ASTM_D_7877_-_14.pdf

Designation:D787714Standard Guide forElectronic Methods for Detecting and Locating Leaks inWaterproof Membranes1This standard is issued under the fixed designation D7877;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 guide describes standard procedures for usingelectrical conductance measurement methods to locate leaks inexposed or covered waterproof membranes.1.2 This guide addresses the need for a general technicaldescription of the current methods and procedures that are usedto test and verify the integrity of waterproof membranes.1.3 This guide is not intended to replace visual,infrared,orother methods of inspection.It is to be used in conjunction withother methods of roof inspection when specified.1.4 This guide recommends that the leak locationequipment,procedures,and survey parameters used are cali-brated to meet established minimum leak detection sensitivity.The leak detection sensitivity calibration should be verified ona regular basis according to the manufacturers recommenda-tions.1.5 Leak location surveys can be used on waterproofingmembranes installed in roofs,plaza decks,pools,waterfeatures,covered reservoirs and other waterproofing applica-tions.1.6 The procedures are applicable for membranes made ofmaterials such as polyethylene,polypropylene,polyvinylchloride,bituminous material,and other electrically insulatingmaterials.1.7 This guide provides a general description of the equip-ment and methods for locating membrane breaches usingelectric conductance.Refer to the manufacturers instructionsfor the proper operation and use of the equipment described inthis guide.1.8 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.2.Referenced Documents2.1 ASTM Standards:2D1079 Terminology Relating to Roofing and WaterproofingD5957 Guide for Flood Testing Horizontal WaterproofingInstallationsD6747 Guide for Selection of Techniques for ElectricalDetection of Leaks in Geomembranes2.2 NFPA Standard:3NFPA 70 National Electric Code3.Terminology3.1 For definitions of terms,see Terminology D1079.3.2 Definitions of Terms Specific to This Standard:3.2.1 breachas defined for this guide,a membrane breachis a defect in the membrane that allows surface water to reachthe substrate below.3.2.2 conductancethe ability of a material to pass elec-trons.The unit of conductance is the Siemens(S),the relation-ship that exists between resistance(R)and conductance(G)isa reciprocal one.In terms of resistance and conductance:R 5 1G ohms,G5 1R Siemens(1)3.2.3 deckthe structural surface to which the roofing orwaterproofing system(including insulation)is applied.3.2.4 electric currentthe flow of electric charge.Theelectric charge that flows is carried by mobile electrons in aconductor measured in amps.3.2.5 electric gradientthe potential difference betweentwo points measured in volts.3.2.6 high voltagefor purposes of this guide,the UnitedStates 2005 National Electrical Code(NEC)defines highvoltage as any voltage over 600 V(article 490.2).3.2.7 leakany unintended opening,perforation,slit,tear,puncture,crack,hole,cut,or similar breaches through an1This guide is under the jurisdiction of ASTM Committee D08 on Roofing andWaterproofing and is the direct responsibility of Subcommittee D08.22 on Water-proofing and Dampproofing Systems.Current edition approved Aug.1,2014.Published August 2014.DOI:10.1520/D7877-14.2For 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 National Fire Protection Association(NFPA),1 BatterymarchPark,Quincy,MA 02169-7471,http:/www.nfpa.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 installed waterproofing membrane which may allow the pas-sage of liquid.Scratches,gouges,or other aberrations that donot completely penetrate the membrane are not considered tobe leaks as the term is used in this guide although they may bedefects requiring attention.3.2.8 leak detection sensitivitythe smallest size liquidwater leak that the leak location equipment and survey meth-odology are capable of detecting under a given set of condi-tions.The leak detection sensitivity specification is usuallystated as the minimum electrical leakage current that can bedetected and is directly related to the area of the smallest liquidwater leak that can be reliably detected.3.2.9 low voltagefor purposes of this