Recalled 'Nest Protect' Smoke Detectors Returning to Store Shelves Soon

[peterdevries]

I disagree... smoke detection sensors are now much more sensitive then they used to be. Wall mounted devices could be set to simply respond with a lower threshold then any of the existing ceiling mounted sensors and beat them to the punch. Since they would be easier to disable in the event of a false positive they could be set even more sensitively.

Sorry, but you are not thinking this through enough. Smoke detectors already have extremely low thresholds. Setting them lower and bringing them closer to the ground would make them susceptible to going off when you walk past with a sigaret or a pan of food. They are now already devices with an extremely delicate measurement setting. In addition, it would not help much, because smoke flows upward. You can't ensure that smoke from any source will touch the detector in time to be detected.

Think about the following scenario:

There is a fire in a room with a width of about 20 feet. The smoke from the fire goes straight upward and starts to accumulate at the ceiling. The smoke detector goes off as soon as the smoke reaches the detector. Even if the detector is 20 feet away it is only the ceiling that is covered by smoke and everyone can get out after being alerted.

Let's now look at your idea. The detector is at 3 feet above floor level and people are asleep in bed. There is a fire and smoke flows up. There is a smoke detector 20 feet away from the fire. The smoke starts accumulating at the ceiling, and hot air displaces cooler air, slowly filling up the room with smoke from above, until it reaches the smoke detector at 3 feet high. The detector starts beeping and wakes everyone up. Everyone that gets up will be standing from their waist upwards in smoke and will have to crawl outside.

There is no beating simple physics here. There is a solid reason why smoke-detectors are on the ceiling. It would be much easier to provide smoke detectors with a simple remote that you could press if there is a false alarm. Even then I'm questioning the necessity of this. Unless you live with a bad cook or a pyromaniac, the detector beeps only once every few years when the battery runs out. What problem are you trying to solve? Sincere question, not an attack.

 

[C DM]

I disagree... smoke detection sensors are now much more sensitive then they used to be. Wall mounted devices could be set to simply respond with a lower threshold then any of the existing ceiling mounted sensors and beat them to the punch. Since they would be easier to disable in the event of a false positive they could be set even more sensitively.

None of this negates the fact that you could still install one in the ceiling as well so in the end ceiling vs wall is a straw man argument. Electricians routinely install breakout boxes in the ceiling to later support light fixtures as well so this would be a very easy 'upgrade' and most likely only worth while putting in the kitchen.

What easily makes it a moot argument is that majority if construction/building codes simply call for smoke detectors on the ceiling. What someone might want or even argue for as far as placing them elsewhere becomes an excersise in futility since all of that doesn't matter given that there's simply no choice to begin with no matter what.

 

[groovyd]

Sorry, but you are not thinking this through enough. Smoke detectors already have extremely low thresholds. Setting them lower and bringing them closer to the ground would make them susceptible to going off when you walk past with a sigaret or a pan of food. They are now already devices with an extremely delicate measurement setting. In addition, it would not help much, because smoke flows upward. You can't ensure that smoke from any source will touch the detector in time to be detected.

Think about the following scenario:

There is a fire in a room with a width of about 20 feet. The smoke from the fire goes straight upward and starts to accumulate at the ceiling. The smoke detector goes off as soon as the smoke reaches the detector. Even if the detector is 20 feet away it is only the ceiling that is covered by smoke and everyone can get out after being alerted.

Let's now look at your idea. The detector is at 3 feet above floor level and people are asleep in bed. There is a fire and smoke flows up. There is a smoke detector 20 feet away from the fire. The smoke starts accumulating at the ceiling, and hot air displaces cooler air, slowly filling up the room with smoke from above, until it reaches the smoke detector at 3 feet high. The detector starts beeping and wakes everyone up. Everyone that gets up will be standing from their waist upwards in smoke and will have to crawl outside.

There is no beating simple physics here. There is a solid reason why smoke-detectors are on the ceiling. It would be much easier to provide smoke detectors with a simple remote that you could press if there is a false alarm. Even then I'm questioning the necessity of this. Unless you live with a bad cook or a pyromaniac, the detector beeps only once every few years when the battery runs out. What problem are you trying to solve? Sincere question, not an attack.

A few problems... being uglyness and inconvenience to turn off during false positives. Also the ability to signal each other via data over power protocol so that all alarms in the house are aware of each other and therefore don't need to be set so loud and may all turn each other on and off.

I am sure a wall mounted setup would detect a real fire just as fast if not faster as a ceiling mounted setup. Also, what prevents you from installing one in the ceiling as well if you think it really matters? I don't and wouldn't.

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What easily makes it a moot argument is that majority if construction/building codes simply call for smoke detectors on the ceiling. What someone might want or even argue for as far as placing them elsewhere becomes an excersise in futility since all of that doesn't matter given that there's simply no choice to begin with no matter what.

Laws change... and I don't imagine anyone patrolling my house to check where my fire detectors are. Still I think from an aesthetic point of view a fire detector enclosed in a standard outlet breakout box on the ceiling or not still makes sense. The Nest Protect is no less ugly then any older-school alarms out there.

 

[peterdevries]

A few problems... being uglyness and inconvenience to turn off during false positives. Also the ability to signal each other via data over power protocol so that all alarms in the house are aware of each other and therefore don't need to be set so loud and may all turn each other on and off.

It seems you miss some fundamental knowledge about how these systems work. Building regulations in most countries of the world currently require smoke detectors to be connected to enable switching off etc. And those same regulations require smoke detectors to be on the ceiling.

In addition insurances decrease their coverage if smoke detectors are installed incorrectly (i.e. on the wall) or absent. These laws will not change because in general there is little consumer inconvenience associated with smoke detectors located on the ceiling and the laws of thermodynamics will not change.

I am sure a wall mounted setup would detect a real fire just as fast if not faster as a ceiling mounted setup.

Again, read my previous post and ask a physics professor if you don't trust my judgment. You are wrong about this. Detectors don't detect fire but smoke.

Also, what prevents you from installing one in the ceiling as well if you think it really matters? I don't and wouldn't.

You are mistaken. The entire world doesn't think it matters to install them on the ceiling. We KNOW it matters.

 

[groovyd]

It seems you miss some fundamental knowledge about how these systems work. Building regulations in most countries of the world currently require smoke detectors to be connected to enable switching off etc. And those same regulations require smoke detectors to be on the ceiling.

In addition insurances decrease their coverage if smoke detectors are installed incorrectly (i.e. on the wall) or absent. These laws will not change because in general there is little consumer inconvenience associated with smoke detectors located on the ceiling and the laws of thermodynamics will not change.



Again, read my previous post and ask a physics professor if you don't trust my judgment. You are wrong about this. Detectors don't detect fire but smoke.



You are mistaken. The entire world doesn't think it matters to install them on the ceiling. We KNOW it matters.

Guess you completely ignored the part about me not caring what today's laws require. Or the part about being able to install an electrical breakout box detector in the ceiling as well... If you aren't going to read anything I write except the 1 part you disagree with then what's the point?

 

[C DM]

Guess you completely ignored the part about me not caring what today's laws require. Or the part about being able to install an electrical breakout box detector in the ceiling as well... If you aren't going to read anything I write except the 1 part you disagree with then what's the point?

Given that it doesn't make a difference whether you or anyoe else cares or not since that doesn't affect or change the reality (or laws of nature), this whole part of it, once again, is a completely moot discussion.

 

[peterdevries]

Guess you completely ignored the part about me not caring what today's laws require. Or the part about being able to install an electrical breakout box detector in the ceiling as well... If you aren't going to read anything I write except the 1 part you disagree with then what's the point?

On the contrary. I read your whole post, but I will indulge you and comment on each point that you made.

This whole discussion started when you mentioned that smoke detectors should be installed in generic light switches or boxes on the wall. You can ignore laws (physics or legal) all that you want and install smoke detectors on your floors and walls and anywhere you like. The point is that you will endanger the people that you live with if you don't put your smoke detectors on the ceiling. Additional detectors on the wall will not increase safety as they will detect smoke later if the fire is not directly below that specific smoke detector. The laws and regulations that you would choose to ignore are there exactly to avoid people making uninformed decisions about the placement of their smoke detectors. These uninformed decisions will and have already cost lives. These regulations are not there because the government or building associations like the look of smoke detectors on ceilings.

Your other objection is that smoke detectors are ugly, but a simple google search will show that there are hundreds of design detectors that go beyond the simple disc shape design that everyone knows.

You also mention that smoke detectors should be connected to enable the signal to reach into other rooms and to switch them all off centrally. All modern smoke detector setups have this facility. My house has it. All smoke detectors are connected and turn on and off at the same time. You also seem to be concerned about false alarms and turning a smoke detector off. I wonder where this concern comes from. I have lived all my life in houses with smoke detectors. In all that time I can recall only 3 false alarms, which were easily turned off. That is once in every 10 years and my experience does not differ from anyone else I know. Even if you need to do it once every few months – is the difficulty of turning a ceiling mounted detector off really a reason to put your family or yourself in danger by placing detectors on the wall?

The last part is really important. You might not believe us, so go and check it independently. Your assumption that smoke detectors work as well on the wall as they do on the ceiling is incorrect.

I hope this addresses most if not all of the points you brought up. What you are suggesting makes no sense, is dangerous and you will find no self-respecting electrician supporting these ideas (I hope). As C DM said, this whole discussion is moot.

 

[groovyd]

Given that it doesn't make a difference whether you or anyoe else cares or not since that doesn't affect or change the reality (or laws of nature), this whole part of it, once again, is a completely moot discussion.

moot discussion because what i am suggesting is currently not according to code? lol... that was never a pre-requisite to the idea; however being moot discussion with 'you'? yes i completely agree

 

[C DM]

moot discussion because what i am suggesting is currently not according to code? lol... that was never a pre-requisite to the idea; however being moot discussion with 'you'? yes i completely agree

Seems like you are conveniently ignoring that there's a whole lot more to it than just that. But, yeah, seems like it's all moot anyway, as you said.

 

[groovyd]

Seems like you are conveniently ignoring that there's a whole lot more to it than just that. But, yeah, seems like it's all moot anyway, as you said.

agree... we are both conveniently ignoring everything the other says in proof of our own point

 

[peterdevries]

Seems like you are conveniently ignoring that there's a whole lot more to it than just that. But, yeah, seems like it's all moot anyway, as you said.

We are obviously trying to reason with a teenager here.

Let's just wait until he has had physics class in high school and pray that he hasn't figured out how matches work...

 

[MacFly123]

I hope so... I wish apple would of purchased Nest instead of Beats. It could of been their home automation "hobby".

would HAVE... could HAVE... Not OF!

 

[Eric E. Schmidt]

why go the specific appliance route when most devices rely on the general wiring of the building? to leapfrog competition in the home automation market apple could simply buy a company that supply switches, sockets and the like to contractors. that way all future builds and retrofits could be ihomes. beyond controlling switches and sockets, by adding a data interface like lightning to the sockets any compatible appliance could be controlled by the system.