D.C. Mun. Regs. tit. 9, § 401
401.1 Persons who furnish a nontaxable service are considered consumers of all materials and supplies purchased to operate that business.
401.2 Persons who furnish non-taxable services must reimburse the vendors from whom they purchase materials and supplies for the sales tax.
SOURCE: Commissioners' Order 54-1415, 1 DCR 4 (July 19, 1954).