(10)The Central Government may, after making such inquiry as it may think fit, direct, by notification in the Official Gazette, that the exemption conferred by this section shall not apply to any class of industrial undertakings with effect from such date as it may specify in the notification.] [Inserted by Act 44 of 1980, Section 16 (w.e.f. 1.4.1981).][ Inserted by Act 11 of 1983, Section 23 (w.e.f. 1.4.1984).][Inserted by Act 44 of 1980, Section 16 (w.e.f. 1.4.1981).]