This information is provided free of charge by the Department of Industrial Relations from its web site at These regulations are for the convenience of the user and no representation or warranty is made that the information is current or accurate. See full disclaimer at

Subchapter 7. General Industry Safety Orders
Group 10. Gas Systems for Welding and Cutting
Article 85. Service Piping for All Gases

Return to index
New query

§4821. Gas Systems Piping for Welding and Cutting, Materials and Design.

(a) Piping and fittings shall comply with Chapters 1 through 4 of the American National Standard Code for Pressure Piping, ASME B31.1.2001, Power Piping, which is hereby incorporated by reference, insofar as it does not conflict with (b) and (c).

(b) Pipe shall be at least Schedule 40 and fittings shall be at least standard weight in sizes up to and including 6-inch nominal.

(c) Copper tubing shall be Types K or L in accordance with the Standard Specification for Seamless Copper Water Tube, ASTM B88-96 which is hereby incorporated by reference.

(d) Piping shall be steel, wrought iron, brass or copper pipe, or seamless copper, brass or stainless steel tubing, except as provided in Sections 4822 and 4823.

(e) Service piping systems shall be protected by pressure relief devices set to function at not more than the design pressure of the systems and discharging upwards to a safe location.


Authority cited: Section 142.3, Labor Code. Reference:Section 142.3, Labor Code.


1. New section filed 5-16-75; effective thirtieth day thereafter (Register 75, No. 20).

2. Amendment filed 7-16-76; effective thirtieth day thereafter (Register 76, No. 29).

3. Amendment of subsections (a), (c) and (e) filed 6-12-87; operative 7-12-87 (Register 87, No. 26).

4. Amendment of subsection (c) filed 1-6-99; operative 2-5-99 (Register 99, No. 2).

5. Amendment of subsection (a) filed 6-2-2003; operative 7-2-2003 (Register 2003, No. 23).

Go BackGo Back to Article 85 Table of Contents