Section 30. Hours of work above ground

30. Hours of work above ground.— (1) No adult e^ninved u'.-jve ground in a mine shall be requirtd or allowed to work for more than forty-eight hours in any week or fur more th.i-i nine hours in any day. (9) The periods of work of any such adult shall be so arranged that, along with his interval for refit, they shall not in any day spread over more than twelve hours, and that he shall not work for more than five hours continuously before he has had aa interval for rest of at lenst half an hour: Provided that the Chief Inspector may, for reasons to be recorded, increase the ptr'od of spread ovr io fourteen hours in any day. (3) No person belonging to two or more relays shall be flowed to do work of the same kind above ground at the same moment: Provided that, for the purposes of this sub-section, persons shall not be deemed to belong to separate relays by reason only of the fact that they leeeive their intervals for rest at different times.