Where a worker in a factory works on a shift which extends beyond midnight,--
         (a) for the purposes of sections 52 and 53, a holiday for a whole day shall mean in his case a period of twenty-four consecutive hours beginning when his shift ends;
         (b) the following day for him shall be deemed to be the period of twenty-four hours beginning when such shift ends, and the hours he has worked after midnight shall be counted in the previous day.