In 2007 the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) revised their standard #34 to include a new Flammability Classification called “2L” Refrigerants. This new class is based on burning velocities and their lower pressure rise when they are ignited. The IFC 2018 Edition has caught up and now includes some specific requirements and exemptions for this class of refrigerants. Basically, these 2L refrigerants can be managed the same way Anhydrous Ammonia is managed when it is used as a refrigerant. You can find these new requirements in Sections 605.13, 605.16 – 605.17. I need to point out that these new requirements ONLY apply to processes where these new refrigerants are being used as a refrigerant in a mechanical refrigeration process.