law: Factories Act, 1948 
  65. Power to make exempting orders 
  (1) Where the State Government is satisfied that, owing to the
  
  nature of the work carried on or to other circumstances, it is unreasonable to
  
  require that the periods of work of any adult worker in any factory or class or
  
  description of factories should be fixed beforehand, it may, by written order,
  
  relax or modify the provisions of section 61 in respect of such workers
  
  therein, to such extent and in such manner as it may think fit, and subject to
  
  such conditions as it may deem expedient to ensure control over periods of work.
  
  
  (2) The State Government or, subject to the control of the State
  
  Government, the Chief Inspector may, by written order exempt, on such
  
  conditions as it or he may deem expedient, any or all of the adult workers in
  
  any factory or group or a class or description of factories from any or all of
  
  the provisions of section 51, 52, 54 and 56 on the ground that the exemption is
  
  required to enable the factory or factories to deal with an exceptional press
  
  of work.
   84  [(3) Any exemption granted under sub-section (2) shall be
  
  subject to the following conditions, namely- 
  ( i ) the total number
  
  of hours of work in any day shall not exceed twelve;
  (ii) the spread over, inclusive of intervals
  
  for rest, shall not exceed thirteen hours in any one day;
  (iii) the total number of hours of work in any
  
  week, including overtime, shall not exceed sixty;
  (iv) no worker shall be allowed to work
  
  overtime, for more than seven days at a stretch and the total number of hours
  
  of overtime work in any quarter shall not exceed seventy-five.
   Explanation :  In this sub-section "quarter" has
  
  the same meaning as in sub-section (4) of section 64.]