(p)Where the only means of egress in a mine is by apparatus worked by steam or electricity, precautions shall be taken to ensure that the two winding engines do not fail simultaneously, and in particular, in the case of electric winding engines, the engines shall be capable of being connected to two separate power supplies and unless otherwise directed by the Chief Inspector by an order in writing, the provisions of this clause shall be deemed to have been complied if an emergency winding gear is maintained.
