The most established application is for lighting when occupancy sensors turn off lights when no one is present. Many building automation systems can maintain a suitable level of comfort and efficiency with less power when they have accurate information on whether people are present in the served area. Applications that are growing include using occupancy data to improve space planning for desk hoteling and to help buildings optimize maintenance schedules. Also, accurate occupancy information is central to the performance of building access and security systems that allow, restrict, and monitor employee access.