Arizona Plumbing Practice Exam

In plumbing and gas piping installation, compliance with the National Fuel Gas Code and local regulations is critical for ensuring safety and functionality. For a 1/2 inch gas line tubing, the standard practice is to provide horizontal support at intervals that minimize sagging and stress on the piping. Supporting the tubing every 4 feet helps maintain its structural integrity and prevents potential leaks or damage due to excessive movement or weight.

This interval allows the gas line to be stable while accommodating thermal expansion and contraction, which is especially significant in materials like plastic and metal. Additionally, ensuring that the tubing is supported appropriately helps to reduce stress on fittings and connections, which can lead to maintenance issues if not addressed.

In contrast, longer support intervals such as 6 or 8 feet would not adequately ensure the stability of the tubing, potentially leading to safety hazards or code violations. Therefore, providing support every 4 feet is the correct standard for installing 1/2 inch gas line tubing.