Refrigerant Climate Data
 James M. Calm, “Refrigerant Data Summary,” Engineered Systems Magazine November 2001.
||Atmospheric Lifetime in Years
||Ozone Depletion Potential
||Global Warming Potential
CFCs generally have high Ozone Depletion Potential and Global Warming Potential with long Atmospheric Lifetimes. CFCs are therefore not allowed by these guidelines and prohibited by MN state law. Halons have a higher Ozone Depletion Potential though a lower Global Warming Potential but a much longer Atmospheric Lifetime. Halons should be avoided if possible. HCFCs such as R-123, which other guides put in the same class as Halons, can have an Ozone Depletion Potential, a Global Warming Potential and an Atmospheric Lifetime two orders of magnitude less than CFCs and Halons. HFCs offer near zero Ozone Depletion Potential, but some have high Global Warming Potential. For example, R-134 has an Ozone Depletion Potential of 0.0 but a Global Warming Potential and an Atmospheric Lifetime approximately ten times greater than R-123, an HCFC alternative. Substituting an HFC, which tends to be less energy efficient than an HCFC, may result in the use of more energy, resulting in a further increase in global warming.
Implementation in the Design Process:
In Predesign and early design determine onsite fire suppression requirements. Plan and organize building to minimize the need for the use of Halon fire suppression systems
Using the tables above and other information as may be available at the time of design, identify candidate refrigerants that have a low Global Warming Potential, short Atmospheric Lifetime, and a low Ozone Depletion Potential.
Use one of the weighted evaluation metrics provided to evaluate the refrigerants, and prioritize the list in the order given. Evaluate the economic and community impacts of the prioritized list and adjust priorities pursuant to the analysis.
In construction documents based on this analysis, develop specifications based on adjusted priorities. Verify shop drawings to assure compliance.