next morning.
The Gilbert Fire Department recommends you check your alarms 1x per month, clean your alarms every 6 months, and change the batteries once a year.
For more information check out www.gilbertaz.gov/departments/fire-and-rescue/community-programs/fire-safety or call 480-503-6300.