Type II (WPII) shall have, in addition to the enclosure defined for a Type 1 weather-protected machine, its ventilating passages at both intake and discharge so arranged that high velocity air and airborne particles blown into the machine by storms or high winds can be discharged without entering the internal ventilating passages leading directly to the electric parts of the machine itself. The normal path of the ventilating air which enters the electric parts of the machines shall be so arranged by baffling or separate housing as to provide at least three abrupt changes in direction, none of which shall be less than 90f . In addition, an area of low velocity not exceeding 600 feet per minute shall be provided in the intake air path to minimise the possibility of moisture or dirt being carried into the electric parts of the machine.