Pipe Welding Requirements for Gas Installations

Topic

CSA’s B149.1 Natural gas and propane installation code details pipe welding requirements for gas piping systems installed downstream of a gas company’s meter set or connected to a propane supply. Gas Safety Regulation section 4(3) further states that individuals must not perform welding on metallic gas piping unless they hold a Pressure Welder Certificate of Qualification. 

Important information

Under section 6.9 of CSA B149.1, gas piping of NPS 21/2” to 4” shall be joined either by press-connect fittings certified to CSA 6.32 (ANSI LC-4) or be welded. Piping greater than NPS 4” shall be joined by welding only. A registered welding procedure specification shall be prepared and qualified in accordance with ASME Boiler and Pressure Vessel Code Section IX and be performed by a welder registered under the applicable provincial or territorial legislation. 

Welded gas system procedures 

(1)   Gas piping installations that involve welding must be performed in accordance with a procedure registered with Technical Safety BC.

(2)   Welding procedures must be registered by the holder of an appropriate class of boilers, pressure vessels, and refrigeration (BPVR) contractor license. A licensed gas contractor can apply to become a BPVR contractor or obtain the services of the same to register the welding procedure and perform the welding on behalf of the gas contractor. 

(3)   The welder must hold an appropriate Welder Performance Qualification for the applicable registered welding procedure.

(4)   Acceptance criteria for welds shall be in accordance with clause 6.9.4 of CSA B149.1

(5)   The licensed BPVR contractor must supply documentation demonstrating compliance to sections: 1(1) - (4) above to the licensed gas contractor holding the gas installation permit. This information must be supplied to the area Technical Safety BC gas safety officer upon request for inspection.

(6)   Testing of the gas system shall be performed by the licensed gas contractor in accordance with requirements listed under section 6.22 of CSA B149.1.

(7)   Other non-pressure piping gas system installation and commissioning scope of work not detailed under this section, must be performed by a licensed gas contractor in accordance with all applicable requirements under the Gas Safety Regulation.

Vicky Kang
Manager, Energy
Provincial Safety Manager, Gas

References:
Gas Safety Regulation
Power Engineers, Boiler, Pressure Vessel and Refrigeration Safety Regulation
ASME Boiler and Pressure Vessel Code Section IX  
CSA B149.1 Natural Gas and Propane Installation Code