This study evaluates the accuracy of volatile organic compounds (VOC) and particle matter(PM) sensors marketed for ventilation purposes. VOC sensors were tested using knownconcentrations of VOC-gases, according to ISO 16 000-29. Further, PM sensors together witha reference instrument were exposed to aerosols originating from cigarette smoke, salt and oil.Results show that all tested VOC sensors do not respond to all test gases. Also, two copies ofthe same VOC sensor do not give the same output. PM sensors generally measure lowerconcentrations compared to the reference instrument and show higher accuracy for PM10 thanfor PM1 and PM2.5. Although the results seem discouraging, several of the sensors respondto changes in concentrations and thus might have the potential to be used for ventilationcontrol. Further, the results imply that using the sensors for purpose of determining ormeasuring the indoor air quality (IAQ) is not possible.