Cal. PUC § 13151.17

The board may provide for the making of contracts, or the placing of orders, for the engraving or printing of any bonds, whether definitive or temporary, or of interim receipts, authorized by this chapter, or for any printing incident to the offering or issuance of any such bonds, without advertising for bids, in any case where, because of limitations of time, or requirements as to quality of work, or as to security in the control or custody of plates, or any similar cause, the board may deem it to be in the public interest so to do, anything in this division to the contrary notwithstanding, but in so doing the board shall, if practicable, obtain or cause to be obtained competitive bids, formal or informal, from bidders who can perform work of the required quality within the required time, and, in the case of engraving, who are of proper responsibility and who have adequate facilities for the control and safekeeping of the engraved plates.