DIY Natural Gas Lines: Is Galvanized Pipe Permitted? Find Out Now

When it comes to natural gas piping, safety is paramount. One of the most important considerations is the type of pipe material used. Galvanized pipe has been widely used in the past, but its suitability for natural gas lines raises concerns. This article delves into the question of whether galvanized pipe can be used for natural gas lines, exploring its advantages, disadvantages, and safety implications.

What is Galvanized Pipe?

Galvanized pipe is steel pipe coated with a layer of zinc to protect it from corrosion. The zinc coating forms a barrier between the steel and the surrounding environment, preventing rust and other forms of deterioration.

Advantages of Galvanized Pipe

• Corrosion resistance: The zinc coating provides excellent protection against corrosion, making galvanized pipe suitable for outdoor and underground applications.
• Durability: Galvanized pipe is highly durable and can withstand harsh conditions, including exposure to moisture, chemicals, and extreme temperatures.
• Cost-effectiveness: Galvanized pipe is relatively inexpensive compared to other pipe materials, making it a cost-effective option for large-scale projects.

Disadvantages of Galvanized Pipe

• Zinc embrittlement: Over time, the zinc coating can react with the steel, causing the pipe to become brittle and susceptible to cracking. This is particularly concerning in high-pressure applications.
• Reaction with natural gas: Natural gas contains sulfur compounds that can react with the zinc coating, forming zinc sulfide. This can lead to the formation of deposits inside the pipe, reducing flow and increasing the risk of blockages.
• Hydrogen embrittlement: Hydrogen gas can be produced during the corrosion process, which can diffuse into the steel and cause embrittlement. This can weaken the pipe and increase the risk of failure.

Safety Considerations

The safety implications of using galvanized pipe for natural gas lines are significant. Zinc embrittlement, reaction with natural gas, and hydrogen embrittlement can all compromise the integrity of the pipe and pose a serious safety hazard.

National Fuel Gas Code (NFPA 54)

The National Fuel Gas Code (NFPA 54) is the primary safety standard for the installation and maintenance of natural gas piping systems. NFPA 54 prohibits the use of galvanized pipe for natural gas lines larger than 2 inches in diameter and operating at pressures exceeding 5 psi.

Alternatives to Galvanized Pipe

Due to the safety concerns associated with galvanized pipe, alternative materials are recommended for natural gas lines. These alternatives include:

• Black iron pipe: Black iron pipe is made of steel and coated with a layer of black oxide to protect it from corrosion. It is stronger and more resistant to zinc embrittlement than galvanized pipe.
• Copper pipe: Copper pipe is highly corrosion-resistant and does not react with natural gas. It is the preferred choice for indoor natural gas lines.
• Polyethylene pipe (PE): PE pipe is a flexible plastic pipe that is highly resistant to corrosion and hydrogen embrittlement. It is suitable for underground natural gas lines.

When Can Galvanized Pipe Be Used?

While galvanized pipe is generally not recommended for natural gas lines, there are some limited exceptions:

• Small-diameter lines: Galvanized pipe may be used for small-diameter natural gas lines (less than 2 inches) operating at low pressures (less than 5 psi).
• Temporary installations: Galvanized pipe may be used for temporary natural gas lines, such as those used for construction or testing purposes.

Recommendations: Safety First

When it comes to natural gas piping, safety should always be the top priority. While galvanized pipe may have some advantages, its susceptibility to zinc embrittlement, reaction with natural gas, and hydrogen embrittlement make it unsuitable for most natural gas line applications. Alternative materials, such as black iron pipe, copper pipe, or polyethylene pipe, are safer and more reliable choices.

What People Want to Know

Q: Can I use galvanized pipe for my home’s natural gas line?
A: No, galvanized pipe is not recommended for home natural gas lines due to safety concerns. Black iron pipe or copper pipe are better choices.

Q: What are the signs of zinc embrittlement in galvanized pipe?
A: Signs of zinc embrittlement include cracking, reduced ductility, and a brittle appearance of the pipe.

Q: Can galvanized pipe be used for outdoor natural gas lines?
A: Galvanized pipe may be used for small-diameter outdoor natural gas lines operating at low pressures, but it is not recommended for large-diameter or high-pressure lines.