Sec.  12.2   Backup power.

   Local  exchange  carriers (LECs), including incumbent LECS (ILECs) and
   competitive  LECs  (CLECs), and commercial mobile radio service (CMRS)
   providers must have an emergency backup power source for all assets that are
   normally powered from local AC commercial power, including those inside
   central offices, cell sites, remote switches and digital loop carrier system
   remote terminals. LECs and CMRS providers should maintain emergency back-up
   power for a minimum of 24 hours for assets inside central offices and eight
   hours for cell sites, remote switches and digital loop carrier system remote
   terminals that are normally powered from local AC commercial power. LECs
   that meet the definition of a Class B company as set forth in  Sec. 32.11(b)(2)
   of the Commission's rules and non-nationwide CMRS providers with no more
   than 500,000 subscribers are exempt from this rule.

   Effective Date Note:   At  72 FR 37673 , July 11, 2007,  Sec. 12.2 was added,
   effective Aug. 10, 2007. At  72 FR 44978 , Aug. 10, 2007, the addition was
   delayed until Oct. 9, 2007.