Which materials are prohibited for use in fire service mains?

Galvanized steel is prohibited for use in fire service mains due to its susceptibility to corrosion over time, which can severely compromise the plumbing system's integrity. When galvanized steel is exposed to water, especially in a fire protection setting where it may carry higher pressures and varied water quality, the zinc coating can deteriorate and lead to rust formation. This corrosion can result in leaks, reduced water flow, and potential system failures when rapid response is essential during a fire emergency.

In comparison, the other materials listed, such as stainless steel, polyethylene, and copper, are considered suitable for fire service mains. Stainless steel offers excellent corrosion resistance and strength, making it a durable choice. Polyethylene is favored for its flexibility and resistance to certain chemicals, while copper is valued for its durability and ability to withstand varying environments without significant degradation. Thus, understanding the limitations and appropriate applications of each material is crucial in designing and installing reliable fire service mains.