(a) Cross connections between safe and unsafe water supply distributing systems shall not be permitted unless such connections have the written approval of the Division of Public Health.
(b) No plumbing, fixture, construction, valves, fitting, device, apparatus or connection that will provide a cross connection between a safe water supply and a sewage system or will permit or make possible the back flow of sewage or waste into a water supply system shall be installed.
Structure Delaware Code
Chapter 79. BASIC PLUMBING PRINCIPLES
§ 7902. Principles applicable throughout State.
§ 7903. Plumbing Code; adoption and enforcement.
§ 7905. Additional regulations.
§ 7907. Inspection and inspectors.
§ 7910. Cross connections with unsafe water supplies.
§ 7911. Adequate water supply.
§ 7913. Hot water tanks or boilers.
§ 7914. Separate sewer connections.
§ 7915. Family private water closet in multiple dwellings.
§ 7916. Plumbing fixture materials.
§ 7917. House drainage system.
§ 7919. Cleanouts in drainage systems.
§ 7921. Adequate air circulation.
§ 7922. Roof terminals, soil or waste stacks.
§ 7923. Water or air pressure test.
§ 7924. Substances entering house drainage system.
§ 7925. Connections with refrigerators.
§ 7926. Light and ventilation.
§ 7927. Private sewage treatment and disposal system.