D.C. Mun. Regs. tit. 25-C, § 6419
6419.1 An atmospheric break or approved back flow prevention device shall be provided in each pool water supply line that is connected to a public water supply.
6419.2 Vacuum breakers shall be installed on all hose bibbs.
SOURCE: Final Rulemaking published at 55 DCR 012845 (December 26, 2008).