Approvals required to set up Diesel generator

At our site in Gujarat, we are in the process of installing Diesel generator of 3000 KVA for emergency purpose only. Do I have to obtain any approval from Electricity board, pollution control board or any certificate from third party?
If yes, also request to send written requirement of Statutory body.
Please help me.
Thanking you in advance.

Yes

Clearance / approval is needed from State Electricity department (or Electricity Regulatory Board or the Power Distribution Company, depending on the local regulations), Pollution Control Board (it should be in the Consent to Operate)

The Pollution Control Board approval is needed before you actually use the DG Set or more correctly, once it is ready for use, irrespective of whether you use it or not.