1、Designation:D430821An American National StandardStandard Test Method forElectrical Conductivity of Liquid Hydrocarbons by PrecisionMeter1This standard is issued under the fixed designation D4308;the number immediately following the designation indicates the year oforiginal adoption or,in the case of
2、 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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This test metho
3、d covers and applies to the determinationof the“rest”electrical conductivity of aviation fuels and othersimilar low-conductivity hydrocarbon liquids in the range from1 pS m to 2000 pSm(see 3.1.2).This test method can be usedin the laboratory or in the field.1.2 The values stated in SI units are to b
4、e regarded asstandard.No other units of measurement are included in thisstandard.1.3 WARNINGMercury has been designated by manyregulatory agencies as a hazardous substance that can causeserious medical issues.Mercury,or its vapor,has been dem-onstrated to be hazardous to health and corrosive to mate
5、rials.Use Caution when handling mercury and mercury-containingproducts.See the applicable product Safety Data Sheet(SDS)for additional information.The potential exists that sellingmercury or mercury-containing products,or both,is prohibitedby local or national law.Users must determine legality of sa
6、lesin their location.1.4 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 limitati
7、ons prior to use.For specific warning statements,see 8.3 and Annex A1.1.5 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-m
8、endations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D150 Test Methods for AC Loss Characteristics and Permit-tivity(Dielectric Constant)of Solid Electrical InsulationD2624 Test Methods for Electrical Conductivity of Avia
9、tionand Distillate FuelsD4306 Practice for Aviation Fuel Sample Containers forTests Affected by Trace ContaminationE1 Specification for ASTM Liquid-in-Glass Thermometers3.Terminology3.1 Definitions:3.1.1 picosiemens per metre,nthe unit of electrical con-ductivity is also called a conductivity unit(C
10、U).A siemen isthe SI definition of reciprocal ohm sometimes called mho.1 pS/m 5 1 31021221m215 1 cu5 1 picomho/m(1)3.1.2 rest conductivity,nthe reciprocal of the resistance ofuncharged fuel in the absence of ionic depletion or polariza-tion.It is the electrical conductivity at the initial instant of
11、current measurement after a dc voltage is impressed betweenelectrodes.4.Summary of Test Method4.1 A sample of liquid hydrocarbon is introduced into aclean conductivity cell which is connected in series to a batteryvoltage source and a sensitive dc ammeter.The conductivity,automatically calculated fr
12、om the observed peak current read-ing dc voltage and cell constant using Ohms law,appears as adigital value in either a manual or automatic mode of meteroperation.5.Significance and Use5.1 The generation and dissipation of electrostatic charge infuel due to handling depend largely on the ionic speci
13、es present1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.J0.04 on Additives and Electrical Properties.Current edition approved Jan.1,2021.Published March 2021.Originallyapproved in
14、 1983.Last previous edition approved in 2013 as D4308 13.DOI:10.1520/D4308-21.2For 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 A
15、STM website.*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 standardizati
16、on established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1which may be characterized by the rest or equilibrium electri-cal conductivity.The time for static charge to dissipate isinversely related to conductivity.This test method can supple-ment Test Method D2624 which is limited to fuels containingstatic dissipator additive.NOTE1For low-conductivity fluid