Since the holiday season is typically the most hazardous time of the year for house fires I thought a review of smoke alarms might be warranted. A functioning smoke alarm can save the lives of you and your family… on the other hand a smoke alarm that does not function well, or the wrong type of alarm, might not give you the warning you need to get to safety in the case of a house fire.
A lot of people would be surprised to know that there are actually two completely different types of smoke alarms that have different sensitivities to different types of fires. This is important because if you have the wrong type of alarm in the wrong room you might not get the warning you need.
Ionization smoke alarms are the cheapest and most common in U.S. homes. I won’t go into how they work, but they are good at detecting what fire experts call ‘flaming’ fires.
Photoelectric smoke alarms are a little more expensive, use a different principle to detect fire and) are good at detecting ‘smoldering’ fires.
So how do you know which ones you should be using?
Nobody can predict the exact fire that might befall your house, but a good rule of thumb is that rooms with easily combustible materials (e.g. basement, near the kitchen) should be fitted with ionization smoke alarms because these rooms tend to burn quickly and cleanly, producing large smoke particles. Rooms that have a lot of furniture in them (living room, dining room, bedrooms) typically produce smoky, smoldering fires and these rooms should be fitted with photoelectric smoke alarms.
If you want to be extra-cautious you can purchase combination smoke alarms – basically a dual unit with the two different technologies packaged together. These are actually required in some jurisdictions.
Of course all of this is academic if you don’t maintain your smoke alarms properly. The U.S. Fire Administration recommends testing smoke alarm batteries once a month and replacing them once a year. In our home we use daylight savings time as the reminder so we always remember when we changed them last. They also recommend replacing smoke alarms after 8 – 10 years.