157. Main mechanical ventilator, its drive and fittings etc.
(1)Every main mechanical ventilator in a mine shall be capable of producing adequate ventilation in the mine or part and shall be installed on the surface at a distance of not less than 10 metres from the opening of the shaft or incline at any point.(2)If electricity is used for driving the mechanical ventilator, electrical energy shall be supplied to the drive motor of the ventilator through a separate circuit from the main distribution point of the mine.(3)In every gassy seam of second or third degree, two different sources of power to the mechanical ventilator shall be provided.(4)There shall be provided and maintained at every main mechanical ventilator, a recording instrument to continuously register the pressure developed.(5)Every main mechanical ventilator shall be so designed, installed and maintained that the current of air can be reversed when necessary.(6)At every shaft or incline ordinarily used for lowering or raising of persons or materials where a mechanical ventilator is installed, there shall be provided a properly constructed air lock.
