Smoke/CO detector lifespan?

Maybe they need to connect the smoke detectors to Wifi.. that way they can report their condition and alert the authorities and/or insurance company if they're not kept in top condition. Maybe use a MEMS sensor to detect various *kinds* of smoke, and report appropriately.

On a sunny day (Tue, 03 Sep 2013 09:55:12 -0700) it happened Don Y wrote in :

Fires can start in very unexpected places. I was amazed a while back when I did see a cloud of smoke coming from the window during the day in the living room: This was the culprit:

It had these laying in the window pane, just a glass ball and a little toy. Been there some time, cleaning put the toy in the focal point, the sun did the rest. Thought I had electronics covered.. but this ???

They already have wireless detectors. And, in commercial establishments, I suspect all of these alarm types are far more capable. (someone is *paid* to maintain them -- even if he/she doesn't see their value)

You can't legislate to cause people to *assume* (personal) responsibility (you can *impose* it, after-the-fact -- but that still doesn't mean they will "learn"). If people don't see the value in protecting *their* property, lives, etc. then crafting rules/regulations that try to force folks to be responsible isn't going to work, either.

Making a smoke detector that deliberately annoys its users to ensure the battery gets replaced isn't necessarily going to get the battery replaced!

I had a vehicle in the late 70's (?) that wouldn't start without the seat belts fastened (this was prior to current seat belt laws). Can you spell "nuisance"? I kept the seat belts buckled *behind* the driver/passengers and installed a N.O. pushbutton in series with the interlock switches in the buckles. Get in car; push button once (i.e., effectively unbuckling and then re-buckling all the belts); turn key; drive away. Repeat next time you need to start the car.

The "right" solution came when I learned the *value* of the belts and *wanted* to wear one (get to know a few friends with metal plates in their heads and your outlook changes real quick! :> )

Please read it again. It says "The law also requires that smoke alarms that are battery operated to have a battery with a minimum life of ten (10) years." That applies only to battery operated smoke alarms. AC powered alarms can apparently have a smaller backup battery.

My guess(tm) is that someone read the literature on wireless power meters and decided that if they can have a non-replaceable battery that can last 10 years, then the same can be done with a smoke alarm. Like all government inspired innovations, this one is going to fail when the smoke alarm actually goes off, and the high current from the loud annunciator rapidly depletes the battery.

Example of 10 year sealed smoke alarms. Prices in the $15-$25 range:

Of course. I snoozed through a lecture on fire safety a few years ago. I vaguely recall the speaker mention that they found far too many smoke alarms with dead batteries at fires. I'm guilty of much the same when I forgot and let my batteries run down for about 9 months before I remembered. I guess this is a way to take human error and unreliability out of the equation.

All this because nobody remembers to replace the battery. Maybe a good application for a coulomb counting power meter and a voice annunciator. "At the tone, you have two thousand three hundred and fifteen days left on your smoke alarm... ding". Human intelligence replaced by machine intelligence. Sigh.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

On a sunny day (Wed, 04 Sep 2013 10:46:56 -0700) it happened Jeff Liebermann wrote in :

Design so it burns down the pace when battery is almost empty,

Yup. Smoke alarms were a relatively new idea to me when they came out (having not "grown up" with them). So, I dealt with them

*reactively* -- when they started chirping The Dead Battery Minuet, I'd *find* a battery (from "stock on hand") to appease them.

It was only after having my chain yanked for many years that I adopted the *proactive* approach: replace the battery regularly BEFORE it starts annoying you! New Year's Day being as good a day as any other to remember to do this... And, to purchase *fresh* batteries in anticipation of this (instead of hoping that some

3 year old stock on hand is still up for the challenge!)

The chirping of this other detector, recently, was confusing! First, I assumed it was one of the 11 or 12 UPS's around the house either warning that it had switched to "battery backup mode"

*or* had detected a failed battery (seems they "chirp" from time to time -- just once or twice and then shut up). After wandering around trying to localize the chirp to one of these, I finally realized it was one of the smoke/CO detectors.

"Why the hell is it complaining *now*? I replaced the battery

8 months ago!" But, I dutifully replaced the battery (assuming that's what it was complaining about). This kept it quiet for a day or two. Then, it started up again.

"Hmmm, that battery can't be 'dead' -- unless YOU KILLED IT!" And, I tend to doubt that...

Of course, no one remembers what every possible alert means other than: chirp = attend to my needs horn = attend to YOUR safety! So, I had to dig out the manual to read what this particular alert meant. (I've never lived in a single house long enough for a smoke detector to "wear out")

Most "regulations" try to do exactly this. And, often fail because you can't force people to do things that they *should* want to do (for their own self-interests!).

Why do folks forget to perform maintenance on their vehicles?

Why do people smoke, drink-to-excess, use recreational drugs, etc.?

Why do people fail to "eat healthy", exercise, etc.?

Why do infants die from exposure in car seats (while mommy/daddy "just runs in" to bar/store/etc. "for a minute")?

Then they'll just find a way to silence the annunciator. Either by removing the unit entirely or jabbing a pencil through the "speaker cone".

"Paternalism" vs. "self responsibility". :<

A long time ago, I designed a "maritime autopilot". Tell the autopilot where you want to go (lat,lon) and it would get the boat to that location! I argued for adding an alarm to ensure the skipper would attend to the helm when the boat approached its destination (otherwise, I would dutifully keep turning the boat around each time it passed the destination -- I had no control over throttle -- nor did I have any awareness of what might be located in or near the waters in that area!).

Boss just shook his head: "We add a klaxon and the skipper will just cut the wires to it the first time it goes off!"

Yup, you cannot make anything foolproof cos fools are so damn foolish! And why is it when an alarm "goes off" it actually goes on? Probably need a new phrase for this phenomenon.

-Tom

And *creative*! :-/

Oh, that can start an **incredibly** long digression! ;-)

[PARK in the DRIVEway, DRIVE on the PARKway, etc.]

My personal favorite was my first visit to England: seeing a sign on a door that said "Way Out". And, being naive enough to ask "what's that (mean)?" :-/

Official wisdom suggests that you replace the battery at the beginning of daylight savings time (approx March 10). I think the logic is that most people will be too hung over on New Years day to successfully replace the battery without falling off the ladder.

Ummm... perhaps use a battery tester? Works nicely for alkaline but not so nicely for lithium.

Deferred maintenance is the politically correct term. People learned that from municipal governments, public utilities, and major corporations who have turned deferred maintenance into an art form. The GUM (great unwashed masses) simply follow their example.

Because the alternative forms of entertainment are dull, boring, and require too much brain power to handle.

Because junk food tastes good and you get more calories per dollar with junk food than with healthy food.

I hadn't heard that one.

A .22 caliber projectile is more convenient and gets immediate results.

In loco parentis.

True. I worked on a device with a similar alarm. The spec required that we shove some DC through the speaker to make sure that it was present. A short or open circuit would create an alarm condition, which caused all the lights and displays to flash. Given the choice of noise or flashing lights, most users chose the noisy alarm.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

We don't have Daylight Savings Time. :>

Hardly likely that it was "killed" in that short a period of time -- and still worked well enough to chirp, etc. More likely (as was then verified) that something else was causing the chirp!

Haven't seen the news stories in recent years?

Solution isn't to force this sort of behavior on the user but, rather, hope the user learns to *want* to behave that way. Or, finds a solution that *allows* him to be incompetent (e.g., hire someone to take on those responsibilities on your behalf!)

I recall a dental hygenist I had many years ago. After my first cleaning, she said "see you in 6 months". I asked if their office would be *calling* vs. *mailing* me a reminder. She said, "Neither. Their *your* teeth. If you don't want them, then you don't have to worry about making that appointment!" Interesting attitude! :>

That would void the 10 year (limited) warranty. It should burn the house down one day after the warranty expires. Shorting a lithium cobalt oxide battery (as in the Boeing Dreamliner) should do the trick. Think of this feature as an incentive for the timely replacement of the device.

No user serviceable parts inside.

I presume the next step is to collect recycling fees for handling throw away smoke alarms. Assuming everyone in California follows the new law, that would be a minimum of 12.4 million[1] new smoke alarms every 10 years assuming one per household. So, every year, over 1.2 million smoke alarms will hit the hazardous waste pile in California.

[1]

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

On a sunny day (Wed, 04 Sep 2013 12:07:10 -0700) it happened Don Y wrote in :

May be true for boats, dunno, but for airplanes, when the 'hammer' comes on, big bells, engine fire, whatever, I know! You can silence those, so provide an alarm reset button. But I guess the training is different for planes and boats... Here you even need a license for a rubber boat! But not for a big one once you get out to sea.... Logic Mr Spock, logic...