D.C. Mun. Regs. tit. 19, § 1206
1206.1 All sightseeing tour companies or sightseeing tour guides shall furnish each person on a sightseeing tour with a card or ticket containing the following:
1206.2 The authorized person or office specified under § 1206.1(a) shall be available to receive complaints during the regular business hours of each day that sightseeing tours are conducted by the sightseeing tour company.
SOURCE: Final Rulemaking published at 57 DCR 6116 (July 16, 2010).