Semiconductor Technology

Semiconductor sensors utilize a controlled quantity of tin dioxide as a sensing element. The sensing material is heated by a small electric heating element and carbon monoxide gas is catalytically broken down at the surface of the sensing element. Electrons are released in this process and are absorbed by the sensing element. This increase in charged particles lowers the resistance of the sensor. In an alarm using semiconductor sensors, electronics are used to measure the sensor resistance and from this to calculate the carbon monoxide concentration.

Semiconductor sensors are mechanically simply and are electronic in nature therefore they hgave a long life and are very reliable. Current designs demonstrate excellent immunity to other gases that may be present.

Millions of semiconductor carbon monoxide alarms manufactured over the past ten years have provided historical data. this demontrates a dependable sensor life of more than 10 years.

Because of this positive history, the results of hundreds of tests by ULC, ULI and BSI over many years, and proven consistency in manufacture, this is the principle technology used by NADI (American Sensors(TM)). The three leading manufacturers in the world use this technology in their popular models.