Sniffing out false alarms

A new sensor that can distinguish between smoke from a fire and cigarette smoke has been developed by a consortium of European scientists. "Currently, 90% of regular fire alarms are false," explains project coordinator Florence Daniault, "Nevertheless, the emergency services must investigate every alarm logged, which is enormously inefficient." The new detector is based on sensitive conducting polymers, the electrical resistance of which changes depending on the presence of different surrounding gases. An array of polymers was incorporated into the device, which produces a characteristic response depending on which gases are present - whether from a "real" fire or cigarette smoke.