47 C.F.R. § 68.7 Technical criteria for terminal equipment.
Title 47 - Telecommunication
(a) Terminal equipment shall not cause harm, as defined in §68.3, to the public switched telephone network. (b) Technical criteria published by the Administrative Council for Terminal Attachments are the presumptively valid technical criteria for the protection of the public switched telephone network from harms caused by the connection of terminal equipment, subject to the appeal procedures in §68.614 of this part. [66 FR 7581, Jan. 24, 2001]
Title 47: Telecommunication
PART 68—CONNECTION OF TERMINAL EQUIPMENT TO THE TELEPHONE NETWORK
Subpart A—General
§ 68.7 Technical criteria for terminal equipment.

