Which of the following practices is advised during methane checks?

The recommended practice during methane checks is to avoid synthetic fuels. Synthetic fuels can contribute additional hydrocarbons and impurities into the sampling environment, which may interfere with the accuracy of methane measurements. Accurate monitoring of methane levels is crucial for ensuring safety in mining and other industries where methane is prevalent, as it is a flammable gas and poses significant hazards if not properly managed.

By avoiding synthetic fuels, you minimize the risk of introducing variables that could skew the readings or misrepresent the true methane levels in the area being monitored. Accurate methane checks are critical for implementing effective safety measures and regulations, thus maintaining a safe working environment.

The other practices suggested, such as conducting checks at random times or calibrating only when necessary, do not foster reliable monitoring protocols. Regular and systematic checks are essential for effective methane management.