(1)It shall not be lawful for a number of persons greater than the permitted number to be employed at any time at a mine of coal, stratified ironstone, shale or fireclay in a shaft or outlet:
Provided that, in relation to an outlet toot being an unwalkable outlet), this subsection shall not apply to any part thereof lying between the surface entrance thereto and any point therein from which a communication leads to another outlet or to a shaft, being an outlet or shaft available to persons employed in the said part for affording to them means of ingress and egress.
(2)For the purposes of this section—
(a)the permitted number, in relation to a shaft or outlet, shall be twenty or such greater number (not exceeding thirty) as may be determined by an inspector by notice served on the manager of the mine ;
(b)the insets of a shaft or outlet shall be deemed to form part of the shaft or outlet; and
(c)subsection (6) of section twenty-two of this Act shall apply as it applies for the purposes of that section.
(3)Nothing in this section shall be construed as prejudicing the operation of the last foregoing section in relation to the employment of persons in individual insets of a shaft or outlet.