The use of ammonia as a refrigerant has been around for approximately 160 years, dating back to its first use in France in the 1850s. It first appeared in the United States in the 1860s when it was used for artificial ice production. Its popularity as a refrigerant increased during its usage in block ice, food processing and warehousing, and chemical production facilities. Eventually ammonia refrigerant was used in ice arenas and air conditioning units. Today, ammonia refrigerant is used in air conditioning for the International Space Station and Biosphere II, a man-made controllable environment. Its latest uses are a testament to the growing popularity of ammonia refrigerants.

This increased usage can be attributed to a number of reasons. A. Bruce Badger, president of the International Institute of Ammonia Refrigeration (IIAR), talked about some of those reasons. “Ammonia is a natural refrigerant that is non-ozone depleting and does not contribute to global warming, which makes it an ideal refrigerant for use in large industrial applications,” he said. “These applications include large-scale food and beverage processing, cold storage warehouses, district cooling, the pharmaceutical industry, and recreation facilities (ice rinks).”

Anhydrous (without water) ammonia is widely used in all industrial applications because of its environmental advantages, high energy efficiency, and rapid recovery of investment, said IIAR.

Ammonia refrigerant use in food processing facilities is vital, said IIAR. “Most of the food consumed in North America is stored or processed in facilities that use ammonia as a refrigerant,” Badger said. “That includes meat; dairy; fish; frozen food; fresh fruit and vegetables; dairy products such as milk, cheese, and ice cream; and beverages such as beer, wine, soft drinks, and freeze-dried coffee.”

“The risks associated with using ammonia as a refrigerant are no greater than the risks associated with other common refrigerants,” Badger said. “The primary difference is that ammonia has a pungent odor that serves as a very effective safety alarm.”

Handling ammonia refrigerants should be left to qualified people, said Badger. “Operating or performing maintenance on any refrigeration systems — large or small — should only be performed by a trained individual,” he added. “There are important differences associated with working on an ammonia refrigeration system compared with other refrigerants. For example, while copper tubing is commonly used in smaller HVAC systems, it should never be used in an ammonia refrigeration system.

“While there is no formal apprentice program or requirement for certification, there is an ANSI-approved certification program for operators. Historically, industrial refrigeration operators learned their skills — and still do — through on-the-job training or information sharing and periodic training programs offered by trade associations such as IIAR and RETA [Refrigerating Engineers and Technicians Association]. During the past 10 years, a growing number of technical schools across the U.S., both private and public, have begun to offer weeklong operator training at various skill levels. In addition, more community college HVAC programs are adding an industrial refrigeration course.”

Badger said that the usage of ammonia refrigerants is common across the United States. “There is nothing geographically unique about the use of ammonia as an industrial refrigerant,” he said. “Facilities that use ammonia can be found in every region of the country,” he noted. “It is estimated that there are more than 8,000 industrial refrigeration systems that use ammonia as a refrigerant in operation in the U.S.”

Ammonia Conference

IIAR is holding its annual conference and exhibition on March 18-12, 2012 in Milwaukee. The IIAR describes this event as “a highly qualified audience of industrial refrigeration decision-makers who represent hundreds of contracting firms and thousands of end user facilities from the United States, Canada, Mexico, Latin America, Europe, Asia, and Australia. Your customers (and your competition) will be there. You should be too!”

For more information on the IIAR event or on ammonia refrigerants, visit

Publication date: 11/28/2011