Paging Dr. Frischer: Smoke Detectors

Catastrophic fires have been in the news, and my heart goes out to those who have suffered loss.

Smoke alarms can be a nuisance. Smoke alarms located near our kitchens may detect food cooking, even if it’s not actually burning. My own children would loudly proclaim, whenever our ancient toaster (frequently) triggered the smoke detector, that “The bagels are ready!”

But consider that, according to a 2021 report by the National Fire Protection Association (NFPA), an up-to-date, well-functioning smoke alarm reduces the risk of death in a fire by a whopping 55%.

Photoelectric detectors work by detecting light reflected off particles inside a chamber. When particles are present and the amount of light registered by the light detector reaches a certain level, the alarm sounds.

Ionization detectors use a very small amount of safely shielded radioactive material that electrically charges (ionizes) air molecules between two metal plates. A small electric current flows from one plate to the other. Particles enter a chamber, attract the ions, and carry them away, reducing the current. When the current falls below a certain level, the device registers those particles as smoke, and the alarm sounds.

Both types of detectors can detect either slow-burning “smoldering” fires or fast-burning “flaming” fires, but each technology has its own strengths and weaknesses. Most smoke alarms purchased are photoelectric. In theory, having both types of detectors (dual-sensor) in the home is best.

New tests and standards are being developed to make smoke alarms better at detecting the kinds of smoke we want them to detect, and not the kinds we don’t. The goal is to avoid any temptation to disable the alarms and to put ourselves in danger. The next generation of smoke detectors is expected to cut down on the number of nuisance alarms, and signal real fires more quickly. Time is everything when it comes to saving lives and property.

I urge you to check that you have working smoke alarms in your home, that there are enough of them, and that they are in the proper locations. Investigate what type they are, and consider buying newer dual-sensor technology. Consider hybrid smoke and carbon monoxide detectors.

Always remember Benjamin Franklin’s words: “An ounce of prevention is worth a pound of cure.”