GB/T 7778-2017[Including 2019XG1, 2020XG2] Number designation and safety classification of refrigerants (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard replaces GB/T 7778-2008 "Refrigerant Numbering Method and Safety Classification". This standard is in line with GB/T 7778-2008

The changes in the main technical content are as follows.

--- Increased the amount of refrigerant;

--- Increased propylene and ether based refrigerant numbering methods;

--- Revised the numbering method for other organic and inorganic compounds;

--- Revised the classification of toxicity, from A, B, C to A, B;

--- Modified the flammability classification, adding 2L weak flammable class;

--- Increased the method of determining the refrigerant concentration limit RCL;

--- Table 5 added some refrigerant, and increased LFL, ATEL, RCL column;

--- Add a "A.3 propane isomer" and "A.4 stereoisomer example" in Appendix A;

--- Deleted the original standard Appendix B old and new standard safety classification comparison table;

--- Added Appendix B flammability test and fractionation analysis;

--- Added Appendix C to test methods for measuring the burning rate of combustible gases;

--- Added RCL and ATEL calculations for Appendix D mixed refrigerants;

--- Added Appendix E to determine the safety classification and RCL values;

--- Added Appendix F application notes.

This standard uses the redrafting method to modify the use of ISO 817.2014 "Refrigerant Naming and Safety Classification".

The technical differences between this standard and ISO 817.2014 and their reasons are as follows.

---About the normative reference documents, this standard has made technical adjustments to adapt to China's technical conditions, specific adjustments

To. replace ASTME681 with GB/T 21844;

--- Regarding the definition of "occupational exposure limit value", the indicator in ISO 817 is based on relevant national regulations. This standard is for China

The national conditions have increased the regulations that can be referred to in our country (see Note to 3.1.28);

--- Delete the upper corner note b in Table 6, and adjust the original upper corner notes c, d to b, c;

--- Appendix B refers to the reference to Figure B.1 in ANSI/ASHRAE34-2013, which is directly included in this standard after this revision.

Medium (see Appendix B, B.1);

--- The nature of Appendix F was changed from a normative appendix to an informative appendix. Because Appendix F involves applying for refrigerant from a foreign institution.

Numbering.

This standard was proposed by the China Machinery Industry Federation.

This standard is under the jurisdiction of the National Refrigeration and Air Conditioning Equipment Standardization Technical Committee (SAC/TC238).

This standard is drafted by. Hefei General Mechanical and Electrical Products Testing Institute Co., Ltd., Ningbo Bolang Thermal Energy Technology Co., Ltd., Hefei General

Mechanical Research Institute, Hefei General Environmental Control Technology Co., Ltd.

1 Scope

This standard specifies the method for the numbering of refrigerants, the method for safely classifying refrigerants based on toxicity and flammability data, and

A method of determining the refrigerant concentration limit.

This standard applies to refrigerants used in refrigeration and air conditioning equipment and installations.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 21844 Standard Test Method for Flammability Concentration Limits of Compounds (Vapours and Gases)

ANSI/ASHRAE34 Renaming and Safety Classification of Refrigerants (Designationsafetyclassificationofrefriger-

Ants)

3 Terms and definitions, abbreviations and symbols