The classification of the prospective bidder shall be effective 15 days after the receipt of the information specified in section 4 of this act and shall expire at such time after the effective date as specified in regulations promulgated by the commissioner. No person shall be qualified to bid on any contract who does not have a valid classification as to type and amount of work required by the contract, on the date set for the opening of bids for such contract.
N.J.S. § 27:7-35.5