Combined carbon monoxide (CO) & visibility tunnel sensor
TunnelCraft 3 Codel International

The TunnelCraft 3 CO/VIS Air Quality Monitor (AQM) uses infrared light and visible light to measure carbon monoxide and visibility in a single compact instrument.
The AQM consists of a transceiver that projects infrared beams to a reflector unit mounted 3m away. The reflected light is received by the transceiver and the specific absorption is measured to determine the visibility dimming coefficient and carbon monoxide concentration in the tunnel atmosphere.

› Measurement of CO by infrared absorption
› Routine maintenance limited to annual cleaning of optical surfaces
› High resolution measurement of visibility
› Current and relay outputs direct from sensor
› Accuracy +/-1ppm for CO, 0.0002m-1 for visibility
› RS232 or RS485 - Modbus output optional
› Designed to withstand the harshest environments
› Also available as a combined CO/NO/Vis sensor