IIAR Commissions Research Project on Internal Relief Valves in Ammonia Refrigeration

The Natural Refrigeration Review Magazine recently published an article, Internal Relief Valves: Defining a Replacement Interval, on a major industry research project being carried out by ioMosaic. The project directly addresses concerns raised by federal regulators — including OSHA inspectors — who have challenged the long-held assumption that internal relief valves that discharge back into an ammonia refrigeration system will never fail to open. While ANSI/IIAR 6 specifies requirements for safety relief valves that discharge to the atmosphere, the standard is essentially silent on valves that relieve back into the system.

Rather than adopting an arbitrary replacement interval or copying standards from another industry, the International Institute of All-Natural Refrigeration (IIAR) commissioned ioMosaic to evaluate whether these valves fail and to establish an appropriate testing or replacement interval using predictive analysis engineering methods. Through this research, our analysis will estimate failure rates of internal relief valves by examining a broad sample of donor valves contributed by operating facilities. The study aims to determine corrosion rates and measure performance across both liquid and vapor donor valves from all types of facility conditions. “We want to try to determine how long a valve can survive and still be in good service so we [will] look at that data and develop standard deviations,” said David Blake, Senior Safety and Risk Management Consultant at ioMosaic.

In order to successfully define an evidence-based replacement interval and close an open gap in the code, IIAR Associate Technical Director Matt Chojnacki is overseeing the internal collection of donor relief valves on behalf of IIAR, especially those that have been in place longer and have more wear to examine.

“I want to call on anyone who can participate to send us their old internal relief valves,” said Chojnacki. “Ultimately, the more data we can yield around this subject, the better it is for our industry. As a driver of this data, IIAR can go back to OSHA and EPA with more than just a gut feel or a disagreement.”

IIAR is actively encouraging member participation by offering incentives, including free registration to the IIAR Annual Conference and covered shipping costs for donor valves. By gathering robust, real-world data points, this initiative provides the industry and regulators with actual proof to support safety standards grounded in technical fact.

Read the Full Article

Key Regulatory Standards

Facilities operating ammonia refrigeration systems are governed by a multi-layered regulatory environment in the United States:

• OSHA Process Safety Management (PSM) 29 CFR 1910.119
• EPA Risk Management Program (RMP)
• EPA Clean Air Act
• General Duty Clause (GDC)
• Emergency Planning & Community Right-to-Know Act (EPCRA)
• CISA Chemical Facility Anti-Terrorism Standards (CFATS)

Industry Best Practices Guidelines

Compliance programs under OSHA PSM and EPA RMP heavily rely on Recognized and Generally Accepted Good Engineering Practices (RAGAGEP), primarily established by IIAR and ANSI/ASHRAE:

• ANSI/IIAR 2: Standard for Safe Design of Closed-Circuit Ammonia Refrigeration Systems
• ANSI/IIAR 6: Standard for Inspection, Testing, and Maintenance (ITM) of Low-Temperature Closed-Circuit Ammonia Refrigeration Systems
• ANSI/IIAR 9: Standard for Minimum System Safety Requirements for Existing Closed-Circuit Ammonia Refrigeration Systems
• IIAR Bulletin No. 114: Guidelines for Identification of Ammonia Refrigeration Piping and System
• ANSI/ASHRAE Standard 15: Safety Standard for Refrigeration Systems

Transform Your Risk Management

ioMosaic understands the safety and risk processes that are required or followed around the world, and deliver practical, locally compliant solutions to our clients' safety and risk concerns. If you have questions about ammonia refrigeration safety, we'd love to hear from you. Call us today at 1.844.ioMosaic or send us a note.