IIAR 2-2021: Bulletin No. 114, and Labeling

IIAR Bulletin No. 114 has been an important resource for the ammonia refrigeration industry since the early 1990’s. In the 2021 edition of IIAR Standard 2, the entirety of Bulletin No. 114 is incorporated as informative Appendix Q. This means that IIAR’s guidance on ammonia refrigeration labeling will no longer be available through a standalone publication, but rather will require referring to Standard 2 or the Refrigeration Piping Handbook, where it is also included as an appendix.

We’ve written about pipe labeling in the past, but here’s a quick summary of what is recommended in ANSI/IIAR 2-2021 Appendix Q.

Pipe Markers

Each pipe marker should contain the following:

• The pipe marker color should be Safety Orange
• The word ‘AMMONIA’ should be printed in black letters
• The physical state ‘LIQ’ or ‘VAP’ should be printed in the colors displayed below.
• The relative pressure ‘HIGH’ or ‘LOW’ should be printed in the colors displayed below. 70 psig is the cutoff between high and low pressure.
• The service abbreviation should be printed in black letters. Common abbreviations include:
  • CD: Condenser Drain
  • HPL: High Pressure Liquid
  • HTRL: High Temperature Recirculated Liquid
  • HTRS: High Temperature Recirculated Suction
  • HTS: High Temperature Suction
  • HGD: Hot Gas Defrost
  • RV: Relief Vent
• A flow direction arrow should indicate the direction of flow in the pipe.

Appendix Q suggests that pipe markers should be proportionate to the pipe diameter. Table 1 in Appendix Q has recommended marker sizes for various pipe diameters.

Pipe Color Scheme

Appendix Q recommends that ammonia pipes be color coded to assist personnel in quickly identifying the ammonia state, pressure range, and temperature range. IIAR recommends the following colors be used:

• High Pressure Liquid: Orange (Pantone 152C)
• High Pressure Vapor: Yellow (Pantone 109C)
• Low Pressure / High Temperature Liquid and Vapor: Light Blue (Pantone 298 C)
• Low Pressure / Low Temperature Liquid and Vapor: Dark Blue (Pantone 3015 C)
• Low Pressure / Low-Low Temperature Liquid and Vapor: Purple (Pantone 2617 C)

Component Markers

Each major component should also be clearly labeled. Component markers should include:

• Name of the equipment (e.g. Receiver 1, Accumulator 2, etc.)
• The marker color should be Safety Orange
• The letters should be printed in black letters
• Component markers should be 3-1/2” wide and long enough to accommodate the name of the component
• Lettering should be 2-1/2” high

Reference Chart

Since Appendix Q is nonmandatory, the content in §8.0 is important, especially if a facility chooses to deviate from what IIAR recommends.

“A reference chart that fully explains the ammonia refrigeration piping and component identification markers, including the approved abbreviations, should be placed in areas that are conspicuous to operating personnel. Regardless of the piping color scheme selected, a legend or key to the meaning of the colors should be posted in a conspicuous area. The reference chart, legend, or key should be made of durable material that will remain legible.”