13. (1) Where the minimum rates of wages have been fixed under this Code, the appropriate Government may -
(a) fix the number of hours of work which shall constitute a normal working day inclusive of one or more specified intervals;
(b) provide for a day of rest in every period of seven days which shall be allowed to all employees or to any specified class of employees and for the payment of remuneration in respect of such days of rest;
(c) provide for payment for work on a day of rest at a rate not less than the overtime rate.
(2) The provisions of sub-section (1) shall, in relation to the following classes of employees apply, only to such extent and subject to such conditions as may be prescribed, namely:-
(a) employees engaged in any emergency which could not have been foreseen or prevented;
(b) employees engaged in work of the nature of preparatory or complementary work which must necessarily be carried on outside the limits laid down for the general working in the employment concerned;
(c) employees whose employment is essentially intermittent;
(d) employees engaged in any work which for technical reasons has to be completed before the duty is over; and
(e) employees engaged in a work which could not be carried on except at times
dependent on the irregular action of natural forces.
(3) For the purposes of clause (c) of sub-section (2), employment of an employee is essentially intermittent when it is declared to be so by the appropriate Government on the ground that the daily hours of duty of the employee, or if there be no daily hours of duty as such for the employee, the hours of duty normally include periods of inaction during which the employee may be on duty but is not called upon to display either physical activity or sustained attention.