ASTM_D_7959_-_19.pdf

Designation:D795919An American National StandardStandard Test Method forChloride Content Determination of Aviation Turbine Fuelsusing Chloride Test Strip1This standard is issued under the fixed designation D7959;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.Scope*1.1 This test method covers a rapid means of determiningchloride content of aviation turbine fuel.This methodology isapplicable for chloride concentrations between 0 mg L to0.5 mgL.This methodology will not detect chlorine originat-ing from chlorinated organic compounds(that is,covalentbond).1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricants2.2 ASTM Adjuncts:Distillate Fuel Bar Chart33.Summary of Test Method3.1 A 3 L sample of aviation turbine fuel is extracted withpH 7 buffer solution by a magnetic stir plate and stir bar.Thechloride in the aviation turbine fuel sample transfers to thebuffer solution.A portion of the aqueous extract solution isthen removed and analyzed with a chloride test strip.Silverions within the test strip combine with chloride ions in theextract as it is drawn up by capillary action to form a whitecolumn of silver chloride.The chloride concentration of theextract,determined by the height of the column,is then relatedback to the chloride content of the aviation turbine fuel sample.4.Significance and Use4.1 Chloride present in aviation turbine fuel can originatefrom refinery salt drier carryover or possibly from seawatercontamination(for example,product transferred by barge).Elevated chloride levels have caused corrosive and abrasivewear of aircraft fuel control systems leading to engine failure.45.Interferences5.1 Some pH 7 buffer solution can contain trace levels ofchloride compounds and therefore produce a false positivereading on the chloride test strip.Prior to using a new batch ofpH 7 buffer solution,a sample should be confirmed to produceno reading on the chloride test strip.5.2 The test strip5will react with halides other than chloride(for example,bromide,iodide).The concentration of chloridein salt used in refinery salt driers(predominantly NaCl andCaCl2)and in seawater,however,is in great excess comparedto that of other halides.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.J0.05 on Fuel Cleanliness.Current edition approved May 1,2019.Published June 2019.Originallyapproved in 2015.Last previous edition approved in 2016 as D7959 16.DOI:10.1520/D7959-19.2For 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 ASTM International Headquarters.Order Adjunct No.ADJD417601.Original adjunct produced in 1991.4Guidelines for Sodium Chloride Contamination Troubleshooting and Decon-tamination of Airframe and Engine Fuel Systems,International Air TransportAssociation,2nd Ed.,February 1998,pg.1.5The sole source of supply of the apparatus(Chloride QuanTab(trademarked)Test Strips,30 600 mg/L)known to the committee at this time is Hach Company,P.O.Box 389,Loveland,Colorado 80539-0389,http:/.If you areaware of alternative suppliers,please provide this information to ASTM Interna-tional Headquarters.Your comments will receive careful consideration at a meetingof the responsible technical committee,1which you may attend.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organiza