MASTECH MS6310 Combustible Gas Detector 10%-40% for Methane Solid State easy to use Operating environment and condition: 600V CAT.V, pollution grade: U. Elevation &lt; 2000 m Environment temperature and humidity: 0~40C, &lt;80% RH (do not use meter when temperature &lt;10C). Temperature coefficient: 0.1L Accuracy/C(28C).