When is nonmetallic pipe allowed to be used in NH3 applications?

Nonmetallic pipe is generally not permitted for use in ammonia (NH3) applications due to the chemical's corrosive properties and the specific requirements for safety and reliability in handling ammonia systems. The material compatibility with ammonia is critical because nonmetallic materials may not withstand the chemical's effects, potentially leading to failures or leaks that can pose serious safety hazards.

The use of nonmetallic pipe would not be acceptable under any circumstances in ammonia applications because it could compromise the integrity of the system. Understanding the properties of ammonia and the materials used in piping is key to maintaining safety and functionality in high-pressure piping systems. Therefore, nonmetallic pipe is never an allowable option for NH3 applications, ensuring compliance with safety standards and regulations.