What Is the Science Behind Smoke Detectors?

Smoke detectors near Annapolis are very useful devices in homes and businesses. Not only do they alert you when smoke levels are high, but some advanced models on the market today can also detect carbon monoxide, offering another means to protect your and your family. If you’re thinking about installing smoke detectors, or you’re considering upgrading your home or business’s current units, enlist the help of a professional who offers residential and commercial electrical services. Even though smoke detectors are common, most people don’t know how they actually work. Here’s the science behind these incredibly helpful devices.

Smoke Detectors Protect People

Smoke detectors are manufactured to be extremely sensitive and annoyingly loud – it seems that a minute amount of smoke can set them off. Though they may go off in the most inopportune times, smoke and carbon monoxide detectors are sophisticated and necessary tools to alert people of danger. After all, you really wouldn’t want to live in a home without a smoke detector, would you?

How Ionization Smoke Detectors Work

There are two main types of smoke detectors available to you: ionization detectors and photoelectric detectors. An ionization detector contains an ionization chamber that, in turn, contains ionizing radiation. Two facing plates – one positive and one negative­ – within the chamber are activated by a charge from the device’s battery. Ionized radiation is created when air containing oxygen and nitrogen atoms passes through the charged chamber. When smoke enters the chamber, it interrupts the steady ionization process and interferes with the electrical current between the charged plates. This interruption triggers the smoke detector to sound an alarm.

How Photoelectric Smoke Detectors Work

Photoelectric smoke detectors use light-emitting diodes that send beams of light across the ceiling of chambers shaped like the letter T. At the base of one of these T-shaped chambers is a photocell that detects light. When smoke makes it into the chamber and interferes with the light projected within, the light becomes scattered as it hits the base of the T-shaped chamber, and as it comes into contact with the photocell. If the photocell detects scattered light, it sets off a trigger that sends the signal to sound an alarm. Photoelectric smoke detectors are made to detect smoke from smoldering fires that are less intense than roaring fires. Therefore, they’re not as sensitive as their ionization counterparts.