Illinois Administrative Code
Title 83 - PUBLIC UTILITIES
Part 1326 - REQUIREMENTS FOR PRIVATE BUSINESS SWITCH SERVICE TO COMPLY WITH THE EMERGENCY TELEPHONE SYSTEM ACT
Subpart B - STANDARDS OF SERVICE
Section 1326.200 - General Standards and Requirements

The digits "9-1-1" shall be the primary emergency telephone number within a county or municipality that has received Commission or Department authority to operate as a 9-1-1 system. In areas where Enhanced 9-1-1 is available, a private business switch operator must ensure that its system is capable of meeting the requirements set forth in Section 1326.205. Nothing in this Section shall require changes in customary dialing patterns (i.e., using the prefix or access code 9 to obtain an outside line before dialing 9-1-1) for those PEAPs that are exempt pursuant to ETSA Section 15.8.