712.2, Water Test, is hereby deleted in its entirety and the following provisions shall be substituted therefor:

Water test for drain, waste and vent. The water test shall be applied to the drainage and vent system either in its entirety or in sections. If applied to the entire system, all openings in the piping shall be tightly closed, except the highest opening, and the system filled with water to a point of overflow. If the system is tested in sections, each opening shall be tightly plugged except the highest opening of the section under test, and each section shall be filled with water, but no section shall be tested with less than five (5) feet (1.5 m) head of water. In testing successive sections, at least the upper five (5) feet (1.5 m) of the next preceding section shall be tested, so that no joint or pipe in the building (except the uppermost five (5) feet (1.5 m) of the system) shall be submitted to a test of less than five (5) feet (1.5 m) head of water. The water test shall be kept in the system, or in the portion under test, for at least fifteen (15) minutes before the inspection starts. The system shall then be tight at all points.