To ensure worker safety it’s important for users of combustible, or LEL (Lower Explosive Limit), gas detectors to consider three factors: 1) the need for frequent verification procedures; 2) scale of calibration for proper sensitivity; and 3) type of gas mixture used for calibration to protect against selective loss of sensitivity due to sensor poisoning.
The safest course of action is to do a functional “bump†test prior to each day’s use. It is not necessary to make calibration adjustments unless readings are off by more than ten percent of the expected value.