N.Y. Comp. Codes R. & Regs. tit. 19 § 425.5
Expenses and losses incurred in responding to a call for assistance pursuant to section 209 of the General Municipal Law, to the extent that they constitute firefighting costs and are otherwise eligible, may be claimed only if reimbursement pursuant to subdivision 2, 3 or 4 of such section is not claimed. Proper amounts paid by a city, town (in relation to territory in the town located in a fire protection district, fire alarm district or territory in the town outside any village, fire district, fire protection district or fire alarm district), village or fire district, pursuant to subdivision 2, 3 or 4 of section 209 of the General Municipal Law, as a result of a call for assistance, may be claimed to the extent such payments are for firefighting costs and are otherwise eligible.
N.Y. Comp. Codes R. & Regs. Tit. 19 § 425.5