Section 3(12) in The National Highways Rules, 1957
(12)Classification of contractors.(a)The executing agency shall ensure that contractors are classified for jobs of various sizes, taking into consideration, employment of qualified engineers, kind of machinery and expertise available with them and the total workload which they can handle at a given time;(b)The contractors for works of intricate nature or costing more than a specified amount a specified from time to time by the Central Government shall be considered for prequalification.
