The Smoke Detector

A smoke detector is a small device attached to the ceiling. It can sense smoke in the air. When it detects smoke, it makes a very loud beeping sound to warn everyone that there might be a fire.

How Smoke Detectors Were Invented

The first smoke detectors were invented in the 1890s, but they were too expensive for homes. In the 1960s and 1970s, companies started making affordable home smoke detectors.

Governments began requiring smoke detectors in homes and buildings. Today, almost every home has at least one smoke detector. They have saved thousands of lives by giving people early warnings about fires.

How Smoke Detectors Work

There are two main types of smoke detectors. One type uses a tiny beam of light. When smoke enters the detector, it scatters the light and sets off the alarm.

The other type uses a small amount of safe radiation. Smoke particles block the radiation and trigger the alarm. Both types are very good at detecting fires early. You should test your smoke detectors every month by pressing the test button.

Fun Facts

• Smoke detectors cut the risk of dying in a home fire by about 50 percent.
• You should change the batteries in smoke detectors at least once a year.
• The loud beep of a smoke detector can reach about 85 decibels.

Did You Know?

Some smoke detectors are now smart and can send an alert to your phone if they detect smoke while you are away from home.