“An optical smoke alarm, also known as a photoelectric smoke alarm, is a type of fire detection device used to detect smoke and potential fires in residential and commercial buildings. It operates based on the principle of light scattering. The alarm contains a light source (usually an LED) and a light-sensitive sensor (usually a photodiode or phototransistor). When smoke particles enter the detection chamber, they scatter the light emitted by the LED, causing some of the light to be directed towards the light sensor.

The sensor detects the scattered light and triggers the alarm when it detects a significant increase in light levels caused by the presence of smoke. This type of smoke alarm is particularly effective at detecting smouldering fires, which can produce large smoke particles that scatter light more efficiently than flaming fires. They are less sensitive to cooking fumes or steam, reducing the number of false alarms compared to other types of smoke alarms.

Optical smoke alarms are widely used in conjunction with ionization smoke alarms (which work on a different principle) to provide comprehensive fire detection coverage in buildings. When a fire starts, the smoke generated can contain a combination of large and small particles, and having both types of alarms can increase the chances of early detection.

It’s important to note that smoke alarms are crucial safety devices and should be regularly tested and maintained to ensure they function properly in the event of a fire emergency. The specific requirements and regulations for smoke alarms may vary by region or country, so it’s essential to follow local guidelines for installation and maintenance.”