22B.(1) A person employed above ground in a mine shall not be allowed to work for more than fifty-four hours in any week or for more than ten hours in any day. (2) The periods of work of any such person shall be so arranged that, along with his intervals for rest they shall not in any day spread over more than twelve hours, and that he shall not work for more than six hours before he has had an interval for rest of at least one hour. (3) Persons belonging to two or more relays shall not be allowed 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 receive their intervals for rest at different times.