4CM Carbon Monoxide Sensor
City Technology's 4CM, carbon monoxide sensor was developed to meet the most stringent toxic gas and mining standards. The 4CM improves the functionality, reliability and effectiveness of PPE in hostile environments, by responding 12 percent faster to CO hazards and recovering in over half the time of the industry average. It has a typical T90 time of seven seconds and a recovery time to an indicated level of less than 2ppm in less than 100 seconds. During 50-day exposures in 120°F and 11 percent relative humidity, and 120°F at 95 percent relative humidity, the 4CM operated to specification. The sensor provides excellent accuracy and stability at high and low gas concentrations, meeting the EN45544 requirements for uncertainty, typically achieving 1ppm for zero concentrations and less than 1 percent variation at 250, 750 and 1000ppm.