Which type of copper tubing is identified by the color green?

Copper tubing is categorized into different types based on its wall thickness and intended use, with each type often color-coded for easy identification. Type K copper tubing, which is identified by a green color, is the thickest of the common types, making it suitable for underground applications and where high pressure is a concern, such as in certain plumbing and heating situations.

Type K tubing is used for water service lines, fire protection systems, and other applications where durability and resistance to external conditions are required. The green color helps differentiate it from other types, like Type L (red), Type M (blue), and DWV (drain, waste, and vent). Recognizing these color codes allows plumbers and technicians to quickly determine the appropriate type of tubing for any given job, ensuring safety and compliance with plumbing standards.