(a) New, altered, extended, or repaired systems. Every new plumbing and gas piping system and every part of an existing system that has been altered or repaired except for minor alterations and ordinary repairs, shall be tested as hereinafter prescribed to disclose leaks and defects. However, testing may be waived in the following cases:
(1) In any case that does not involve replacement, alteration, or relocation of any water supply, drainage, or vent piping.
(2) In any case where plumbing equipment may be set up temporarily for exhibition purposes.
(b) Representation at test.
(1) Tests required by section 27-922 of this article shall be conducted in the presence of the commissioner or an authorized plumbing inspector of the department.
(2) The commissioner may also authorize such test to be witnessed by architects, engineers, master plumbers or representatives of utility companies, each of whom must be acceptable to the commissioner. Persons performing this function shall have had at least five (5) years experience in inspection and testing of gas piping systems, or hold a current master plumbers license. Such tests may be conducted without any verifying inspection or tests by members of the department, provided that verified statements and supporting inspectional and test reports are filed with the department within one working day of such tests.
(c) Exposure of work. If any plumbing system or part thereof is enclosed before it has been inspected, tested, and accepted as prescribed in this subchapter, such system or part thereof shall be uncovered upon the direction of the commissioner.
(d) Retesting. If, upon inspection and tests, any of the work fails to meet the test requirements, the necessary corrections shall be made before any reinspections or retests are conducted.