N.Y. Comp. Codes R. & Regs. tit. 9, § 1647-4.2
(a) In addition to replacements, other expenditures in the nature of repairs, maintenance and renewals (RM&R) may be made to maintain or restore the utility, function or revenue producing capacity of a project. Such expenditures, however, are charged to expense, whereas expenditures for replacements are charged to the reserve. Theoretical criteria for distinguishing between RM&R on the one hand, and replacements, on the other, have been stated in the preamble to the definitions of the 4400, Repairs and Maintenance, group of expense accounts (see Part 1641). In view of the practical difficulties in their application, the division does not prescribe the use of such criteria, except as a guide, and bases its classification on a system of selection and predetermination, as follows: