Safety Management of Ammonia Refrigerant Systems
Ammonia refrigeration is along standing form of refrigeration that is still commonly used today to keep various products cold. This method of refrigeration is popular due to its reliability, efficiency, safety, and proven usefulness. Because of these benefits, ammonia refrigeration is utilized by a wide range of industrial facilities, such as:
- Meat, poultry, or fish processing plants
- Cold storage warehouses and ice plants
- Dairy and ice cream plants
- Fruit/vegetable juice and soft drink processing facilities
- Wineries and breweries
- Chemical manufacturing facilities
Although ammonia refrigeration is safe when properly used, accidental ammonia leaks or releases can pose serious injuries and even death to employees, emergency response personnel, and people in the surrounding environment. To avoid this, there are many requirements and standards that facilities must meet to ensure safe conditions.
Hazards of Ammonia
An accidental release of ammonia sometimes produces a dense, visible white cloud that travels close to the ground. However, if there is no visible cloud, the odor itself will prompt the necessity of evacuation, either inside or outside.
The odor becomes evident when 5 to 50 parts per million (ppm) of ammonia is released. At this level, it is toxic, causing symptoms like headaches, loss of smell, nausea, and vomiting. Emissions of above 50 ppm produce irritation of the nose, mouth, and throat, resulting in coughing and wheezing. Exposure to 300 ppm to 500 ppm of ammonia can be fatal, causing extreme shortness of breath and even fluid buildup in the lungs. Other side effects include frostbite and chemical burns to the skin, eyes, and lungs.
Another major hazard of ammonia is its flammability. If there has been a leak of ammonia, just an electric spark from a switch could produce an explosion or fire.
Ammonia Safety Requirements
Because of ammonia’s many hazards, various associations have outlined standards of ammonia refrigeration safety. These include:
IIAR is the world’s leading advocate for the safe, reliable and efficient use of ammonia and other natural refrigerants. IIAR members share their collective knowledge and experience to produce consensus documents that address various aspects of the natural and industrial refrigeration industry. IIAR has broad industry representation including manufacturers, design engineers, contractors, end users, academics, scientists, and trainers. IIAR sets the standard for providing advocacy, education and the most up-to-date technical information to the ammonia and natural refrigeration community.
If your ammonia refrigeration system has 10,000 pounds (2,000 gallons) or more of ammonia, it is subject to the requirements of OSHA Process Safety Management (PSM) Standard [29 CFR 1910.119].
The EPA has published documents that outline the responsibilities of ammonia refrigeration operators when it comes to preventing accidents. According to the Clean Air Act, owners and operators are required to develop Risk Management Programs that are designed to prevent or reduce the consequences of accidental ammonia releases. Additionally, plants or facilities that store large amounts of ammonia (more than 500 pounds) must report and coordinate with their Local Planning Committee as well as their State Emergency Commission.
Department of Homeland Security (DHS)
The DHS requires high-risk chemical facilities to develop site security plans, complete security vulnerability assessments, and implement the necessary protective measures to meet risk-based performance standards defined by the DHS.
Ammonia Safety and Accident Prevention
According to the EPA, 96% of ammonia-related accidents are preventable through better communication, improved procedures, and enhanced operator training. To make sure that accidents don’t happen, it’s important to implement the following:
Worker and System Protection
Training and awareness of the hazards associated with anhydrous ammonia will lead to greater care to prevent ammonia releases. Developing operating procedures that follow RAGAGEP, such as the ANSI/IIAR standard 7-19, will help keep personnel safe. Other steps you can take to protect your workers and systems include:
- Oil removal
- Protect equipment, tanks, and piping
- Install, maintain, and inspect ammonia detector systems
- Install emergency ventilation switches
- Configure remote operation of solenoid valve on king valve line
- Install check valves in the ammonia charging line
- Install dual pressure relief valves
- Color coding, labeling, and signage
System Operations and Maintenance
You should implement a mechanical integrity plan for each component of your ammonia refrigeration system. To ensure compliance with 40 CFR 68.73, these procedures must be written and regularly performed to ensure the ongoing integrity of process equipment. ANSI/IIAR standard 6-19 spells out minimum requirement, some of the common system operation and maintenance procedures include:
- Monitor refrigeration system operating parameters
- Maintain good housekeeping practices
- Maintain piping and instrumentation diagrams
- Track ammonia purchases and distribution of ammonia in your system
- Conduct a periodic process hazard analysis
In addition to preventive maintenance measures, scheduled inspections should be performed to prevent unnecessary accidents from equipment failure. Systems inspections include:
- Visual testing
- Leak testing
- Vibration testing
- Thermal imaging
Operators of ammonia systems should be fully trained and qualified. Personnel who work within these areas should be provided with awareness training, such as safety and evacuation procedures, should a leak occur.
Ammonia theft and vandalism of ammonia storage and refrigeration systems have resulted in the accidental release of ammonia. Installing site security safeguards is another form of prevention.
Ammonia Safety at Kuhlman, Inc.
Ammonia refrigeration systems offer a safe and reliable way to keep products cold as long as you adhere to ANSI/IIAR standard 9-20 RAGAGEP. At Kuhlman, Inc., we can deliver refrigeration systems that meet the needs of various industries. To discuss your specific refrigeration requirements with one of our expert team members, contact us or request a quote today.