(9)Where in any mine belowground, a system of haulage roadway (and conveyors, if any) extends to a distance of more than 300 metres from the shaft or the entrance to the mine, efficient telephonic communication shall be provided and maintained between the end of every such system and the bottom and top of the shaft or the entrance to the mine as the case may be: -Provided that where travelling is unguly arduous, the telephonic communication between the end of every such system and the bottom and top of the shaft or the entrance to the mine or in any other, case as may be specified by the Regional Inspector shall be provided and maintained.
