Occupancy sensors save energy by automatically turning lights off when areas are vacant. Occupancy sensors add convenience by turning lights on when the device senses human presence through motion or by body heat. These
devices can range from a simple passive infrared detector built into a light switch to a networked detector that controls lights and also contributes to an integrated facility automation strategy. Sharing occupancy/vacancy information with other components of a facility automation system can also save additional energy. These sensors can be wall mounted to replace an existing light switch, or ceiling mounted or fixture mounted for ease of operation. It is very important to understand the lighting system zoning so that it is easy to determine the area impacted when the lights are turned off. It is also important to review where and how many emergency lights are available in the space being controlled by the occupancy sensor to ensure enough light is available in case of an emergency.