If You Have These Smoke Alarms, Get Rid Of Them!
There are two types of smoke alarms, photoelectric and ionization. Which one should you use? Ionization alarms respond marginally faster to an open or “fast-flame” fire than a photoelectric smoke alarm. On average, ionization alarms will react about 30 to 90 seconds faster to this type of fire.
However, nearly 100% of residential fire fatalities are from smoke inhalation and not from the actual fire. Most fatal fires happen at night while the occupants are asleep. An ionization alarm will respond 30 to 90 minutes slower to a smoldering fire than a photoelectric alarm. In these situations, a photoelectric alarm will alert the occupants and allow a safe exit about 96% of the time. Ionization alarms will give sufficient warning less than 40% of the time, meaning that 60% of the time someone may die!
A slow response time isn't the only problem with an ionization alarm. Nuisance tripping can occur when cooking, showering, etc. Many times, people become frustrated and intentionally disable the detectors, leaving their household completely unprotected. Approximately two-thirds of all residential fire deaths occur in homes that are unprotected. Ionization alarms account for over 85% of disabled alarms. Most of the remaining fire deaths occur when a smoke alarm sounds too late for the occupants to escape.
Significant research going back to the mid-1970's clearly shows ionization alarms are slow to react to smoldering fires. It has taken decades, but there is finally a growing public awareness of this problem. The International Association of Firefighters (IAFF) recently took a stand, and now recommends that only photoelectric smoke alarms be installed.
Which Ones Do You Have?
If your alarm has a “Hush” feature, it is probably an ionization unit. If the label mentions radioactive material, Americium-241, or if there is an "I" in the model number- it is probably an ionization alarm. If there is any doubt, play it safe and replace the units with photoelectric alarms.
What About Combination Smoke/CO Alarms?
Combination photoelectric/carbon monoxide (CO) alarms are available. Smoke alarms should be replaced every 10 years. CO detectors should be replaced every 5 to 7 years. With a combination unit, you are either replacing the smoke alarm too soon, or relying on a CO detector that is past its expiration date. Separate units make more sense. Photoelectric alarms provide the best protection in real-world fires. This year, don't just replace your smoke alarm batteries – replace your alarms with photoelectric units and recommend that your families, friends, and neighbors all do the same!
Steve Stenros- First Choice Inspections, a CREIA MCI and ICC certified inspector provides home inspections in San Diego, Orange, and Riverside counties in southern California. Clients receive a FREE lifetime appliance RecallChek with every standard inspection. Steve can be reached for appointment at 888-335-3040. If You Have These Smoke Alarms, Get Rid Of Them!
Steve Stenros, MCI
Master CREIA Inspector #0115
ICC Residential Combination Inspector #5251439
Certified Infrared Thermographer #7791
FHA/HUD Inspector- #V975
203k Consultant #S0611
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