UPC 1208: Approved Fuel Gas Piping Materials

Section 1208 is titled "Gas Piping System Design, Materials, and Components." It sets the design, the legal materials, and the parts for a fuel gas piping system. A subsection titled "1208.6 Acceptable Piping Materials and Joining Methods" lists what you can use and how to tie it together. The material you pick decides the joints you must use.

The code approves several materials. Steel and iron are the classic choice. A heading titled "1208.5.2.2 Steel and Wrought-Iron" covers them. This is the black pipe most people picture for a gas line. It is joined with threaded fittings.

Copper and copper-alloy tube are allowed in some cases. Gas that carries certain compounds can attack copper, so the code limits where copper may be used based on the gas.

Corrugated stainless steel tubing is another option. A heading titled "1208.5.3.4 Corrugated Stainless Steel" covers it. This flexible tubing, often called CSST, is quick to route through a building. It must be bonded to the electrical ground for safety.

Aluminum alloy appears too. A heading titled "1208.5.2.4 Aluminum Alloy" covers it, with limits on where it can go.

For gas run underground to a building, plastic pipe is common. Polyethylene, or PE, is used for buried service lines outside. The code sets where PE is allowed and how it is joined. These plastic rules are described here, not quoted, so confirm the exact subsection before you rely on it.

Picking the pipe is only half the job. Each material has approved joints. Steel is threaded or welded. Copper tube uses approved fittings. CSST uses its own listed fittings. PE is heat-fused or uses special fittings. A mixed run, like steel tied to copper, has its own rules. Bottled gas gets extra attention. A heading titled "1208.6.11.4 Liquefied Petroleum Gas Piping Systems" covers LP-gas.

This section governs any new gas line or gas line change. Picture adding a line for a range, a dryer, a pool heater, or a fire pit. The plumber picks an approved material for the run, indoor or underground, and joins it the approved way. An inspector checks the material and the joints before the line is charged with gas.

Choosing between black iron and CSST is a common question on a new line. Both are approved when installed right. See CSST vs black iron gas pipe and cost to add a gas line. For how gas pipe is installed, see UPC 1210 gas piping installation. For how it is pressure tested, see UPC 1213 fuel gas piping testing. Because a gas leak is dangerous, a licensed plumber should choose and join the pipe. See our gas line service if you are planning a new line.

Section 1208 is part of the Uniform Plumbing Code, published and copyrighted by IAPMO. The up.codes viewer shows the section headings, so the headings above are quoted and the rules are paraphrased, not copied. The full list of materials, limits, and joining methods lives in the code text, including subsections for plastic and underground pipe that are described here, not quoted. Phoenix enforces the 2024 UPC with local amendments, so confirm the current materials and numbers. Read Chapter 12 on UpCodes or the official 2024 UPC, and check local amendments at phoenix.gov/pdd.