PDFWAC 480-93-115
Casing of line pipes.
(1) Whenever a gas pipeline company installs a steel line pipe in a casing, the casing must be bare steel.
(2) For casings installed after September 5, 1992, each gas pipeline company must attach separate test lead wires to each casing without vents, and to the steel gas pipeline to verify that no electric short exists between the two, and that an adequate level of cathodic protection is applied to the steel line pipe.
(3) Whenever a gas pipeline company installs a main or transmission line in a casing or conduit of any type material, the gas pipeline company must seal the casing ends to prevent or slow the migration of gas in the event of a leak.
(4) Whenever a gas pipeline company installs a service line in a casing or conduit, the gas pipeline company must seal the casing at the end nearest the building wall to prevent or slow the migration of gas towards the building in the event of a leak.
[Statutory Authority: RCW 80.01.040, 80.04.060 and 81.88.040. WSR 08-12-046 (Docket PG-070975, General Order R-549), § 480-93-115, filed 5/30/08, effective 6/30/08. 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), § 480-93-115, filed 5/2/05, effective 6/2/05. Statutory Authority: RCW 80.01.040. WSR 92-16-100 (Order R-375, Docket No. UG-911261), § 480-93-115, filed 8/5/92, effective 9/5/92.]