Ill. Admin. Code tit. 83, § 411.110 – Record-Keeping Requirements

a) Required records. Except as provided in subsection (b) below, a jurisdictional entity shall maintain, for the most recent five-year period, the records listed below.
1. 1) Records sufficient to determine a history of electric service interruptions experienced by each customer at the customer's current location. The records shall be sufficient to determine the information listed below for each interruption.
  1. A) Starting date of the interruption.
  2. B) Starting time of the interruption.
  3. C) Interruption duration.
  4. D) Description of the cause of the interruption.
  5. E) Operating areas affected.
  6. F) Circuit number(s) of the distribution circuit(s) affected.
  7. G) Number of customers affected.
  8. H) Service account number of each customer affected.
  9. I) Address of each affected customer location.
  10. J) Name of each affected customer's electric energy supplier, if known.
2. 2) Records showing, for each distribution circuit, the total number of customers served by the circuit at the end of each year.
b) Periods for which records are not required. A jurisdictional entity need not maintain records reflecting the information identified in subsection (a) for any period prior to calendar year 1994. A jurisdictional entity that, as of January 1, 1994, did not have the technical capability to collect and record some or all of the information identified in subsection (a) need not maintain records reflecting such information for any period prior to January 1, 1999. A jurisdictional entity serving retail customers in Illinois as of December 16, 1997, and that was exempted from the requirements of the Commission's electric service reliability policy (83 Ill. Adm. Code 410, Subpart C) as of that date, need not maintain records reflecting such information for any period prior to January 1, 2002.