Safety Evaluation of Coolants & Ammonia Management Systems

The use of extensive quantities of refrigerants in industrial refrigeration and air conditioning systems and the corresponding risks to personnel arising from the possibility of a relevant leakage of small or significant quantities of refrigerant gases, dictate the necessity of compliance with the EN 378 series of European standards (EN 378-1,2,3&4) regarding the "Safety and environmental requirements for refrigerating systems and heat pumps".

According to these standards, specific compliance requirements in the regulations satisfaction and design level are provided for:

• The number and size of refrigerant safety relief valves.
• The activation detection mechanism of safety relief valves
• The coolant leakage detection in freezing systems and cold accumulator systems
• The detection of refrigerant gas leaks in cryostats, and coolant pipelines
• The existence of emergency ventilation systems of the cryostat facilities and the existence of similar intermittent operation systems of the refrigeration mechanisms.

Cryostats that need a compliance study with the above-mentioned standards are mainly those that are existing ones and use ammonia for the production of cooling. Ammonia, due to its inorganic nature, even though is considered as more eco-friendly regarding the environmental pollution and Ozone destruction, on the other hand, when compared with other coolant liquids is more dangerous when personnel are exposed to it, due to its high toxicity, and it requires absolute compliance with the standards regarding its use.

Ergonomia, in the framework of the safety evaluation services of ammonia refrigerating systems, can totally undertake the following tasks:

• The Piping and Instrumentation Diagrams (PIDs) of the existing Ammonia refrigeration facilities
• Conduct the dimensioning calculations for the emergency safety valves based on the methods prescribed into the applied standards. Compliance assessment of the existing network with the requirements for secondary relief valves installation together with the corresponding detector which detects and announces the activation of these valves
• Selection and positioning of gas detectors, based on the relative directives and guidelines.
• Evaluation of the existing Cryostat room ventilation systems. In case that the existing network is insufficient, the design of the safety and emergency ventilation network using specialized software tools can be undertaken.
• Evaluation and design of the ventilation system of Ammonia pipelines auxiliary and secondary spaces.
• Design suggestions of emergency escape means and selection of appropriate personal protective equipment for ammonia environments.