D.C. Mun. Regs. tit. 11, § 702
702.1 A mechanical amusement machine shall be permitted in a C-1 District as an accessory use incidental to the uses permitted in §§ 701 through 711; provided, that the machine shall be subject to the provisions of § 2501.
702.2 A child development home shall be permitted in a C-1 District as an accessory building and use incidental to the uses permitted in §§ 701 through 711; provided:
(a) The dwelling unit in which the use is located shall be the principal residence of the caregiver; and
(b) The use otherwise shall meet the definition of a home occupation.
702.3 An elderly day care home shall be permitted in a C- 1 District as a matter of right as an accessory use incidental to the uses permitted in §§ 701 through 711; provided:
(a) The dwelling unit in which the use is located shall be the principal residence of the caregiver; and
(b) The use otherwise shall meet the definition of a home occupation.
702.4 Other accessory uses customarily incidental and subordinate to the uses permitted in C-1 Districts shall be permitted in a C-1 District, except that a firearms retail sales establishment shall not be permitted as a principal or an accessory use.
SOURCE: § 5101.6 of the Zoning Regulations, effective May 12, 1958; as amended by: Final Rulemaking published at 29 DCR 4913, 4915 (November 5, 1982); Final Rulemaking published at 46 DCR 8284, 8288 (October 15, 1999); and Final Rulemaking published at 47 DCR 9741-43 (December 8, 2000), incorporating by reference the text of Proposed Rulemaking published at 47 DCR 8335, 8391 (October 20, 2000).