State agencies are authorized to advance funds to defray charges for materials to be furnished or services to be rendered by other state agencies. Such advances shall be made only upon the approval of the director of financial management, or his or her order made pursuant to an appropriate regulation requiring advances in certain cases. An advance shall be made from the fund or appropriation available for the procuring of such services or materials, to the state agency which is to perform the services or furnish the materials, in an amount no greater than the estimated charges therefor.
RCW 39.34.150