An occupancy sensor detects the occupancy state of a monitored area. The occupancy sensor may be mounted in a standard junction box at various angles and one or more of the ultrasonic sensors may be disabled. The occupancy sensor includes a PIR sensor and one or more ultrasonic sensors. The sensor sensitivities and timeout settings may be programmed by a technician or user via an IR interface or via a network interface. The settings may be changed according to control system logic or some other factor such as date, time or room conditions. Setup of the sensor may also be performed via the IR interface or network interface. The occupancy outputs both a signal taking into account the timeout period as well as a raw data signal. The IR interface may be used to relay messages between a control system and external devices. Algorithms employed in the occupancy sensor allow for the occupancy sensor to process analog signals from sensors to determine the room state, enhance performance such as by reducing false trips, enhance energy savings and force sensors into vacancy or occupancy mode. The occupancy sensor additionally comprises a microphone. Sound can be required to qualify detection from another sensor and may be employed to prolong the occupancy state once it is established.