Safety is paramount when working with ammonia refrigerants. Why? If something does go wrong in such a situation, it can have grave consequences.

Ammonia is a health risk because of its corrosiveness to skin, eyes, and lungs. In fact, exposure to 300 ppm creates an imminent danger to life and health. It is important to remember that the safety of technicians and engineers who work with ammonia is as important as in any other working conditions.

These are some real-life examples of what can go wrong:

• In September 2001, an ammonia/ammonium nitrate explosion at a fertilizer plant in Toulouse, France, killed 30 and injured more than 2,000 workers and nearby residents. According to the government investigation, as horrific as the accident was, it could have been much worse if intervening buildings had not broken the force of the explosion, preventing the potential detonation of 20 more railroad tank cars full of anhydrous ammonia.

• A study published by the State of New York Department of Health documented 107 serious ammonia spills that occurred in New York state between 1993 through 1998. Sixty-one people were seriously injured, and one person killed in the reported accidents. Forty-four percent of the injured persons were employees, 41 percent were members of the general public, and 15 percent were emergency responders. Many of the releases occurred in food/beverage processing (29 percent) or at chemical/metal/equipment manufacturing facilities (27 percent). Most of the accidents (101) occurred at fixed facilities; the other six releases were during transportation. Equipment failure caused 58 percent of the releases. Many of the releases involved piping (44 percent). More than 1,889 people were evacuated following these 107 ammonia releases.

Sound the Alarm

One refrigeration contractor, James Taylor of Taylor Refrigeration & HVAC of Las Vegas, said that there are at least two important safety measures required and “much needed for ammonia systems.”

“The first is alarms,” he said. “There needs to be multiple sensors in every area of the machine room, in ceilings where pipes may run, and the evaporator sections. This is very important. I would strongly recommend having sensor alarms in various areas and have them tested and inspected every 90-120 days for proper operations.

“Ammonia is used in many fields of industry. We know all about it because of our work with a dairy production plant. I know it could be very dangerous for a technician or engineer working on systems that use ammonia refrigerant. My recommendations would be to require multiple sensory alarm systems that are globally linked to the building’s alarm system and warn people of a leak.

“My other suggestion would be to have and ensure there is an air evacuation system (exhaust hood system) tied into the alarm panel that automatically comes on as soon as it’s tripped, so as to exchange the air immediately for the safety of the technician, who can then get out of the machine room, and have it tested, recorded, and dated, just like any other public use machinery equipment.

“Knowledge of ammonia systems can be learned, but the safety of ammonia’s use must be very seriously understood.”

Ammonia Training

If you or your employees are interested in ammonia safety training, the International Institute of Ammonia Refrigeration (IIAR) is hosting the 2012 Industrial Refrigeration Conference from March 18-21 in Milwaukee.

According to IIAR, the conference will feature more than 100 industrial refrigeration product and service providers, a technical program including more than 20 presentations, and workshops and panel discussions. In particular, this year the emphasis will be on the industrial refrigeration industry’s end users and features a special Ammonia Safety Training Day event. Technical papers deal with issues ranging from facility design to inspection and test procedures.

For more information or to register for the conference, visit

Publication date: 01/30/2012