Part 52. PART 52—NUMBERING

• SUBPART A [§ 52.1 - § 52.5] - Subpart A—Scope and Authority
• SUBPART B [§ 52.7 - § 52.19] - Subpart B—Administration
• SUBPART C [§ 52.20 - § 52.99] - Subpart C—Number Portability
• SUBPART D [§ 52.101 - § 52.111] - Subpart D—Toll Free Numbers
• SUBPART E [§ 52.200 - § 52.202] - Subpart E—Universal Dialing Code for National Suicide Prevention and Mental Health Crisis Hotline System