Okla. Stat. tit. 63 § 695.9
Any jurisdiction rendering aid in another jurisdiction pursuant to the Oklahoma Intrastate Mutual Aid Compact shall be reimbursed by the jurisdiction receiving such aid for any loss or damage to or expense incurred in the operation of any equipment and the provision of any service in answering a request for aid and for the costs incurred in connection with such requests; provided, that any aiding jurisdiction may assume in whole or in part such loss, damage, expense, or other cost, or may loan such equipment or donate such services to the receiving jurisdiction without charge or cost; and provided further, that any two or more jurisdictions may enter into supplementary agreements establishing a different allocation of costs among those jurisdictions. Compensation expenses shall not be reimbursable under this section.
Okla. Stat. tit. 63, § 695.9