D.C. Mun. Regs. tit. 25-E, § 608
608.1 All licenses, Certificate of Occupancy, certifications, Department posted directives, and current inspection results shall be conspicuously posted near the entrance of the barber, cosmetology, or personal grooming facility, except professional certifications which may be worn or displayed at the station.
SOURCE: Final Rulemaking published at 68 DCR 013026 (December 10, 2021).