[QUOTE=NinjaChick]
Augh! Yes. I live in a college dorm. Each room has a smoke detector, and they’re wired into the building’s system, with a backup battery. Which, if it is not at 90% charge or above, will cheerfully exhaust the rest of the batteries charge with chirping. Every ten minutes. Nonstop.
What you’re supposed to do in that case is call Buildings and Grounds, file a work request, and wait an average of a week for them to come and replace it. They won’t bring their own step-stool, they’ll just stomp their snow-and-dirt covered boots all over your desk chair. And then they won’t lock your bloody door on their way out.
One would think you could just take the battery out, but no. It continues chirping.
Why the hell is this necessary? It’s a dorm room - it’s not like a fire is going to start where I can’t see it. If the power goes out, and if I light a candle or something in my room, and if I leave that candle burning while I’m out, and if a magical pixie knocks over said candle and if it lands on something flammable and ignites it, then I guess it would be good to have that backup.
Right, I’m done now. deep breaths
[/QUOTE]
Sorry that the people in charge aren’t responsive or respectful of your property. Because it’s a hardwire system, it is still monitoring battery voltage, and if low, it chirps. The solution is to replace all of the batteries in a building at one shot, using high quality alkaline replacement cells-preferably during summer break. But I’m not in charge of your maintenance scheduling. 
Why is it necessary? Because people die without them.
[QUOTE=United States Fire Administration]
Each year in the United States. there are an estimated 1,300 fires in high school, private and prep school, and university dormitories. These fires are responsible for less than 5 deaths, and approximately 50 injuries and $4.1 million in property loss annually.
[/QUOTE]
These are 2001 numbers, and don’t reflect data from the Seton Hall University fire in South Orange, New Jersey, which killed three students in 2003.
One final thought-the NFPA recommends replacing smoke detectors if they are 10 years old, owing to sensitivity drift. Detectors can become insensitive to smoke, or overly-sensitive. I recommend writing the date of installation inside the cover or on the back side of the detector with a Sharpie-then you’ll know when to toss it. The other option is to purchase detectors with ultra long life lithium cells-they are meant to last 10 years and then be replaced.