Fuente: Wipo "Sensorization" A sensor device (10) comprises an environmental sensor (22) for determining an environmental parameter associated with a sensor gas flow (F2) through the sensor device. The environmental sensor may be a particulate matter sensor for detecting particulate matter in the sensor gas flow. The sensor gas flow is preheated upstream of the environmental sensor (22). To this end, waste heat generated by the environmental sensor (22) itself and/or by a different sensor (12) that is comprised in the sensor device is used. In this manner, the effects of evaporable droplets in the sensor gas flow (F2), as typically present in fog, may be reduced. In some embodiments, a fog signal is derived.