What is required for pipe that is under air pressure within a system?

• A. The pipe must resist corrosion.
• B. The pipe must be painted red.
• C. The pipe must be insulated.
• D. The pipe must be routed through unheated areas.

Answer: (A)

When pipe in a sprinkler system is under air pressure, it isn’t constantly in contact with water, which can leave moisture and oxygen available to cause corrosion over time. Because of that, the pipe must resist corrosion to maintain the system’s integrity and reliability. This means using materials or protective finishes that are corrosion-resistant, such as suitable metals with coatings or corrosion-resistant plastics, depending on the design and approvals.

Other options like painting for color, insulation, or routing through unheated areas don’t address the corrosion risk created by air-filled piping, so they aren’t required reasons for this scenario.