SYSTEM FOR DETECTING AN ITEM WITHIN A SPECIFIED ZONE

The disclosure reveals a system for detecting one or more persons in a specified zone. A determination is whether there is a person in the zone. A presence determination module may indicate from a current image of the zone compared with a reference image of the zone, whether there is a person in or not in the zone. An illumination controller may assure that the zone is sufficiently illuminated for a current image sufficient for comparison with the reference image to determine a possible presence of a person in the zone. The illumination may be infrared. The system may be used to assure appropriate and adequate face velocity at a fume hood having the presence of a person and having minimal face velocity in the absence of a person at the fume hood.