Ammonia systems designed to operate below -20 degrees F must comply with which standards?

The correct choice is based on the specific requirements for ammonia piping systems, particularly those that function at low temperatures. Ammonia systems intended to operate below -20 degrees Fahrenheit fall under the jurisdiction of ANSI B31.5, which provides guidelines for the design, fabrication, testing, and inspection of refrigerated piping systems, including those carrying ammonia.

This standard addresses the unique challenges associated with low-temperature service and the specific material and design considerations necessary for safe operation in such conditions. Additionally, the inclusion of ASME B31.5 signifies that compliance with both standards is appropriate, ensuring that both the design and operational aspects are adequately covered.

By conforming to these standards, operators can ensure the safety, integrity, and reliability of the ammonia systems, particularly in environments where extreme temperatures can significantly affect material properties and system performance.