Gov. Code, § 25509

In any county which employs a purchasing agent the board of supervisors may by ordinance create and maintain a purchasing agent’s stores account for the purchase and maintenance of a stock of general supplies and materials for the county. The board shall determine the amount of said account and shall fix the same in the ordinance creating the account; said ordinance shall also prescribe the method of administration of the account and the manner of accounting therefor. The board may also by ordinance authorize the purchasing agent to establish a checking account in a bank for the payment of miscellaneous and emergency purchases of services and supplies by purchase order check not to exceed an amount fixed by such ordinance. The procedures for the issuance of such purchase order checks and the administration, including replenishment of such account, shall be established by resolution of the board. Any loss, not caused by negligence of any officer or employee of the county, incurred by reason of the issuance of any check on such checking account shall be charged against the general fund of the county. The authority of this section shall be in addition to and not a limitation upon any revolving fund of the purchasing agent otherwise provided for by law.