Labour act covering wages and overtime pay - exemption rule?

I am not sure about the labour act covering wages and overtime pay. My exposure to things related to statutory requirements covering personnel policies is very limited. From what I have observed, administration and management staff (even assistants like accounts or administration assistant) are generally not paid overtime pay. I do not know if the law doesn’t mandate it or it is just a practice. However workers are paid overtime at 2 times their regular pay.
Kindly explain any one.

White collar employees like accountants, cashier, clerks, stenographers and/or typists, receptionists etc either employed in separate offices or offices attached to the factory premises are also persons employed or workmen under the respective establishment-specific labor law as the case be and the Industrial Disputes Act,1947. They are, therefore certainly entitled to over time wages as per the law applicable to them when they are required to work beyond their normal working hours. It may be just a practice not to make any statutory claim for O.T wages either because of their loose schedule of work or because of the degree of closeness to the higher echelons of the organizational hierarchy and the confidentiality they enjoy.