Dip tubes are used for liquid level measurements in the compartments of road tankers transporting fuel. They are fitted with flame arresters intended to eliminate the hazard of explosion originating outside the tanker from propagating within the tanker compartments. These arresters cover the necessary openings in the wall of the dip tubes and are designed to confine an accidental explosion within the tube. The performance of three dip tubes has been tested. One tube gave a satisfactory performance, the other two failed to stop the transmission of the explosion.