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smoke alarm

cda

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Interesting!

  • An ionization smoke alarm is generally more responsive to flaming fires, and a photoelectric smoke alarm is generally more responsive to smoldering fires. For the best protection, both types of alarms or a combination alarm (photoelectric and ionization) should be installed in homes.
NFPA Smoke alarm safety tips



Virginia state motto: "Sic Semper Tyrannis"



Francis
 
Photoelectric are the only approved detectors in Vermont.

So Francis, who is the lady that the state was named after?
 
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ICE said:
Photoelectric are the only approved detectors.
Well that is all that is used around here for years in residential setting. Where does it state that an ionized unit cannot be used.
 
Dennis said:
Well that is all that is used around here for years in residential setting. Where does it state that an ionized unit cannot be used.
This is from the link that CDA provided.

NFPA 101[9.6.2.12] Photoelectric Smoke Alarms: All newly installed smoke alarms in dwelling units, lodging or rooming houses, hotels and dormitories, shall be the photoelectric-only-type.
I didn't say that they can't be used....just that they aren't approved as the only detector....as long as there is a photoelectric type detector there can be as many ionization type detectors as anyone wants.
 
ICE said:
This is from the link that CDA provided.I didn't say that they can't be used....just that they aren't approved as the only detector....as long as there is a photoelectric type detector there can be as many ionization type detectors as anyone wants.
Gotcha but that is only for the state of Vermont not a national code.
 
Dennis said:
Gotcha but that is only for the state of Vermont not a national code.
Yes that is correct.

I wondered why Vermont has banned combination smoke alarms.

So I Googled it and came up with this:

Currently, ionization-type smoke detectors are banned in three states: Massachusetts, Iowa, and Vermont. However, elsewhere they are the dominant type of smoke detector, due to their low price.Now, what many people are unaware of is that there is a very serious problem with ionization-type smoke detectors: they are very poor at detecting slow smoldering fires. Ionization-type smoke detectors can take 15 to 30 minutes longer to sound than a photoelectric-type smoke detector, and sometimes won't even sound at all. Slow smoldering fires account for more deaths than fast flaming fires anually, most of which occur during the overnight hours.

Here is an in-depth explaination of the problems of ionization-type smoke detectors:

Smoke Alarm Lawsuits | Defective Smoke Alarm Lawyers Mobile AL (http://www.taylormartino.com/product_liability/smoke_alarms/smoke-alarm-lawsuit.cfm - broken link)

Luckily we installed photoelectric-type detectors in our house in Rio Rancho, and when we move to the Phoenix area, if the new house only has ionization-type smoke detectors, we will replace one of them on each floor with photoelectric-type detectors.

While manufacturers claim that ionization-type smoke detectors are faster at detecting fast flaming fires than photoelectric, studies have shown that the difference in response time is insignificant. However, with slow smoldering fires, the photoelectric-type smoke detectors are much faster at detecting them than ionization-type detectors.

Of course, there also exists dual sensor smoke detectors, which contain both a photoelectric and an ionization sensor, however, I don't think they are worth the price since they would only offer slightly better protection for fast flaming fires than photoelectric-only alarms, and would not make any difference for slow smoldering fires.

So, does anyone here think there should be a ban on ionization-type smoke detectors, considering the loss of lives they have caused due to poor detection of slow smoldering fires?
Most of the homes that I inspect have a combination smoke/intruder alarm. Chihuahua is the most popular. They must only come in pairs because there is never just one. I set them off every time.
 
Last edited by a moderator:
ICE said:
Most of the homes that I inspect have a combination smoke/intruder alarm. Chihuahua is the most popular. They must only come in pairs because there is never just one. I set them off every time.
LOL, very clever indeed. :D
 
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