258.6 Hydrostatic testing.

(a)Each new, reconstructed, relocated, replaced, or reactivated segment of pipeline must be hydrostatically tested in accordance with this section to substantiate the current or proposed maximum operating pressure. Any pipeline, or segment thereof, for which the maximum operating pressure is to be increased must also be tested in accordance with this section.#

(b)Notwithstanding the requirements of 49 CFR 195.302(c), the minimum test pressure at the lowest point of the test section shall be the lesser of:#

(1)150 percent of the maximum operating pressure; or#

(2)the pressure that produces a pipe stress equivalent to 90 percent of the specified minimum yield strength of the pipe.#

(c)Except as provided in subdivision (d) of this section, the test pressure must be maintained throughout the pipeline segment for at least 12 hours following stabilization.#

(d)For a short segment of pipeline (100 feet or less) which is completely exposed and where its entire circumference may be readily examined visually for the detection of leaks, the test duration shall be at least four hours following stabilization and the test shall precede coating of the welds.#

(e)A calibrated recording pressure gauge that indicates increments of five pounds per square inch or less shall be attached to the test section. The gauge must be calibrated at least hourly for the first and last two hours of the test. Calibration is against a dead-weight tester attached to the test section.#

(f)At least five business days prior to starting a test, the corporation shall notify the office of gas and water of the department in Albany in writing. In order to maintain continuity of service during emergencies, shorter notice is permissible. The corporation shall also notify the officials of the municipalities wherein the test is to be conducted. Tests conducted under this section are not deemed satisfactory unless certified by an inspector of the office of gas and water of the department.#