Ammonia Detection Systems

Author: Marc Risdahl

Ammonia Detection Systems

Anhydrous Ammonia leaks in your facility pose a severe risk to the safety and well-being of all employees. Ammonia exposure can cause respiratory tract issues and in worse cases; death. This is why we at Carlson and Stewart Refrigeration know it’s crucial to have a proper ammonia detection system installed in your facility.

According to the IIAR American National Standard, at least one ammonia detector should be provided in an area with ammonia equipment (generally speaking). The detector should activate an alarm that reports to a monitored location where corrective action can be taken at an indicated concentration of 25 ppm or higher. Audible and visual alarms should be provided in each room, triggering at a level not exceeding 25ppm, in a spot that’s visible from anywhere in the room. Additional audible and visual alarms should be located outside of the room above each entrance to warn others that only authorized personnel and emergency responders are allowed to enter.

If detection of ammonia equals or exceeds 150ppm, emergency ventilation should be activated along with the visual and audible alarms. In occupied areas, outdoor air should be provided at a rate of at least 0.5 cfm/ft^2 of machinery room area or 20 cfm per occupant, whichever is greater.

If the ammonia concentration in the room exceeds the ammonia detectors upper limit or 40,000 ppm, visual and audible alarms should be activated, emergency ventilation should be engaged, and the following equipment in the compressor room should be automatically de-energized:

  1. Refrigerant Compressors.
  2. Refrigerant Pumps.
  3. Normally closed automatic refrigerant valves that are not part of an emergency control system.

Carlson and Stewart Refrigeration has installed a number of ammonia detection systems and can help you install a new system or assess your existing system to see if it meets current IIAR standards.