Types Of Technologies
There are a number of different occupancy sensor technologies from which to choose.
The right type of technology, given a building's size and usage, will differ from facility to facility.
The following are a selection of technologies as outlined in the U.S. Environmental Protection Agency's (EPA) Focus on Energy report:
Passive infrared (PIR) occupancy sensors: Infrared sensors detect the difference in heat emitted by humans in motion from heat emitted by the background space
Ultrasonic occupancy sensors: Ultrasonic sensors emit a high-frequency signal that is undetectable by humans and animals, which bounces off objects, surfaces and people in a space; it then returns to the sensor, which interprets change in the frequency as motion
Dual-technology sensors: Dual-technology sensors employ both PIR and ultrasonic technologies for maximum coverage and reliability with fewer false triggers because these sensors activate lights only when both technologies detect movement.