The house we bought new 11 years ago had these evil devices. Each bedroom has one, and the kitchen as well. I didn't realize this for a couple of months, and I learned it in a rather aggravating way...
The master bedroom is on the ground floor, with a tall ceiling (about 13 feet). My folding ladder is about 8 feet high. Those detectors (don't remember the model) were really bad, and really sensitive to high humidity. We moved into the house in December. When spring arrived (along with that wonderful North Carolina humidity), the alarms (ALL of them) went off...about 3 AM. I had to get the ladder, drag it around corners into the bedroom, stand on the next-to-the-top rung (because the top is just asking for trouble), reach up, yank the offender out...and find out that removing the battery didn't shut the little monster up. I had to remove wire nuts, disconnect wires, keep from electrocuting myself, keep from falling, refrain from cursing too much, and do all this in a sleep-hazed condition...so that we could shut the little devils up and get some sleep. All because there was NO WAY to cut the little devils OFF for a patently false alarm. Of course, getting that one taken care of was followed by a merry chase to get the OTHER FIVE alarms in the house yanked out. Fortunately, they were on shorter ceilings...
Not knowing that the recent humidity increase had caused this, the next day I reinstalled them all...because one wants their house and loved ones protected by smoke detectors, right? Right? Well, one does...except I had to repeat that adrenaline-charged experience AGAIN the next night. Then I left them off. ALL of them. Don't worry; we soon had a monitored alarm system installed, including smoke detectors...GOOD ones...and it was ten years before one of THOSE gave us any issues, and that was outside a bathroom, where higher local humidity is expected.
So, I'm no fan of cheap smoke detectors OR building codes that attempt to impose things "for my own good"... I guess this was more like "fire on the ceiling."
They could rig the button so the alarm was disabled for 5 minutes and needed to be repressed to disable it again. That way taping the button down wouldn't permently disable the smoke alarm. If fire fighters had to show up every time there was a false alarm, they would do something about it.
"Why don't these things have a button to shut off the alarm". Probably because the industry & the regulators decided that to add this function would DEFEAT the omnipresence of the device. Owing to people's inventiveness, MORE people than not would disable them w/ the push of a switch button. That WAS one of the "nice" features of the old, battery-only devices. They could be prominently displayed on ceilings throughout the structure, yet permanently disabled by omitting the 9-volt "transistor" battery.
Why don't these things have a button to shut off the alarm. I can't cook in my kitchen without setting off the smoke alarm. I then have to unplug the thing from the mains and remove the battery to shut it off. They just made a law in Maryland that the smoke alarms need to be replaced with ones that have non-removable rechargeable batteries. I think it's a plot.
In residential construction, depending on jurisdiction, "hard-wired" smoke detectors have been part of the building codes for over 10 years. Additionally, when these units are used, they MUST be wired in a "3-wire" circuit, where the two main conductors (BLK, WHT) are the source power & the thrird wire (RED) is the "communications" wire. IF a smoke detector on the first floor is activated, a signal is sent to ALL the others in the circuit, and they will begin to chime. This was one of the serious problems w/ the battery-only units of previous decades.
Furthermore, in many jurisdictions, the circuit for the smoke detectors MUST be on its own circuit, not on a shared line. Some jurisdictions require a separate small circuit breaker "box" tied directly to the main lines coming into the main C/B panel.
@MagFlux: My smoke alarms are all hard wired into the electrical system.
As I just replied to a previous comment: "Our smoke detectors are wired into the main house power supply -- the batteries are there for backup, so removing the batteries doesn't actually stop the alarm -- neither does cutting the circuit breakers, come to that, because then the batteries take over ... the only way to stop them is (a) cut the circuit breaker AND pull the batteries or (b) re-program them with a mallet"
@JoimFord: I'm curious as to why nobody thought to remove the batteries (temporarily) from the smoke detectors.
#1 Again, we are talking about my technology-challenged 18-year old son here -- he doesn't even know they have batteries in them.
#2 Our smoke detectors are wired into the main house power supply -- the batteries are there for backup, so removing the batteries doesn't actually stop the alarm -- neither does cutting the circuit breakers, come to that, because then the batteries would take over ... the only way to stop them is (a) cut the circuit breaker and pull the batteries or (b) re-program them with a mallet
A Book For All Reasons Bernard Cole1 Comment Robert Oshana's recent book "Software Engineering for Embedded Systems (Newnes/Elsevier)," written and edited with Mark Kraeling, is a 'book for all reasons.' At almost 1,200 pages, it ...