To every establishment which is a factory engaged in any industry specified in schedule and in which twenty or more person are employed.
To any establishment employing twenty or more persons or class of such establishment which the central Govt. may by notification in the official gazette specify in this behalf.
To any other establishment employing less than twenty persons, can also be covered u/s 1(4) of the act by notification provided that the employer and the majority of the employees are agreed that the provisions of this Act should be made applicable to them.