Section 275(2) in The West Bengal Motor Vehicles Rules, 1989
(2)If any person wishes to manufacture a producer the design of which contemplates departure from ordinary practice, the employment of any new or unusual methods of construction, or the use of methods of construction and processes not in conformity with these rules and specifications, he shall apply to the State Transport Authority stating in what respect the design departs from ordinary practice and the modification or relaxation of the rules and specification which he desires to be made, with the reasons thereof.
