Information Bulletin: Pipe welding requirements for gas installations



Reference number
IB-GA 2014-01
Revision Number
Revision 1


The CSA B149.1 Natural Gas and Propane installation code includes a welding requirement for joints in piping systems downstream of a gas company’s meter:

6.9.3 -Welding of gas piping shall be performed in accordance with a procedure and by an operator registered under the applicable provincial or territorial legislation.

In order to comply with the above section, an individual must be the holder of a pressure welder's certificate of qualification as issued under the Power Engineers, Boiler, Pressure Vessel and Refrigeration Safety Regulation:

6.9.4 -The acceptance criteria for any welds shall be as specified in Clause 7.10.2 of CSA Z662.

Important Information

Welds subject to the requirements of B149.1 require visual inspection only. Any imperfections are to be evaluated in accordance with CSA Z662 clause 7.11.

Welding requirements for distribution and service piping upstream of a gas company’s meter must be in accordance with CSA Z662 Clause 12.7. Welders must be qualified in accordance with Clause 12.7.3 and are not required to be holders of pressure welder's certificate of qualification. The inspection requirements and acceptance criteria for welded joints in distribution and service piping shall be as specified in CSA Z662 Clause 12.7.4

In general CSA Z662 section 12.7.4 describes the standards of acceptability for non-destructive inspection for arc and gas welding. These standards of acceptability shall apply to the determination of the acceptability of indications of imperfections of the size and type located by radiography and other non­destructive inspection methods other than ultrasonic inspection. 

Requirements specified for welds made to join pipe shall also apply to welds made to join components.

Such standards of acceptability are intended as a measure of adequate welding competence for production welds, as performed in accordance with qualified welding procedure specifications.



Brad Wyatt
Provincial Safety Manager, Gas



Safety Standards Act
Gas Safety Regulation
CSA B149.1 Natural gas and propane installation code
CSA Z662 Oil and Gas Pipe Systems