Ionization or Photolelectric?

After reading the following story in today’s Citizens’ Voice--Fire chief: Home did not have smoke alarms--it occurred to me that we read about these sorts of warnings each and every year.
　
An excerpt: The Kingston home where three people died Monday in a fast-moving fire did not have smoke detectors, Kingston fire Chief Frank Guido said Wednesday.

With the tragedy still fresh in the public's mind, Guido reminded residents they need smoke detectors - and they can get them for free.

The Kingston Fire Department has a collection of 100 smoke detectors available for free to residents of Kingston and Forty Fort, while other departments conduct similar handouts, the chief said.

After not much thought, I realized that the two smoke detectors we have in this house were installed by members of the Wilkes-Barre Fire Department in 2001, maybe 2002. Being that technology advances so rapidly, making it difficult to keep abreast of, I figured some research was called for.

This October 29, 2008 story--Don’t Change Your Batteries - Change Your Smoke Detector, Too--confirmed my suspicions, that perhaps my smoke detectors are woefully dated and inadequate.

It is estimated that up to 80-90% of the smoke detectors installed in private residences are of the ionization variety. Not only has the International Association of Firefighters (I.A.F.F.) officially called for the ionization units to be replaced by the newer photoelectric units, Boston Fire Chief Jay Fleming has been calling for the effective ban of ionization units since the 1990's.

Have you ever disabled your smoke alarm because you were cooking, smoking, showering or burning a scented candle? If so, you disabled an ionization detector because of “nuisance tripping.”

But, and this is a big but, ionization units react quicker to open-flame fires, while photoelectric versions react quicker to slow smoldering fires that have yet to flash-over into a fire. For more on that, peruse this next paragraph…

“On average, ionization units respond about 30 seconds faster to an open-flame fire than photoelectric type alarms. However, in a smoldering fire, ionization units respond on average 30 to 60 minutes slower than a photoelectric unit. In some cases, they may not respond at all. Most residential fire fatalities occur at night and are result of smoke inhalation. The flash-over point in a fire is basically the point where the fire goes critical. Twenty to thirty years ago, the flash-over point in a fire occurred in as little as 12-14 minutes. Due primarily to the increased use of synthetic and engineered materials, flash-over now often occurs in as little as 2-4 minutes. This leaves the occupants significantly less time to safely exit their home in a fire.”--California Real Estate Inspection Association
　
That got to me thinking that perhaps the best set-up is to have one of each; an ionization alarm as well as a photoelectric version. And it should be noted that you can also install units that combine both technologies.

So, rather than Google the thing to death, I figured I’d seek out the advice of a professional firefighter. As a result, Wilkes-Barre Fire Chief Jay Delaney agreed to field and respond to my questions earlier today.

He said that while it’s good to understand the differing technologies, it’s crucial that people have “working” smoke detectors in their homes. And he couldn’t reiterate that “working” part enough. He said we should all have smoke detectors, they should be dusted and have the batteries checked regularly, if not monthly.

He went on to say that having smoke detectors that are not regularly maintained may be doing little more than providing you with “a false sense of security.” He also mentioned it is estimated that only 40% of the smoke detectors installed in homes actually work.

According to him, the City of Wilkes-Barre has provided residents with 400 or so detectors (I forget the timeframe) absolutely free. And many of them were installed by the city’s own firefighters. If you need new units, supplies are dwindling. His overriding point was, with the City offering free smoke detectors on a first-come, first-serve basis, there’s really no excuse for not having at least one. They currently have Kidde ionization detectors on hand that include batteries.

Since both the ionization and photoelectric units seem to have their strengths and weaknesses depending on the density of the smoke, I asked if I should install one of each. “Absolutely,” was the quick response.

I do thank him for his time, but I feel I’d be doing him as well as you a disservice if I didn’t take his lead and reiterate all over again, it’s crucial that people have “working” smoke detectors in their homes.

You’ve all gotten your new 2011 City calendars, so why not pencil in some regular maintenance. Smoke detectors provide quicker detection, faster responses from emergency responders, less loss of property and they flat-out save lives.

Get to it.

Later