ASTM_D_7327_-_12.pdf

Designation:D732712Standard Specification forHFC Blend B(CH2FCF3,CHF2CF3,and CO2)1This standard is issued under the fixed designation D7327;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers requirements for HFC Blend Bas a fire-fighting medium.1.2 This specification does not address the fire-fightingequipment or hardware that employs HFC Blend B or theconditions of employing such equipment(for example,handhelds,fixed installations,etc.).1.3 This specification does not address the storage ortransportation of HFC Blend B.Storage,handling,and trans-portation issues are addressed in Practice D7326.1.4 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.Specific caution-ary statements are given in Section 4.2.Referenced Documents2.1 ASTM Standards:2D7326 Practice for Handling,Transportation,and Storage ofHFC Blend B(CH2FCF3,CHF2CF3,and CO2)D6806 Practice for Analysis of Halogenated Organic Sol-vents and Their Admixtures by Gas Chromatography2.2 ISO Standards:3ISO 3427 Gaseous Halogenated Hydrocarbons(LiquefiedGases)Taking of a Sample2.3 ASHRAE Standard:4ASHRAE 34 Designation and Safety Classification of Re-frigerants2.4 U.S.Government Standards:5CFR Title 49,Part 172,Subpart D,U.S.Department ofTransportation(DOT),Marking Requirements of Packag-ing for TransportationCFR Title 49,Part 172.101 Tables of Hazardous Materialsand Special Provisions2.5 AHRI Standards:62008 Appendix C for Analytical Procedures for AHRI Stan-dard 700-20063.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 HFChydrofluorocarbon;a chemical compound inwhich the compound molecule is comprised exclusively ofhydrogen,chlorine,fluorine and carbon atoms.3.1.2 HFC Blend Btertiary blend comprised of HFC-134a(1,1,1,2-tetrafluoroethane),HFC-125(pentafluoroethane),andcarbon dioxide(CO2);a compound used to inert,extinguish,orsuppress a fire or explosion hazard.3.1.2.1 DiscussionThe terminology system for fluorine-containing compounds(described in detail in ASHRAE Stan-dard 34)provides a convenient means to reference the structureof individual compounds.By definition,the first digit of thenumbering system represents one less than the number ofcarbon atoms in the compound molecule;the second digit,onemore than the number of hydrogen atoms in the compoundmolecule;and the third digit,the number of fluorine atoms inthe compound molecule.Unaccounted for valence require-ments are assumed to be chlorine atoms.For example,thedesignation HFC-123 indicates two carbon atoms(1+1),twohydrogen atoms(3-1),and four fluorine atoms(4).The“a”designation at the end of the naming convention relates to the1This specification is under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and is the directresponsibility of Subcommittee D26.09 on Fire Extinguishing Agents.Current edition approved Sept.1,2012.Published October 2012.Originallyapproved in 2007.Last previous edition approved in 2007 as D7327-07.DOI:10.1520/D7327-12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute,11 W.42nd St.,13thFloor,New York,NY 10036.4Available from American Society of Heating,Refrigerating,and Air-Conditioning Engineers,Inc.(ASHRAE),1791 Tullie Circle,NE,Atlanta,GA30329.5Available from Superintendent of Documents,U.S.Government PrintingOffice,Washington,DC 20036.6Available from Air-Conditioning,Heating,and Refrigeration Institute,2111Wilson Blvd.,Suite 500,Arlington,VA 22201.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 symmetry of the molecule.Example:CH2FCF3=HFC-134a4.Material Requirements4.1 Type I Mixtures of HFC Blend B and Nitrogen:4.1.1 The nitrogen(N2)partial pressure shall be such thatthe safe working pressure of the receiving vessel is notexceeded.To prevent excessive pressure,the fill density ofHFC Blend B within a container should not exceed that neededto achieve complete filling of the container at the maximumenvisaged storage temperature.For example,for the U.S.DOT4BA500 cylinder,the nitrogen partial pressure shall