More than 2600 Americans die from home fires each year. Smoke inhalation is a major cause of death. Just two or three breaths of toxic smoke can knock you unconscious. After that, death is just a step away.
Alarms are inexpensive and easy to install. When smoke is detected, the alarm sets off an ear-piercing sound that can wake you from a sound sleep.
There are two kinds of smoke alarms: ionization Elf Bar Disposable Vapes and photoelectric. The U.S. Fire Administration recommends you install both because they detect distinctly different kinds of fires.
These alarms are better at detecting small amounts of smoke produced by flaming fires, such as a kitchen fire.
If you pulled one apart, you would find a small ionization chamber and a tiny amount of a radioactive material known as americium-241. The ionization chamber is really two small metal plates. One of the plates has a positive voltage. The other is negative. Alpha particles from the americium-241 ionize the oxygen and nitrogen atoms in the air that is present in the chamber.
When an atom is ionized, an electron escapes. This leaves you with a free electron (with a negative charge) and the remaining atom, which now has a positive charge. The free electrons are attracted to the positive plate, while the remaining atoms head toward the negative plate. These movements produce a small electrical current that the smoke alarm can measure. As long as the current stays within an expected range, the smoke alarm stays quiet.
When smoke enters the chamber, the smoke particles attach themselves to the ions and disrupt the current. The smoke alarm senses a drop in the electrical current and automatically sets off a loud horn designed to alert you to the smoke.
In case you’re worried about radiation, the amount used in the smoke alarm is tiny. It won’t hurt you. Simply follow the manufacturer’s directions for use. When you replace your smoke alarm, make sure to dispose of it properly.
Smoky fires can occur when, for example, a couch is smoldering inside but has not yet caught flame. Fire alarms that use photoelectric detectors are better at detecting these kinds of fires.
Inside this kind of smoke alarm are a light and a sensor that are positioned at 90-degree angles to one another. Under normal circumstances, the light shoots straight ahead and is completely undetected by the sensor. When smoke gets into the chamber, light gets scattered. Some of it hits the sensor, which triggers a loud alarm.
Dual Sensor Smoke Alarms
These are smoke alarms that contain both ionization and photoelectric detectors. These alarms are more expensive than those with a single detector, but they can be very cost effective depending on your needs and preferences.
Placing Smoke Alarms
The U.S. Fire Administration (USFA), National Fire Protection Association (NFPA) and others all recommend that you install at least one smoke alarm on every floor in your house, including the basement. More alarms will give you better coverage.
For greatest safety, install a smoke alarm in each bedroom. Put another alarm in the hallway just outside the bedroom and in each of the other rooms in your house.
Where possible, position your smoke alarm in the middle of the ceiling. Keep it away from heating and cooling ducts that could trigger false alarms.
Battery-operated alarms generally have manufacturer’s instructions that are easy to follow. In most cases the only equipment needed is a screwdriver.