PDFWAC 480-93-170
Tests and reports for gas pipelines.
(1) Each gas pipeline company must notify the commission in writing at least three business days prior to the commencement of any pressure test of a gas pipeline that will have a MAOP that produces a hoop stress of twenty percent or more of the specified minimum yield strength of the pipe used. Pressure test procedures must be on file with the commission or submitted at the time of notification.
(a) The pressure tests of any such gas pipeline built in Class 3 or Class 4 locations, as defined in 49 C.F.R. § 192.5, or within one hundred yards of a building, must be at least eight hours in duration.
(b) When the test medium is to be a gas or compressible fluid, each gas pipeline company must notify the appropriate public officials so that adequate public protection can be provided for during the test.
(c) In an emergency situation where it is necessary to maintain continuity of service, the requirements of subsection (1) of this section and subsection (1)(a) of this section may be waived by notifying the commission by calling the emergency notification line (see WAC 480-93-005(8)) prior to performing the test.
(2) The minimum test pressure for any steel service line or main, regardless of the intended operating pressure, must be determined by multiplying the intended MAOP by a factor determined in accordance with the table located in 49 C.F.R. § 192.619 (a)(2)(ii).
(3) Each gas pipeline company must perform pressure tests for all new or replacement gas pipeline installations.
(4) All service lines that are broken, pulled, or damaged, resulting in the interruption of gas supply to the customer, must be pressure tested from the point of damage to the service termination valve (generally the meter set) prior to being placed back into service.
(5) Each gas pipeline company may only use pretested pipe when it is not feasible to conduct a pressure test.
(6) Each gas pipeline company must perform soap tests at the tie-in joints at not less than the current operating pressure of the gas pipeline.
(7) Each gas pipeline company must keep records of all pressure tests performed for the life of the pipeline and must document the following information:
(a) Gas pipeline company's name;
(b) Employee's name;
(c) Test medium used;
(d) Test pressure;
(e) Test duration;
(f) Line pipe size and length;
(g) Dates and times; and
(h) Test results.
(8) Where feasible, each gas pipeline company must install and backfill plastic pipe prior to pressure testing to expose any potential damage that could have occurred during the installation and backfill process.
(9) When a gas pipeline company performs multiple pressure tests on a single installation, the gas pipeline company must maintain a record of each test. An example of a single installation with multiple tests would be any continuous on-going job or installation such as a new plat or long main installation where more than one pressure test was conducted during construction.
(10) Pressure testing equipment must be maintained, tested for accuracy, or calibrated, in accordance with the manufacturer's recommendations. When there are no manufacturer's recommendations, then pressure testing equipment must be tested for accuracy at an appropriate schedule determined by the gas pipeline company. Test equipment must be tagged with the calibration or accuracy check expiration date. The requirements of this section also apply to equipment such as pressure charts, gauges, dead weights or other devices used to test, monitor or check system pressures or set-points.
[Statutory Authority: RCW 80.01.040, 80.04.060 and 81.88.040. WSR 08-12-046 (Docket PG-070975, General Order R-549), § 480-93-170, filed 5/30/08, effective 6/30/08. Statutory Authority: RCW 80.01.040, 81.01.010, and 81.88.060. WSR 07-18-010 (Docket PG-061027, General Order R-544), § 480-93-170, filed 8/23/07, effective 9/23/07. Statutory Authority: RCW 80.04.160, 80.28.210, and 80.01.040. WSR 05-10-055 (Docket No. UG-011073, General Order No. R-520), § 480-93-170, filed 5/2/05, effective 6/2/05; Order R-28, § 480-93-170, filed 7/15/71; Order R-5, § 480-93-170, filed 6/6/69, effective 10/9/69.]