What is a Photoelectric Smoke Alarm?
What is a photoelectric smoke alarm?
A photoelectric smoke alarm is an integrated system of photodetector/sensor, light source, power source and alarm. They are generally efficient in detecting both smouldering and fast-growing fires. It utilises the behaviour of light particles in the air media and triggers a fire alarm in the event that smoke is present.
How does a photoelectric fire alarm work?
Photoelectric or optical smoke alarms are generally made up of a light source (modernly using LED), a photodetector, battery and an electronic circuit integrated with an alarm. All these components work together and compose a photo-optical smoke alarm. Once a threshold or a significant difference in the amount of light reaching the sensor (typically because smoke is present), the electronic circuit triggers the alarm.
What is the difference between an ionisation and photoelectric fire alarm?
The main difference between an Ionisation and Photoelectric Fire alarm is the mechanism in which they are triggered. According to studies, Ionisation Fire Alarm is only effective when there’s a rapidly developing fire while a Photoelectric Fire Alarm performs excellently and reliably both in rapid and smouldering fires. Most Australian fire authorities promote photoelectric smoke alarms.
What do you look for when buying a photoelectric fire alarm?
If wireless, look for photoelectric fire alarms with batteries that last long, such as lithium batteries that can last up to 10 years. Look for long-range alarms that can be interconnected with other units in other rooms with visual indicators and louder alarm sound. Finally look for alarms which meet Australian Standard AS 3786-2014 and have a testing function to ensure smoke alarms are always working properly.