Option measurement of carbon monoxide & hydrogen sulphide Measuring / indication ranges: CO 0 - 300 / 0 - approx. 1,000 ppm H2S 0 - 100 / 0 - approx. 200 ppm Resolution: CO 1 ppm H2S 0.1 ppm This option can only be ordered in combination with the sensor array option (282102) or the Dual IR sensor option (282103).