No materials or services shall be furnished through any working capital fund except on requisition or purchase order chargeable to an appropriation with a sufficient unencumbered balance to pay the estimated cost thereof, or unless a special cash deposit has been made therefor. The controlling department head, in his discretion, may accept in lieu of a special cash deposit an agreement to reimburse the working capital fund for the cost of the materials or services. All requisitions and purchase orders involving intradepartment transactions shall be approved by the head of the department for propriety and sufficiency of the appropriation to which they are chargeable. All requisitions and purchase orders involving interdepartment transactions shall be likewise approved by the comptroller.
(Prior code § 7-24.7)