47 CFR § 68.7
Technical criteria for terminal equipment
February 16, 2021
(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]