This is an archived recording of the 2017 online version of the course. Continuing education credits and/or professional development hours are not available.

ASHRAE Standard 34 maintains a list of refrigerants with a standardized system of assigned refrigerant numbers and well defined safety classifications, including toxicity and flammability ratings. This ever growing list of refrigerants currently includes 161 chemicals and chemical blends that have been proposed for use as refrigerants.

There has long been use of flammable and toxic materials as refrigerants, such as propane and ammonia, but their use has been restricted to appropriately design industrial systems, as proscribed in ASHRAE Standard 15 and other safe use guidelines. Presently, concern about global climate change is driving the cooling industry to consider new classes of chemicals to be used as refrigerants. With the new chemicals are new safety classifications for flammability, including "Class 2L".

This short course explains how the changing needs of society are creating requirements for new refrigerants to be developed and used. The course also explains the new safety classifications that are being proposed and some of the ramifications of these new classifications.