For energy savings, DCV systems are more and more used in ventilation systems. In France, in nonresidential buildings, these systems are generally controlled by either a CO2 sensor, or an opticalmovement detection (infrared). The part of the study we present here was to determine laboratorytests methods to assess the performances of optical sensors for ventilation application. The pointwas to characterise them by checking their detection in front of some determined movements orevents.