Recent Blog Posts

Differences Between IIAR Standards 2 and 9

September 15th, 2020

Earlier this year, IIAR published ANSI/IIAR 9-2020 Standard for Minimum System Safety Requirements for Existing Closed-Circuit Ammonia Refrigeration Systems. While it has long been recognized that new systems must adhere to the requirements of IIAR Standards 2 and 4, facilities with existing systems have often been confused on how they should relate to these standards. […]

Permissible Locations of Ammonia Refrigeration Equipment

May 12th, 2020

ANSI/IIAR 2-2014 Addendum A Chapter 4 Location of Ammonia Refrigeration Machinery, prescribes the acceptable locations for installing ammonia refrigeration equipment. In general, it is expected that equipment will be installed inside a machinery room, but four alternatives are permitted. Exception 1 – Listed Equipment 4.2.1 allows listed equipment containing not more than 6.6 lbs of ammonia […]

Do Machinery Rooms Require a Shunt Trip?

August 6th, 2019

The term “shunt trip” is often used in discussions regarding an ammonia refrigeration machinery room e-stop. Technically speaking, a shunt trip is a device that is designed to trip a circuit breaker remotely. In the context of an ammonia refrigeration system, the shunt trip would be located outside the machinery room so that all power […]

Ventilation System Tests

August 7th, 2018

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 […]

Ammonia Refrigeration and 2018 NFPA 1 (Fire Code)

July 24th, 2018

The National Fire Protection Association (NFPA) recently released their publication of the 2018 NFPA 1 Fire Code and it contains two noteworthy changes from the 2015 version that will impact ammonia refrigeration systems built under the jurisdiction of this code. If your facility is already using IIAR as your primary standard for ammonia refrigeration, these […]