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Discussion Starter · #1 ·
Right now I have Kidde hardwired detectors...

I know the difference between ionizing and photoelectic and why you might want to detect smoldering vs fast fires..

That said, does anyone make a combination Photo / Ion / CO detector? I thought Kidde made one but I can't seem to find it. I would like to put them in the bedrooms to kill a few code issues at once.
 

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Discussion Starter · #3 ·
You don't need CO detectors in bedrooms. Only in foyers/stairwells.
that's not what our local's are requiring... must have one inside bedroom or within 10 ft outside.. already got flagged by the inspector for this.. trying to finish up a bedroom remodel... :plain:
 

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I think it's new as well. I bought my house about 10 years ago and it required smoke detectors as Pharon stated... basement, stairways, foyers and linked together on an electrical circuit (not just battery, and if one goes off they ALL go off).

My friend just sold their house, and the fire department must've updated it as smoke detectors won't do anymore must be combination CO/Smoke units and they had to install it in not only the locations mentioned but outside the bedrooms too. There's a bedroom in my house that doesn't have a smoke detector outside it, I'm also looking into updating my detectors with Smoke/CO detectors and adding that one lacking outside one of the bedrooms. I don't know if it's a local thing or not that mine have to all be connected and must be 120v (but they have 9v batteries in them too), and someone said it has to share a circuit with something else encase the breaker trips you'll be more likely to notice it than if they're on their own circuit. However, I don't think it goes that far mine are on their own circuit/breaker.
 

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If the work isn't being inspected, all you need is one combo alarm with co detection in the system on the same level as fuel burning appliances.

All the alarms will activate when monoxide is detected.

Some of the codes are stupid and you don't need to follow them unless you're dealing with permits.

Also, dual sensor alarms aren't as good as once thought. I was reading that only the entire unit as a whole has to pass UL tests, not the individual sensor circuits. So the manufacturer can make the ionization sensor less sensitive to prevent false alarms, give it no advantage over a photo-electric alarm or vice versa.

With two sensors you have more to go wrong, more false alarms.

For most areas you're most likely to have a smoldering fire rather than flaming and smoke from smoldering fires kills much more so than flames. I would only use ionization to monitor a basement or workshop full of flammable liquids or to monitor a hall outside bedrooms with photo-electric units in the bedrooms.
 

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My friend just sold their house, and the fire department must've updated it as smoke detectors won't do anymore must be combination CO/Smoke units and they had to install it in not only the locations mentioned but outside the bedrooms too.
It's crazy to force a owner to incur an expense like that; what ever happened to buyers doing their due diligence?
 

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"
The UL Standard 217, “
Single and Multiple Station Smoke Alarms”
allows for dual
sensor alarms so long as the each sensor is
primarily a smoke sensor and the design meets
the Standard [6]. The alarm logic is an {O
R}-type such that the alarm is activated if
either the photoelectric sensor
or ionization sensor alarm thres
hold is met. The individual
sensor sensitivities are not tested separatel
y. Therefore, manufacturers have the freedom
to set each sensor’s sensitivity separately. Sinc
e an individual sensor can be set to meet
all current sensitivity standards, it is not obvious what ove
rall benefit is achieved from a
dual alarm with an additional se
nsor technology that could be
more or less sensitive than
what would be found in a standalone unit em
ploying such a sensor. Additionally, another
potential benefit of a dual se
nsor alarm may be realized by
adjusting each sensor’s alarm
threshold to reduce nuisance alarms. Thus, the
sensitivity of each sensor factors into the
overall performance of a dual alarm." http://fire.nist.gov/bfrlpubs/fire09/PDF/f09006.pdf
 

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From what I understand, this smoke requirement can be found in NFPA 72, Chapter 11. But that's only for where you need smokes. I'm not sure where the requirement is for CO detectors in that Code.
 

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If the work isn't being inspected, all you need is one combo alarm with co detection in the system on the same level as fuel burning appliances.

Some of the codes are stupid and you don't need to follow them unless you're dealing with permits.
Some of the worst advice I have ever seen on here, Even though some codes are stupid they still need to be followed.

Even if it is not being inspected, please still follow the codes. They are there for safety, especially when dealing with life and safety devices.
 

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Some of the worst advice I have ever seen on here, Even though some codes are stupid they still need to be followed.

Even if it is not being inspected, please still follow the codes. They are there for safety, especially when dealing with life and safety devices.
If I were "required" to install combo alarms in bedrooms, they'd literally be 3 feet from the combo in the hall. In that case, the code IS stupid and I wouldn't follow it either.
 

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Some of the worst advice I have ever seen on here, Even though some codes are stupid they still need to be followed.

Even if it is not being inspected, please still follow the codes. They are there for safety, especially when dealing with life and safety devices.
meh. Most houses don't even have interconnected alarms. Funny how everyone survived without the codes. I wouldn't spend the extra money on multiple co units when they're all linked.

The code people get together in a room and decide what's safe and what's not safe. I think they're geared towards large developers, done to protect buyers with little original research being done.

Case in point, ionization smoke alarms. If you look at real world test data it becomes obvious that they take far longer to respond to smoldering fires than photo detectors. Yet a ionization alarm only system complies with codes 'cause they pass UL tests.

If codes had any logic to them ionization-only alarms would be prohibited in sleeping areas, interconnect system with one monoxide alarm would be allowed but no.

To answer the original question though, i've never seen a co-ion-photo combo sold. If the bedrooms are getting photo electric smokes, don't hesitate to put a co-ion combo in the call.
 

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I don't understand the need for a CO detector in a bedroom, especially when it's required in the hallway by the stairs just outside the room. Make sure your local inspector can point you to a written reg or bylaw and not just his warped interpretation on what's Code.
 

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Pharon;2779450 "I don't understand the need for a CO detector in a bedroom, especially when it's required in the hallway by the stairs just outside the room. Make sure your local inspector can point you to a written reg or bylaw and not just his warped interpretation on what's Code."


It's supposed to be an early warning system. Some people are really deep sleepers and might sleep through one outside a closed door. This is just a supposition based on years of watching people sleep. They have to take into consideration all kinds of people.

Each one of our US states seem to be different: http://www.ncsl.org/research/enviro...carbon-monoxide-detectors-state-statutes.aspx
 

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It's supposed to be an early warning system. Some people are really deep sleepers and might sleep through one outside a closed door. http://www.ncsl.org/research/enviro...carbon-monoxide-detectors-state-statutes.aspx
yes.
"Door closed" is the key issue. A living space requires its own smoke/co if there is a door separating it from the next nearest detector.

Technically if you were to PERMANENTLY remove your bedroom door (hinges, door jamb and all) you would not need an additional detector in that room.

It's worth mentioning with CO detectors that they are not required in most locals if you do not have any gas or or fossil fuel driven devices (an all electric house). Seems pretty obvious, but some don't know this.
 

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It's worth mentioning with CO detectors that they are not required in most locals if you do not have any gas or or fossil fuel driven devices (an all electric house). Seems pretty obvious, but some don't know this.
Most locales, where ?
In California, a single family residence is required to have a CO detectors, if it has an attached garage. Doesn't matter if it is all electric.

Any multi dwelling unit building (starting with a duplex) is required to have them. The all electric (or no attached garage), does not exempt them from the requirements.
 

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In an interconnected system any monoxide signal needs to be audible, and if you have a smoke alarm in each bedroom in an interconnected system with one monoxide alarm, it will be audible.

The putting monoxide detector in each bedroom is simply nonsense.

Even through a closed door, an alarm in the hall should be audible.

I think codes should provide a basic level of protection with an alarm on each floor. Anything above and beyond that, the owner or tenant should add battery powered units. Alarm in each bedroom may be a good idea for bedroom fires, but it shouldn't be mandated. Housing is already expensive as is.

The focus needs to be on the flawed UL standards and tests instead.

Monoxide alarms don't go off below 70ppm, you could have a chronic level of 50 for months or years and get sick with no peep from one of these alarms.

The ionization smoke alarms are also bad, taking a very high concentration of smoke from cold smoldering fires to alarm. The tests don't reflect reality; there's lots of info online about this issue, the manufacturers know it.
 

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Most locales, where ?
In California, a single family residence is required to have a CO detectors, if it has an attached garage. Doesn't matter if it is all electric.

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That's why I said you have to check your local code. In Ontario for example if you're all electric (no attached garage) you don't have to have a CO

  1. Do all newly constructed residential buildings require the installation of a CO alarm?
Yes. Under the OBC, CO alarms have been mandatory in new residential buildings containing a fuel-burning appliance (e.g. a gas furnace/stove) or a storage garage (for motor vehicles) since 2001. Until these OFC amendments, there were no provincial requirements for CO alarms in properties built before 2001. However, many municipalities have required these devices through municipal by-laws.



  1. Do all existing residential buildings require CO alarms?
Existing residential occupancies that contain at least one fuel-burning appliance (e.g., gas water heater or gas furnace), fireplace or an attached garage, require the installation of a CO alarm.
[Div. B, 2.16.1.1.(1)]
http://www.mcscs.jus.gov.on.ca/engl...s/QuestionsandAnswers/OFM_COAlarms_QandA.html
 

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In an interconnected system any monoxide signal needs to be audible, and if you have a smoke alarm in each bedroom in an interconnected system with one monoxide alarm, it will be audible.

The putting monoxide detector in each bedroom is simply nonsense.

Even through a closed door, an alarm in the hall should be audible.

I think codes should provide a basic level of protection with an alarm on each floor. Anything above and beyond that, the owner or tenant should add battery powered units. Alarm in each bedroom may be a good idea for bedroom fires, but it shouldn't be mandated. Housing is already expensive as is.

The focus needs to be on the flawed UL standards and tests instead.

Monoxide alarms don't go off below 70ppm, you could have a chronic level of 50 for months or years and get sick with no peep from one of these alarms.

The ionization smoke alarms are also bad, taking a very high concentration of smoke from cold smoldering fires to alarm. The tests don't reflect reality; there's lots of info online about this issue, the manufacturers know it.
I don't know if the CO exposure standards are different but the alarms I am familiar with alarm at a much lower level. The TLV for 8 hours is something like 35ppm.

As far as the additional cost for a smoke in each bedroom driving up the cost of a home you must be kidding. An increase of less than $400 or $500 dollars would hardly be noticed, especially when amortized over the life of the mortgage.

I would not say the tests are flawed simply due to the different characteristics of a smoldering and free-burning fire. One sensor is simply not the best solution.
 

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There are countless videos of real world independent test showing the ionization alarms failing to go off in a timely manner in smoldering fire tests involving synthetic materials. like if a cigarette butt is dropped on a couch.

For photo-electric it's different and they provide a decent warning for all fires. ions often don't go off for an hour or more in certain smoldering fires.

this is a complex topic but the tests that ul does apparently don't reflect reality now. materials have changed maybe.

As for monoxide, i would would want an alarm to sound a warning as soon as there's exposure, like 10ppm or something.

here's the standard:

Basically, the problem with UL listed alarms is that they're meant to offer protection to healthy adults during very high levels of CO in a home's air. So how much CO does a UL listed alarm allow you to breathe?

  • 30 ppm for up to 30 days <-This one is scary because a homeowner can reset the alarm and just assume it's a false trip.
  • 70 ppm for up to 4 hours
  • 150 ppm for up to 50 minutes
  • 400 ppm for up to 15 minutes

Read more: http://www.greenbuildingadvisor.com...oxide-alarm-may-not-protect-you#ixzz3uG0ocaCv
Follow us: @gbadvisor on Twitter | GreenBuildingAdvisor on Facebook

Totally unacceptable. A properly operating gas appliance will have 20ppm +/- in the exhaust; you could have a water heater backdraft for months or years without any alarm from one of these UL detectors.

I suspect the building codes are written by the industry, for the industry to raise sales. For UL standards i know fire departments lobbied to prevent monoxide alarms from giving low level warnings.
 
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