The original SAE J2727 "Emission Chart" provided a rating system for comparing mobile A/C systems and was not intended to define mobile A/C system refrigerant emission. It had been developed from industry experience of expected system refrigerant emission based upon currently available technologies. The "System Emissions Chart" now contained in this revision is intended to serve as a means of estimating the annual refrigerant emissions rate (grams per year) from new production A/C systems equipped with specified component technologies. It provides emission values for various component technologies that are currently available, and can be expanded as new technologies are commercialized. This document provides the information to develop an Excel file template "System Emissions Chart" for system emission analysis. The chart includes automotive compressor technologies for conventional mobile air conditioning systems as well as those using semi-hermetic compressors. This standard can be considered a companion document to SAE J2763 Test Procedure for Determining Refrigerant Emissions from Mobile Air Conditioning Systems. SAE J2727 estimates system emissions, taking into account production assembly variation. SAE J2763 may be used to quantify emissions from properly assembled systems.
Industry standards did not exist for measuring, or estimating, refrigerant emissions from mobile air conditioning systems when the original version of SAE J2727 was created in 2005. This revision is based on laboratory measurements and field correlations and supersedes the original, which provided a relative system emission rating based solely on component technology used in the system combined with expert input regarding relative emission rates of components.