RT null T1 Update on New Refrigerants Designations and Safety Classifications - UNEP ASHRAE Factsheet 1 A1 United Nations Environment Programme, A1 OzonAction, A1 American Society of Heating, Refrigerating and Air-Conditioning Engineers K1 ozone K1 ozone-depleting substance K1 ozone layer K1 refrigeration YR 2015 FD 2015 LK https://wedocs.unep.org/handle/20.500.11822/26711 UL https://wedocs.unep.org/handle/20.500.11822/26711 NO This document is a fact sheet that updates readers on refrigerant standards from the American Society of Heating, Refrigerating and Air-Conditioning Engineers and introduces refrigerants recently assigned “R” numbers and placed on the international market. It explains how Standard 34 assigns refrigerant numbers for pure substances and blends and describes safety classifications that combine toxicity classes with flammability classes, including the newer subclass for slowly burning, mildly flammable refrigerants. It also summarizes safety issues addressed in Standard 15 for refrigeration systems. The document provides a table of refrigerant designations introduced after 2010 with safety groups, global warming potential values, and boiling-point information, and notes cooperation with the United Nations Environment Programme. DS UN Environment Document Repository RD Sep 22, 2026