1、Designation: C919 18Standard Practice forUse of Sealants in Acoustical Applications1This standard is issued under the fixed designation C919; 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 pa
2、rentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice provides information for the use of seal-ants to reduce sound transmission characteristics of interiorwalls, ceilings, and floors by
3、proper application of sealants tojoints, voids, and penetrations normally found in buildingconstruction, which are commonly referred to as “flankingpaths.”1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of
4、this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.3 The committee with jurisdiction over this standard is notaware of any comparable standards published by other orga-nizations.1.4 This intern
5、ational 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) Co
6、mmittee.2. Referenced Documents2.1 ASTM Standards:2C634 Terminology Relating to Building and EnvironmentalAcousticsC717 Terminology of Building Seals and SealantsC834 Specification for Latex SealantsC920 Specification for Elastomeric Joint SealantsC1193 Guide for Use of Joint SealantsC1520 Guide for
7、 Paintability of Latex SealantsC1620 Specification for Aerosol Polyurethane and AerosolLatex Foam SealantsC1642 Practice for Determining Air Leakage Rates of Aero-sol Foam Sealants and Other Construction Joint Fill andInsulation MaterialsE90 Test Method for Laboratory Measurement of AirborneSound Tr
8、ansmission Loss of Building Partitions andElementsE336 Test Method for Measurement of Airborne SoundAttenuation between Rooms in BuildingsE413 Classification for Rating Sound Insulation2.2 HUD Standard:3HUD Minimum Property Standards for Housing, Section4910.12.3 IBC Standard:4International Building
9、 Code (IBC), Section 12063. Terminology3.1 DefinitionsFor definitions of terms used in this rec-ommended practice, see Terminologies C717 and C634.4. Significance and Use4.1 Walls, ceilings, and floors in building construction,especially those that are of lightweight construction, and thatare design
10、ed to reduce or limit sound transmission, can haveundesirable sound transmission characteristics if care is nottaken to seal joints, voids, and penetrations that typically occur.Unsealed joints, voids, and penetrations will substantiallyincrease the sound transmission characteristics of these typeso
11、f construction. By sealing them the transmission of sound canbe substantially diminished by eliminating “flanking paths.”5. Sound Transmission Requirements5.1 The construction industry has adopted Sound Transmis-sion Class (STC) units, as defined in Terminology C634, to ratethe sound transmission pr
12、operties of walls, ceilings, and floors.The STC is determined in accordance with Classification E413.The test data are obtained in accordance with Test MethodsE90 and E336.5.2 Various building and other governmental adopted codesinclude requirements for sound transmission.1This practice is under the
13、 jurisdiction of ASTM Committee C24 on BuildingSeals and Sealants and is the direct responsibility of Subcommittee C24.10 onSpecifications, Guides and Practices.Current edition approved July 1, 2018. Published August 2018. Originallyapproved in 1979. Last previous edition approved in 2012 as C919 12
14、(2017). DOI:10.1520/C0919-18.2For 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 Superintendent o
15、f Documents, U.S. Government PrintingOffice, Washington, DC 20402.4Available from International Code Council (ICC), http:/www.iccsafe.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in acco
16、rdance 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 Organization Technical Barriers to Trade (TBT) Committee.15.2.1 For example, the Internat
17、ional Building Code (IBC),Section 1206.2, has requirements for the amount of sound thatis allowed to be transmitted through common interior walls,partitions, and floor and ceiling assemblies between adjacentdwelling units or between dwelling units and adjacent publicareas of a building; such as hall
18、s, corridors, stairs, or serviceareas. This Section also includes requirements for penetrationsor openings in these assemblies, including piping and electricaldevices, to be sealed, lined, insulated, or otherwise treated tomaintain the required ratings.5.2.2 Additionally, the department of Housing a
19、nd UrbanDevelopment (HUD) has the following standard for STClimitations for various housing units: HUD Minimum PropertyStandards for Housing, Section 4910.1.6. Why Seal Openings?6.1 The sound transmission of a wall, ceiling, or floor, nomatter how well built, can be substantially defeated by thepres
20、ence of unsealed joints, voids, and penetrations. Fig. 1illustrates examples of how sound travels through unsealedjoints, voids, and penetrations in walls and how sealing themwith liquid-applied sealants or precured sealants will minimizesound transmission.6.2 The effect of unsealed joints, voids, a
21、nd penetrations onthe STC rating of partition walls is illustrated in Fig. 2. For thesample wall example, with an STC rating of 40 that hasopenings that total 9 cm2(1.4 in.2) will have its STC reducedto 36 a 10 % difference. However, that small difference resultsin a change to the apparent loudness
22、of sound transmission tothat which is twice as loud.7. Positioning of Sealants7.1 Fig. 3 illustrates placement of liquid-applied sealants toimprove the STC rating from a value of 29 to a value of 53.Note that two properly placed sealants are sufficient andsealing beyond that is unnecessary.8. Applic
23、ation of Sealants8.1 Fig. 4 illustrates typical liquid-applied sealant applica-tions. Additional sealant application information can be ob-tained from Guide C1193 and manufacturers literature forspecific products and applications.9. Types of Sealants9.1 Precured SealantsPrecured sealants include a w
24、idevariety of gaskets and tapes, and foamed shapes that haveconstant dimensions. These materials are effective sound sealswhen the tolerances for joint, void, or penetration opening canbe accurately predicted and installed within those tolerances. Avarying opening width along its length, which excee
25、ds thosetolerances, will cause the gasket, tape or foamed shape to havedifficulty in maintaining a proper seal at all points with theconstant compression that is necessary to effect a seal. Pre-cured sealants in the form of pads have proved to be effectivefor sealing electric, telephone, television
26、and other types ofjack and back boxes.9.2 Non-Sag SealantsThese liquid-applied sealants canconform to the wide range of sizes encountered in joints, voids,and penetrations especially those that have tolerances exceed-ing those applicable for precured sealants. The following typesare available:9.2.1
27、Nondrying, Nonhardening, Nonskinning SealantsThese types of sealants have proven to be effective in reducingsound transmission. By remaining flexible as well as perma-nently adhesive, they can maintain an effective seal. Thesetypes of sealants, for acoustical applications, normally arenonbleeding an
28、d will not stain walls. The nonskinning mate-rials should be used only in concealed areas. If however, theyare exposed to view they are not paintable and may stainadjacent paint and other surfaces or pick up dirt.FIG. 1 Examples of Achieving an Effective Sound Barrier andMaintaining the Designed STC
29、 Value of Partition SystemsC919 1829.2.2 Skinning SealantsLiquid-applied sealants that curein-place, develop a surface skin, retain flexibility, and maintainadhesion can be effective in reducing sound transmission.These sealants are preferred in exposed applications andcertain types can readily acce
30、pt paint and other finishes. Thefollowing types are available:9.2.2.1 Latex-Based SealantsLatex-based sealants that re-tain flexibility and maintain adhesion can be effective inreducing sound transmission. Specification C834 referencesthese sealant types. Guide C1520 refers to their paintabilitychar
31、acteristics and requirements. These sealants are primarilyused for joints, voids, or penetrations that are static and do notexperience movement.9.2.2.2 Aerosol Foam SealantsPolyurethane and latexbased formulations are available for the sealing of irregularjoints, voids, and penetrations to limit sou
32、nd transmission.Specification C1620 references these sealant types. Only thosefoams that have very little or no leakage after installation asdescribed by Test Method C1642, as referenced in C1620should be used. These sealants are primarily used for joints,voids, or penetrations that are static.9.2.2
33、.3 Elastomeric SealantsWhile normally used forsealing joints on the exterior of buildings, they can beeffectively used for interior sound reduction especially forjoints that will be subject to movement. Specification C920references these sealant types, which can include latex,polyurethane, polysulfi
34、de, polyether, and silicone based formu-lations.AC920 Type S or M, Grade NS, Use NT sealant shouldbe used for these applications. C920 sealants are available inthe following movement classes 1212, 25, 35, 50, and 100/50,which represent sealant movement capability. For example,Class 25 indicates 625
35、% movement capability. For example,a sealant in a joint, void, or penetration, that will experiencemovement, and that is14 in. wide has the ability to compressto316 in. or extend to516 in. without failure if properlyinstalled.10. Paintability of Exposed Sealants10.1 Sealants are usually painted if t
36、hey are exposed on theinterior of buildings. Because of the wide variety of types andbrands of interior paint and the equally wide variety of typesand brands of sealants both the paint and sealant manufacturersshould be consulted relative to paintability of a particularcombination of products. On-si
37、te paintability and stain tests arerecommended once paint and sealant product recommenda-tions have been made. Paintability of latex-based sealants isdescribed by Guide C1520. In general, silicone-based sealantswill not provide an acceptable surface for paint application;however, they can be used by
38、 being of a color compatible withadjacent surfaces.10.2 Paint applied before a sealant has cured may crackduring the curing of the sealant. It should also be realized thatstructural or other building movements that affect the sealantmay cause paint to crack or delaminate from the sealantsurface. A r
39、easonable sealant cure time should occur beforepainting. Sealant and paint manufacturers should be consultedregarding a recommended cure time prior to painting.11. Keywords11.1 acoustical; sealants; sound transmissionFIG. 2 Effect of Unsealed Hole Openings on STC-Rated TestWall,3.8by2.4m(12ft6in.by8
40、ft)C919 183Edge DetailSTCValueCommentsunsealed 29 the open-edge track gave the STC value of29 through direct leakagesingle sealant at the perimeter of one baselayer49 this bead closed void but did not seal leak-age around the joint between the wallboardand tracktwo sealants, one for each base layer
41、of gyp-sum board53 the beads closed void and sealed leakagearound trackfour sealants, one for each base and facelayer of gypsum board53 the void is closed; no leaks around track andwallboardNOTE 1The test partitions consisted of metal studs, 610 mm (24 in.) on center, with double layers of 13-mm (0.
42、5in.) wallboard screw-attachedto each side. Sound attenuation blanket, 38 mm (1.5 in.), was placed in the void. The partition panels were erected, shimmed out 3 mm (0.125 in.) atthe periphery: top, bottom, and edges.NOTE 1Data were obtained from the United States Gypsum Co. Round Lake Acoustical Res
43、earch Facilities from a study conducted in accordancewith Test Method E336.FIG. 3 Performance of a Partition System Sealed with Single or Multiple BeadsC919 184ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this stan
44、dard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be revie
45、wed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsibl
46、e technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Con
47、shohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 4 Typical Sealant ApplicationC919 185
