Recent Blog Posts

Decommissioned Pipes and Valves

February 4th, 2025

Question: Why is it important to remove decommissioned pipes and valves from an ammonia refrigeration system? Answer: To prevent an accidental release due to a pipe or flange leak. Consider a scenario where a ceiling-suspended evaporator is removed from a system. The ammonia pipes are cut and capped, and the evaporator unit is removed from […]

Ammonia Component Marker Requirements

October 1st, 2024

This is an update to a blog that was originally posted on 5/25/15. You can read the original blog here. New Ammonia Refrigeration Systems For new ammonia refrigeration systems, all vessels and equipment (compressors, condensers, etc.) must follow the component marker requirements in ANSI/IIAR 2-2021 §4.2. The standard states the following in regard to component […]

IIAR 6 Appendix B Pressure Vessels Checklist | Part 9

September 17th, 2024

Part 9: This is a continuation of our blog series explaining how to perform an IIAR 6 Appendix B inspection of an ammonia pressure vessel. Item Q asks the inspector to verify that the sight glass is adequately protected from traffic, equipped with 360° guards, and configured with internal check valves if the glass breaks. […]

Machinery Room Ventilation System Tests

August 6th, 2024

Machinery room ventilation systems have long been required by model codes and standards. Dating back to at least the 1967 Uniform Mechanical Code[1], refrigeration machinery rooms have been required to be configured with adequate ventilation in the event of a refrigerant release. While we have written previously about the current ventilation design, control, and testing […]

IIAR 6 Appendix B Pressure Vessels Checklist | Part 8

December 13th, 2023

Part 8: This is a continuation of our blog series explaining how to perform an IIAR 6 Appendix B inspection of an ammonia pressure vessel. Items M and N ask if the vessel certification drawings and manufacturer data report are on file. The data report, commonly referred to as a U-1 or U-1A form, we […]