ANSI/ASHRAE Standard 34-2001, Designation and Safety Classifications of Refrigerants
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Addendum a (Table 1: Added safety classification 'A1' for R-C318.)
Addendum b (Table 2 and Table B1: Added a designation of R-415A to the blend R-22/152a (82.0/18.0) with tolerances of (±1.0/±1.0) and a safety classification of A2.)
Addendum c (Table 2 and Table B1: Added a designation of R-418A to the blend R-290/22/152a (1.5/96.0/2.5) with tolerances of (±0.5/±1.0/±0.5) and a safety classification of A2.)
Addendum d (Section 3: Further defined the term 'refrigerant' as it applies to ANSI/ASHRAE Standard 34-2001.)
Addendum e (Section 4.4: Further defined the method for designation of refrigerant blends. Provides additional guidance on the specification of blend compositions and composition tolerances.)
Addenda f, g, h (f: Table 2 and Table B1: Added a designation of R-E170 for dimethyl ether and a safety classification of A3; g: Table 2 and Table B1: Added a designation of R-419A to the blend R-125/134a/E170 (77.0/19.0/4.0) with tolerances of (± 1.0/ ±1.0/±1.0) and a safety classification of A2; h: Table 2 and Table B1: Added a designation of R-415B to the blend R-22/152a (25.0/75.0) with tolerances of (± 1.0/ ±1.0) and a safety classification of A2.)
Addendum i (adds a designation of R-420A to the blend R-134a/142b (88.0/12.0))
Addendum j (Revise text in Subsection 6.1.3 and update reference to ASTM E681 in Section 9, References.)
Addendum l (Section 3: Delete without substitution the struck-through text.)
Addendum m (Deletes Table B1 from Appendix B.)