Did You Know? Carbon Monoxide Sensors Do Not Detect Diesel Exhaust?

Popular uses of carbon monoxide sensors in the building automation industry involve monitoring vehicle exhaust. Sensors are commonly installed in parking garages to monitor carbon monoxide levels and provide an input signal for a ventilation control system or building automation system. This system then controls the ventilation by opening dampers and controlling fans to maintain acceptable carbon monoxide levels. Sensors are also utilized to prevent introducing carbon monoxide into the building when the outside air intake is located in an area where exhaust fumes may be present, such as near loading docks. In this application, the presence of carbon monoxide will cause the outside air dampers to close and remain closed until the outside air is free of fumes. Kele now offers two products that may be used in these applications. The WCO-1B Carbon Monoxide Sensor provides a 4-20 mA output over 0-200 ppm. The new GMT-CO Series Gas Monitor/Transmitter is also available for sensing carbon monoxide and includes a 4-20 mA output over 0-250 ppm, and an alarm relay factory set at 35 ppm. Table 1 shows exposure levels recommended by several agencies.