Class A. Utilities having annual steam operating revenues of $750,000 or more. Such utilities shall keep all the accounts prescribed herein which are applicable to their operations.
Class B. Utilities having annual steam operating revenues of more than $100,000 but less than $750,000. Such utilities shall keep all the accounts prescribed herein which are applicable to their operations, except those operation and maintenance accounts in which the letter B does not appear in the prefix.
N.Y. Comp. Codes R. & Regs. Tit. 16 § 461.1