Ammonia Facility Pipe Colors and Labels
International Institute of Ammonia Refrigeration (IIAR) Bulletin No. 114 defines the pipe marking standard for ammonia refrigeration systems, building on the general requirements of ANSI/ASME A13.1.
Pipe Colors
High Pressure Liquid: Orange (Pantone 152C)
High Pressure Vapor: Yellow (Pantone 109C)
Low Pressure / High Temp (Liquid & Vapor): Light Blue (Pantone 298C)
Low Pressure / Low Temp (Liquid & Vapor): Dark Blue (Pantone 3015C)
Low Pressure / Low-Low Temp (Liquid & Vapor): Purple (Pantone 2617C)
Relief Vent Piping: Gray
Water / Glycol: Green