They have a very small amount of radioactive material (~1.0 microcurie of the radioactive element americium-241) that is used as part of the detector, and it does what you’d expect it to do: it decays.
Consumer Reports can and should do better being a bit more verbose for correctness.
A lot of them these days are photoelectric. They have a “light sealed” chamber (basically vented in such a way that ambient light doesn’t have a path into the chamber but “smoke” does (well smoke, dust and other airborne particulate that is carried in the air)). Instead in the chamber you have a light source and detector. Light is emitted from the source, reflects of the side of the detector and onto the detector. (Actually, thinking about it, I’m sure that they can also work “the other way round”, so instead of particulate blocking the light, lowering the detection levels, they can configured so the light source isn’t pointing at the detector and use the reflectivity of “smoke” to relect light onto the detector. But you get the idea. It’s been far too long since I’ve taken one apart, time to order another for fun. Anyways back to the post)
Dedicated ICs for this purpose can detect the slight lowering of light detected over time by the receiver as dust accumulates instead the chamber and adjust its trigger levels accordingly.
Removes the need for need for the scary radiation source warning label, removes the issue with the radiation source decaying over time and I’m sure comes with that lovely side effect of lowering the BOM cost.
Even though LEDs also decay, as it’s duty cycle is no where need 100% and is completely controlled by the IC I would expect the components in a photoelectric smoke detector to last much much longer than 10, but mine still came with (iirc) a 10 year expiry date on them. I would say because it’s a safety device, an abundance of caution is applied so other things ageing out have to be considered too (like the power supply caps)
Big Clive has taken these apart many a time. If this one doesn’t cover the operation of them, just search for smoke alarm on his channel and I’m sure it won’t take long before find one where he “tears down” the smoke detection chamber of an photoelectric version. https://youtu.be/uzKAZCKjpU8
No idea off the top of my head on how heat detectors (best near your kitchen so your toast doesn’t trigger them) work as personally I’ve never taken one of them apart (yet).
> Could I build my own out of a Pi and some scavenged components? Sure – but I can’t be bothered
More importantly, no insurance company will cover costs from a fire if they find out that you had a self built smoke detector which didn't pass standard quality checks. I think in the UK landlords must do a yearly smoke detector check as part of home owner regulation so a self built device might have failed at that point as well.
A workaround could be a completely separate device placed next to a standard, certified smoke alarm that just listens for the alarm. That'll cover the "remote alerts" part at least.
That was my solution as well. I have required smoke detectors connected to powerline 1 per 60m2 or so and then have multiple Heiman zigbee detectors, connected to Home Assistant.
> More importantly, no insurance company will cover costs from a fire if they find out that you had a self built smoke detector which didn't pass standard quality checks.
Is this a thing? Where?
Are there similar things for burglar alarms where your insurance doesn’t pay or has a more expensive premium because of lacking alarm systems?
Making a fire alarm smart should never affect the normal functionality. They should of course always be certified the same way. One thing that could be worse is battery time, especially for high power wireless like 802.11, but a workaround for that could be to have two separate batteries and let it fail to a dumb alarm when the IoT battery is dead.
Please consider the US market for future iterations (and a SIM socket if it’s a reasonable price on the BOM). I believe Twilio even offers a global SIM with reasonable IoT data rate pricing.
It was more about space, it's small module inserted into that big detector. We would probably just make different module for US. Worldwide module is in planning stage after nb-iot takes off more widely.
I’ve read about all sorts of alarms (I don’t think smoke, but fire and other emergency alarms) running on things like ISDN before the term IoT ever existed
And I've worked on telemetry devices which had modem and could phone alarms and data to control room over landlines before there was any ISDN available. This was for city heating control. My company was upgrading this to mobile connectivity. Whole system earned it's worth after one pipe break, because operator could select area on map, turn off all flow to different devices with several clicks and they didn't have to use complicated freezing devices to fix pipe.
Make really irritating noise whenever something is wrong.
And exactly two definitions of wrong: smoke and low power.
The incorporation of convenience features entirely defeated the purpose of smoke detectors. It made them less likely to save lives.
There are still IOT smoke detectors in the commercial space for air ducts. And instead of noise, they signal a monitored central station in facilities in working relationships with the local fire service. Hospitals for example.
That's not your house.
The limited life expectancy of smoke detectors created an attractive recurring purchase model for Nest. It over-ruled life safety effectiveness. I suspect, but have no evidence beyond circumstantial, that lawyers, regulators, and insurers all said things that made financial accountants remodel projections.
I like the second kind of wrong. My smoke sensors start to make random short bleeps. I have about 10 of them in our house. Usually it will take at least annoying 15 minutes to locate the culprit.
Don't they have a LED to indicate low power? I don't know much about smoke detectors, but I'd imagine they'd have a LED on at all times to indicate that they're working.
I disagree. My dumb detectors started false positives after just a few years. Their mute/silence buttons didn't work so burnt toast meant two minutes of screeching. No options for remote alerts (without external smart hardware). Batteries would only fail at night even after a few years. Or dust? Or carbon monoxide? Never knew, because the beeps were a terrible form of communication.
Smoke detectors SHOULD have some safe, reliable smart technology. All my Protects have outlasted the simple Kiddes.
The Venn diagram of people who don't change batteries, can't reliably make toast, and want a feature rich smoke alarm is non-empty based on this thread.
Well, you could have a mains powered rechargable battery (or supercapacitor) backed detector.
Then again, it better be designed so that the sensor part is replaceable and it fails loud.
(Though neither supercapacitor nor nickel-* cells are very expensive, we put them in random MP3 players for $10 a pop.)
The half-life of commodity rechargeable batteries is significantly less than the half-life of Americium.
And people who don't proactively replace smoke alarm batteries are unlikely to proactively change the alarms...changing out an alarm is a bigger job than changing batteries.
I seem to live in some sort of weird temporal anomaly where things last longer than they should.
My smoke detector seems to be working fine, judging from its propensity to go off when I do something in another part of the house that emits smoke, even though it has been here for the 14 years I've owned this house.
The security light over my garage, which is controlled by a light sensor and is on overnight every night, is still on the same bulb it was on when I moved in. Figure an average of 10 hours a day for 14 years and that is 51000 hours.
I'm not sure exactly what kind of bulb it is, other than it is not LED, but all the other possibilities (LPS, HPS, mercury vapor, florescent, metal-halide) should be somewhere in the 12000-24000 hour lifespan range.
My washing machine and dryer are also the ones that came with the house, and are still working fine. They aren't very fancy--if a time warp landed then in a house in the 1960s no one would realize they are from the future--but they get the job done. The washing machine was made in August 2003 and the dryer April 2004 [1].
The heat pump compressor is around 40 years old. I've been told that is about twice as long as they are expected to last.
Other things that came with the house that are still going strong are the well pump, water heater, and all the major kitchen appliances except the fridge. The fridge died a couple years ago or so.
[1] Probably. GE recycles year codes, so all I can say for certain is that the washer was made in one of {2015, 2003, 1991, 1979, or 1949} and the dryer in {2016, 2004, 1992, 1980, or 1950}.
Yeah, I will. I wasn't suggesting that I should continue using mine past 10 years (looking at the datestamp on it, it was actually made 3 years before I bought the house, so it is 17 years old). Just noting that many things around my house seem to be working well past when they should.
Looks like Walmart even has one that is the same brand (First Alert) as my current one and appears to use a compatible mounting plate for $7.67, so should be an easy replacement.
> They have a lifespan based on radioactive decay of the detector.
Americium-241 has a half-life of 432.2 years, while the recommendation is to replace a detector after only 10 years. But only 1.6% of the Am-241 has decayed after 10 years, so there must be other reasons for the short life span.
If your smoke alarm is faulty you should replace it. Unlike most hardware, faulty smoke alarms can directly lead to the death of yourself or family. It's the one form of tech that I 100% replace when any problems occur.
There is no situation where you should accept or ignore a faulty smoke alarm.
I dunno, I don’t see a problem with progressive enhancement of a dumb device: Clearly, don’t control the screecher with a web-connected microcontroller. But if it’s a totally standard dumb fire alarm that also outputs a voltage to a microcontroller that sends an alert to your smart home platform of choice? I don’t see the downside. And if it has a 90% chance of alerting you that your fire alarm has gone off when you’re out of earshot of the irritating noise? Why not?
The reason it’s a fucking dumb idea is in no small part because it doesn’t conform to our ordinary pattern recognition of really fucking dumb ideas.
The Nest could be disabled by waving at it...It was a feature.
There are smoke alarms you can connect to a central alarm panel. Alarm panels that can be monitored remotely. And monitoring services that will call you when there is an alarm.
The difference is each element prioritizes life safety by conforming to life safety standards.
An important dimension of these standards is saving the lives of firefighters. When everyone is out of the structure they don’t need to go into an actively burning building.
If you are out of earshot of a smoke alarm, what can you do besides turn it off?
Home IoT devices are not known for their security. Nor are they known for long term support. The article itself demonstrates that...
A smoke alarm is not a consumer is always right device. There’s nothing stopping an Alexa skill that responds to the noise of a smoke alarm with a text to your phone.
And people don't reason well about fire when it occurs.
Your second alternative ought to be the first. But it isn't what you thought of first. That's normal when it comes to structures on fire.
Why "come home" is before calling the fire service is because normal inclination is to want to save building contents from burning. On the way there, you would make a mental list. Arrive ready to go inside. It's how we are wired.
Smoke alarms are the way they are not based on theory.
They are the way they are based on experience. Not lay experience. Professional experience of fire fighters counting corpses and conducting after action debriefings and writing reports.
A person will run out of fingers and toes counting all the obviously bad ideas that contributed to the thirty six fatalities. And counting all the individuals who poorly assessed the life safety risk for the sake of convenience and lifestyle.
The Nest sounds a loud alarm - that would wake people up and get them out of the house.
If I got an alert, I could call my partner and make sure they were already safe.
If I was at home and had my headphones on, my phone would vibrate. That will get my attention in a way that a traditional alarm won't.
I also hooked my Nest up to my Lifx bulbs - so they'll all turn on when an alert sounds. Again, pretty good at getting my attention and helping me see.
I'm not really sure why you're so against the idea. They do everything a traditional alarm does - but they add a few features which I find quite useful. To reiterate - a Nest Protect is a traditional smoke alarm, but it _also_ has WiFi.
As I said in my blog post, I wondered why other companies don't sell them. If, as you say, we're hard-wired to want these sort of "useless" things - surely there should be a market?
I have an interest in life safety. Partially by professional experience and training. Personally from having knocked on a neighbor’s door because their house was on fire.
Family member babysitting three kids. Living room filling with smoke. I said “the house is on fire. You need to get out.”
The adult had lit a wood fire in a gas fireplace. And was trying to put out the flames that were showing at the mantel.
Fires burn upward. It had burned down the chimney that far. I’d seen the flames outside. That’s why I said “stop the car.”
He was still not quite ready to admit defeat. So I directed the kids and they went outside.
I said, “we need to go.” And turned. Fortunately they followed.
We were all across the street waiting for the fire department. My beloved called 911 from the car when I got out to knock.
That fire department has a five minute response time.
Before they arrived the youngest child mentioned their turtle. The adult started past me saying they would get some clothes too.
I stuck out my arm and said “it’s not worth dying for.”
They hesitated for a moment and then the attic flashed over with back draft. And the sound was a whoosh.
And a minute or two later the fire fighters arrived.
I only knew the psychology from professional experience. I learned from an old fire inspector named Roy who patiently explained how stupid I was in trying to design an ethane distribution system for a research lab by telling me some of the things he had seen people do.
As cool as all those things you want sound, they are not as cool as not dying.
I didn’t want Roy to tell me my design was dumb. But he did and I am thankful for it.
You wondered where the devices went. I told you. It’s unfortunate you don’t recognize the difference between opinion and informed opinion. Particularly since you write a relatively popular blog...popular because it contains informed opinions.
This is not among them.
And unlike others the consequences are potentially lethal.
Fun fact: when I knocked on the door, one or more smoke alarms were going off.
> None of those gets anyone out of the house.
> None increases life safety.
Well, if your neighbor happens to have an adjoining home (for instance living in an apartment two floors above you) then contacting them could be life saving.
If you live in a multi floor apartment building without fire sprinklers, that’s a bigger problem. Fire sprinkler systems not only put out fires, they have a flow alarm that goes through an alarm panel and signals a qualified monitoring station...sometimes private, sometimes the local fire service.
Also at the alarm panel additional alarms are triggered in the building. Importantly it’s not a roll your own system. It’s tested and inspected and designed to fail safe.
Do you have examples of Nests failing more frequently than normal alarms? The connectivity is not useless and is one of the reasons I bought them, 12 of them for my house. If you live in even a medium sized house you have a lot of rooms such that having ALL the alarms go of telling you the specific room the smoke is in can make a huge difference.
Not to mention that these alarms do both types of smoke/fire and carbon monoxide all in one.
When a smoke alarm goes off, it’s telling you to get out of the house. The Nest design encourages opening an app on your iPhone instead. A smartphone has many uses but it is not a practical fire extinguisher.
Each of its convenience features for non-critical events is potentially a deadly distraction when life is a matter of seconds. It’s the smoke that usually kills.
> A smoke detector has exactly one function. Make really irritating noise whenever something is wrong.
No that’s one of two functions. The other one is letting me know if there is something burning even when I’m not home. It’s not nearly as important as the first job and a device should never do the first job worse because of it. But it can come in handy.
A good connected fire alarm can do all kinds of things like closing all windows or work as a siren for a home alarm.
In no situation should they ever be dependent on a cloud service, not even for “additional” features beyond the beep-when-there-is-fire function.
So long as the alarm is a normal dumb smoke alarm and any additional features is on top of that, it’s fine.
If you can screw it up, or the smart features adds any risk - it’s a bad product.
I’m not arguing that no connected alarms are bad. I’m arguing that It’s possible, and easy, to make a connected alarm that is no worse than a dumb one
.
That’s a completely different argument. It’s trivial to make a lousy product. Even easier with a product that tries to be smart. That doesn’t make it a fundamental law that it has to be that way.
I don’t doubt that Nest products are useless, their smart features require an internet connection which is a clear sign of trash in any home product.
Taking a dumb alarm and putting a radio or other connection on it doesn’t (shouldn’t) affect the functionality. These alarms also existed since forever for larger buildings. No one would argue that they were less reliable than dumb alarms.
Alarms for life safety in large buildings are traditionally hard wired with bespoke wires that have been tested and carry distinct markings. The system has emergency power which is also designed, tested and listed for the specific use.
The system is designed by a licensed engineering, installed by a specialty contractor, and inspected by the authority having jurisdiction.
Commercial construction is not just like your house only bigger.
A WiFi connected smoke alarm is full of incidental complexity. That makes it inherently less suited to function than the simpler design.
If there is any incidental complexity, a single additional failure mode of the core alarm functionality then the product is a bad product and shouldn’t even be approved.
Building these correctly is as simple as building a dumb alarm and adding a second product in the enclosure (a radio link). If built correctly, nothing in the smart bit can sabotage the dumb bit. For example, it can have its own power supply. Or be completely isolated from the alarm.
Others in this thread have described how they put an esp8266 or similar right next to their dumb alarm and have it report when the alarm goes off by detecting the sound. This has zero additional failure modes!
Nest Protects are still around and are amazing. So much better than the garbage Kiddes I had before (a working mute/silence button? What a concept!). The self tests and green Ok light at night are comfort boosters. And the voice announcement of the alarm level and location are great features.
I got a zwave product that you mount next to your normal smoke detector. It listens for the alarm. When it hears it, it sends a zwave notification. Works great!
I also have laser particulate sensors hooked to esp8266s for dramatically higher resolution smoke/air quality detection. They go over Mqtt to home assistant for graphing, automations, etc.
433MHz coupled wireless smoke detectors are about as cheap as ones without. And their signal can be intercepted by a cheap Rflink device: http://www.rflink.nl/blog2/devlist
Granted they are not as fancy as a Nest, but you can buy 5 of these for the price of 1 Nest. And the Nest's aren't flawless either. I've had to reconnect 2 of the 3 Nest's at my parent house multiple times now and also a Google account is now required.
The only thing I would be looking for out of a smart smoke detector is remote notification and I already achieve this using my Wyze cameras. They are set to listen for smoke and carbon monoxide alarms. They will notify me if detected. The notification also triggers other actions such as all the lights in the house being turned on.
Given how many stories there are of IOT devices being hijacked for bitcoin mining or hacked in other ways I am extremely grateful that my smoke alarms are dumb as bricks.
Just have something In the room listen for the horrific screeching of a fire alarm. Then have it send you an sms or whatever. No need to cal it a “fire” anything and no regulatory hurdles to overcome.
As technology propagates into everything one would be wise to comprehend the management of such devices that are connected regardless of the function. Significant home automation adoption is coming and some have decades of experience in building those changes. Where there is smoke usually fire leads.
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[ 4.4 ms ] story [ 141 ms ] thread> The life expectancy of smoke alarms is generally 10 years, after which point their sensors can begin to lose sensitivity.
Every website says they should be replaced every 7-10 years anyways, regardless of their smart-ness.
Consumer Reports can and should do better being a bit more verbose for correctness.
Dedicated ICs for this purpose can detect the slight lowering of light detected over time by the receiver as dust accumulates instead the chamber and adjust its trigger levels accordingly.
Removes the need for need for the scary radiation source warning label, removes the issue with the radiation source decaying over time and I’m sure comes with that lovely side effect of lowering the BOM cost.
Even though LEDs also decay, as it’s duty cycle is no where need 100% and is completely controlled by the IC I would expect the components in a photoelectric smoke detector to last much much longer than 10, but mine still came with (iirc) a 10 year expiry date on them. I would say because it’s a safety device, an abundance of caution is applied so other things ageing out have to be considered too (like the power supply caps)
Big Clive has taken these apart many a time. If this one doesn’t cover the operation of them, just search for smoke alarm on his channel and I’m sure it won’t take long before find one where he “tears down” the smoke detection chamber of an photoelectric version. https://youtu.be/uzKAZCKjpU8
No idea off the top of my head on how heat detectors (best near your kitchen so your toast doesn’t trigger them) work as personally I’ve never taken one of them apart (yet).
More importantly, no insurance company will cover costs from a fire if they find out that you had a self built smoke detector which didn't pass standard quality checks. I think in the UK landlords must do a yearly smoke detector check as part of home owner regulation so a self built device might have failed at that point as well.
Is this a thing? Where?
Are there similar things for burglar alarms where your insurance doesn’t pay or has a more expensive premium because of lacking alarm systems?
Making a fire alarm smart should never affect the normal functionality. They should of course always be certified the same way. One thing that could be worse is battery time, especially for high power wireless like 802.11, but a workaround for that could be to have two separate batteries and let it fail to a dumb alarm when the IoT battery is dead.
https://ferguson-digital.eu/produkt/gsm-smoke-detector-fs2sd...
A smoke detector has exactly one function.
Make really irritating noise whenever something is wrong.
And exactly two definitions of wrong: smoke and low power.
The incorporation of convenience features entirely defeated the purpose of smoke detectors. It made them less likely to save lives.
There are still IOT smoke detectors in the commercial space for air ducts. And instead of noise, they signal a monitored central station in facilities in working relationships with the local fire service. Hospitals for example.
That's not your house.
The limited life expectancy of smoke detectors created an attractive recurring purchase model for Nest. It over-ruled life safety effectiveness. I suspect, but have no evidence beyond circumstantial, that lawyers, regulators, and insurers all said things that made financial accountants remodel projections.
Smoke detectors SHOULD have some safe, reliable smart technology. All my Protects have outlasted the simple Kiddes.
Making them $200 a pop makes this less likely.
They are safe reliable technology. Convenience features make them less so.
Because we live in a world where some people can’t even operate a toaster.
You could replace the cheap detector part and keep the expensive smart part.
Of course the manufacturers would rather have you buy the smart part over and over again. Sounds like a great idea and now they have nothing.
The feature richness is a scam though.
And people who don't proactively replace smoke alarm batteries are unlikely to proactively change the alarms...changing out an alarm is a bigger job than changing batteries.
A smoke alarm is not a consumer product.
My smoke detector seems to be working fine, judging from its propensity to go off when I do something in another part of the house that emits smoke, even though it has been here for the 14 years I've owned this house.
The security light over my garage, which is controlled by a light sensor and is on overnight every night, is still on the same bulb it was on when I moved in. Figure an average of 10 hours a day for 14 years and that is 51000 hours.
I'm not sure exactly what kind of bulb it is, other than it is not LED, but all the other possibilities (LPS, HPS, mercury vapor, florescent, metal-halide) should be somewhere in the 12000-24000 hour lifespan range.
My washing machine and dryer are also the ones that came with the house, and are still working fine. They aren't very fancy--if a time warp landed then in a house in the 1960s no one would realize they are from the future--but they get the job done. The washing machine was made in August 2003 and the dryer April 2004 [1].
The heat pump compressor is around 40 years old. I've been told that is about twice as long as they are expected to last.
Other things that came with the house that are still going strong are the well pump, water heater, and all the major kitchen appliances except the fridge. The fridge died a couple years ago or so.
[1] Probably. GE recycles year codes, so all I can say for certain is that the washer was made in one of {2015, 2003, 1991, 1979, or 1949} and the dryer in {2016, 2004, 1992, 1980, or 1950}.
Statistically, you are a very very lucky human.
The replacement cycle of a smoke alarm has a built in safety factor because it was designed by engineers.
If your life was hanging by a rope, you're betting on it's absolute strength not it's rated load.
Smoke alarms are ten bucks a pop at Walmart. You can pick up a CO alarm and a box of waffles while you are there.
Looks like Walmart even has one that is the same brand (First Alert) as my current one and appears to use a compatible mounting plate for $7.67, so should be an easy replacement.
Americium-241 has a half-life of 432.2 years, while the recommendation is to replace a detector after only 10 years. But only 1.6% of the Am-241 has decayed after 10 years, so there must be other reasons for the short life span.
There is no situation where you should accept or ignore a faulty smoke alarm.
The Nest could be disabled by waving at it...It was a feature.
There are smoke alarms you can connect to a central alarm panel. Alarm panels that can be monitored remotely. And monitoring services that will call you when there is an alarm.
The difference is each element prioritizes life safety by conforming to life safety standards.
An important dimension of these standards is saving the lives of firefighters. When everyone is out of the structure they don’t need to go into an actively burning building.
If you are out of earshot of a smoke alarm, what can you do besides turn it off?
Home IoT devices are not known for their security. Nor are they known for long term support. The article itself demonstrates that...
A smoke alarm is not a consumer is always right device. There’s nothing stopping an Alexa skill that responds to the noise of a smoke alarm with a text to your phone.
Come home. Or call the fire brigade. Or ask a neighbour to check. Or log into your home cameras to check for smoke.
None increases life safety.
And people don't reason well about fire when it occurs.
Your second alternative ought to be the first. But it isn't what you thought of first. That's normal when it comes to structures on fire.
Why "come home" is before calling the fire service is because normal inclination is to want to save building contents from burning. On the way there, you would make a mental list. Arrive ready to go inside. It's how we are wired.
Smoke alarms are the way they are not based on theory.
They are the way they are based on experience. Not lay experience. Professional experience of fire fighters counting corpses and conducting after action debriefings and writing reports.
An HN related example, http://www2.oaklandnet.com/oakca1/groups/ceda/documents/repo...
A person will run out of fingers and toes counting all the obviously bad ideas that contributed to the thirty six fatalities. And counting all the individuals who poorly assessed the life safety risk for the sake of convenience and lifestyle.
Again, it's how we are wired.
And why smoke alarms have to be required by law.
If I got an alert, I could call my partner and make sure they were already safe.
If I was at home and had my headphones on, my phone would vibrate. That will get my attention in a way that a traditional alarm won't.
I also hooked my Nest up to my Lifx bulbs - so they'll all turn on when an alert sounds. Again, pretty good at getting my attention and helping me see.
I'm not really sure why you're so against the idea. They do everything a traditional alarm does - but they add a few features which I find quite useful. To reiterate - a Nest Protect is a traditional smoke alarm, but it _also_ has WiFi.
As I said in my blog post, I wondered why other companies don't sell them. If, as you say, we're hard-wired to want these sort of "useless" things - surely there should be a market?
I hope you have a calm and pleasant weekend.
Family member babysitting three kids. Living room filling with smoke. I said “the house is on fire. You need to get out.”
The adult had lit a wood fire in a gas fireplace. And was trying to put out the flames that were showing at the mantel.
Fires burn upward. It had burned down the chimney that far. I’d seen the flames outside. That’s why I said “stop the car.”
He was still not quite ready to admit defeat. So I directed the kids and they went outside.
I said, “we need to go.” And turned. Fortunately they followed.
We were all across the street waiting for the fire department. My beloved called 911 from the car when I got out to knock.
That fire department has a five minute response time.
Before they arrived the youngest child mentioned their turtle. The adult started past me saying they would get some clothes too.
I stuck out my arm and said “it’s not worth dying for.”
They hesitated for a moment and then the attic flashed over with back draft. And the sound was a whoosh.
And a minute or two later the fire fighters arrived.
I only knew the psychology from professional experience. I learned from an old fire inspector named Roy who patiently explained how stupid I was in trying to design an ethane distribution system for a research lab by telling me some of the things he had seen people do.
As cool as all those things you want sound, they are not as cool as not dying.
I didn’t want Roy to tell me my design was dumb. But he did and I am thankful for it.
You wondered where the devices went. I told you. It’s unfortunate you don’t recognize the difference between opinion and informed opinion. Particularly since you write a relatively popular blog...popular because it contains informed opinions.
This is not among them.
And unlike others the consequences are potentially lethal.
Fun fact: when I knocked on the door, one or more smoke alarms were going off.
Well, if your neighbor happens to have an adjoining home (for instance living in an apartment two floors above you) then contacting them could be life saving.
Also at the alarm panel additional alarms are triggered in the building. Importantly it’s not a roll your own system. It’s tested and inspected and designed to fail safe.
Not to mention that these alarms do both types of smoke/fire and carbon monoxide all in one.
Each of its convenience features for non-critical events is potentially a deadly distraction when life is a matter of seconds. It’s the smoke that usually kills.
I disagree
> A smoke detector has exactly one function. Make really irritating noise whenever something is wrong.
No that’s one of two functions. The other one is letting me know if there is something burning even when I’m not home. It’s not nearly as important as the first job and a device should never do the first job worse because of it. But it can come in handy.
A good connected fire alarm can do all kinds of things like closing all windows or work as a siren for a home alarm.
In no situation should they ever be dependent on a cloud service, not even for “additional” features beyond the beep-when-there-is-fire function.
That you disagree by this rationale is why it is a dumb idea.
I mean that it’s not a worse product because it’s connected (No smoke alarm should be worse than a dumb one at that job).
And since there can be benefits it’s not a bad idea.
Obviously if it has shorter lifespan, can fail in some way a dumb alarm couldn’t, then it’s not a good product.
By design.
It was a differentiation feature used for its marketing.
There are exactly zero good ideas for user configuration of a smoke alarm.
If you can screw it up, or the smart features adds any risk - it’s a bad product.
I’m not arguing that no connected alarms are bad. I’m arguing that It’s possible, and easy, to make a connected alarm that is no worse than a dumb one .
That’s a completely different argument. It’s trivial to make a lousy product. Even easier with a product that tries to be smart. That doesn’t make it a fundamental law that it has to be that way.
I don’t doubt that Nest products are useless, their smart features require an internet connection which is a clear sign of trash in any home product.
Taking a dumb alarm and putting a radio or other connection on it doesn’t (shouldn’t) affect the functionality. These alarms also existed since forever for larger buildings. No one would argue that they were less reliable than dumb alarms.
The system is designed by a licensed engineering, installed by a specialty contractor, and inspected by the authority having jurisdiction.
Commercial construction is not just like your house only bigger.
A WiFi connected smoke alarm is full of incidental complexity. That makes it inherently less suited to function than the simpler design.
Building these correctly is as simple as building a dumb alarm and adding a second product in the enclosure (a radio link). If built correctly, nothing in the smart bit can sabotage the dumb bit. For example, it can have its own power supply. Or be completely isolated from the alarm.
Others in this thread have described how they put an esp8266 or similar right next to their dumb alarm and have it report when the alarm goes off by detecting the sound. This has zero additional failure modes!
Its good because otherwise a fire could start in one section of the house without me waking up for example.
I just enable Alexa to listen for smoke alarms and send me a notification when I am away.
I also have laser particulate sensors hooked to esp8266s for dramatically higher resolution smoke/air quality detection. They go over Mqtt to home assistant for graphing, automations, etc.
Granted they are not as fancy as a Nest, but you can buy 5 of these for the price of 1 Nest. And the Nest's aren't flawless either. I've had to reconnect 2 of the 3 Nest's at my parent house multiple times now and also a Google account is now required.
Soon...