... -computer analysis, directly measure the thickness of HC, CO and CO2 in the exhaust gas of vehicles and inspect ... ±1Hz2.Measuremnt scope:HC:0-1000010-6(ppm)vol CO: 0-10.0 10-2(%)vol CO2: 0 ... measuring petrol rotate speed.4.preheat time:10mins5.resolution:CO: 0.01%vol HC:1ppmvolnormal hexane equivalent CO2: 0 ... rate speed: 1rpm oil temperature:0.1°C6.indicated error:CO:±0.06% vol or±5% relative error. HC: ...