1、Designation:C91908 Designation: C919 12Standard 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 revis
2、ion. 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 practice is a guide provides information for the use of sealants to reduce the sound transmission characteristics ofinterio
3、r walls, ceilings, and floors by proper application of sealants to joints, voids, and penetrations normally found in buildingconstruction, which are commonly referred to as “flanking paths.”1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It
4、is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.3 The committee with jurisdiction over this standard is not aware of any comparable standards published by otherorganizations
5、.2. Referenced Documents2.1 ASTM Standards:2C570Specification for Oil- and Resin-Base Caulking Compound for Building ConstructionC634 Terminology Relating to Building and Environmental AcousticsC717 Terminology of Building Seals and SealantsC834 Specification for Latex SealantsC920 Specification for
6、 Elastomeric Joint SealantsC1193 Guide for Use of Joint SealantsC1520 Guide for Paintability of Latex SealantsC1620 Specification for Aerosol Polyurethane and Aerosol Latex Foam SealantsC1642 Practice for Determining Air Leakage Rates of Aerosol Foam Sealants and Other Construction Joint Fill and In
7、sulationMaterialsE90 Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and ElementsE336 Test Method for Measurement of Airborne Sound Attenuation between Rooms in BuildingsE413 Classification for Rating Sound InsulationE497Practice for Installing Sound
8、-Isolating Lightweight Partitions Classification for Rating Sound Insulation2.2 DHUD Standards:HUD Standard:3HUD Minimum Property Standards for One and Two Family Housing, Section 4900.1HUD Minimum Property Standard for Multi Family Housing, Section 4910.1HUD Minimum Property Standard for Care Type
9、Housing, Section 4920.1HUD Minimum Property Standards for Housing,Section 4910.12.3 IBC Standard:4International Building Code (IBC), Section 12073. Significance and Use3.1Construction utilizing lightweight walls and floors can have undesirable sound transmission characteristics if care is not takent
10、o seal joints and voids that are common to this type of construction. By sealing these penetrations the transmission of sound canbe diminished.1This practice is under the jurisdiction ofASTM Committee C24 on Building Seals and Sealants and is the direct responsibility of Subcommittee C24.10 on Speci
11、fications,Guides and Practices.Current edition approved MayJune 1, 2008.2012. Published June 2008.July 2012. Originally approved in 1979. Last previous edition approved in 20022008 as C919 028.DOI: 10.1520/C0919-08.10.1520/C0919-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org
12、, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402.4Available from Internationa
13、l Code Council (ICC), 500 New Jersey Ave., NW, 6th Floor, Washington, DC 20001, http:/www.iccsafe.org.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technic
14、ally possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box
15、 C700, West Conshohocken, PA 19428-2959, United States.4.Sound Transmission Class4.1The construction industry has adopted Sound Transmission Class (STC) units (defined in Definitions Terminology3.1 DefinitionsFor definitions of terms used in this recommended practice, see Terminologies C717 and C634
16、) to rate thesound barrier properties of walls, ceilings, and floors. The STC is determined in accordance with Classification .4. Significance and Use4.1 Walls, ceilings, and floors in building construction, especially those that are of lightweight construction, and that aredesigned to reduce or lim
17、it sound transmission, can have undesirable sound transmission characteristics if care is not taken to sealjoints, voids, and penetrations that typically occur. Unsealed joints, voids, and penetrations will substantially increase the soundtransmission characteristics of these types of construction.
18、By sealing them the transmission of sound can be substantiallydiminished by eliminating “flanking paths.”5. Sound Transmission Requirements5.1 The construction industry has adopted Sound Transmission Class (STC) units, as defined in Terminology C634, to rate thesound transmission properties of walls
19、, ceilings, and floors. The STC is determined in accordance with Classification E413. Thetest data are obtained in accordance with Test Methods E90 or and E336. Note1For example, The Department of Housing andUrban Development (DHUD) has issued the following three standards dealing with the STC limit
20、ation in various housing units:HUD Minimum Property Standard for One and Two Family Housing, Section 4900.1; HUD Minimum Property Standard for MultiFamily Housing, Section 4910.1; and HUD Minimum Property Standard for Care Type Housing, Section 4920.15.Need to Seal Openings5.1The effect of unsealed
21、openings on the STC of partition walls is shown in5.2 Various building and other governmental adopted codes include requirements for sound transmission.5.2.1 For example, the International Building Code (IBC), Section 1207, has requirements for the amount of sound that isallowed to be transmitted th
22、rough the interior walls, partitions, and floor and ceiling assemblies between adjacent dwelling unitsand between them and public spaces of a building.5.2.2 Additionally, the department of Housing and Urban Development (HUD) has the following standard for STC limitationsfor various housing units: HU
23、D Minimum Property Standards for Housing, Section 4910.1.6. Why Seal Openings?6.1 The sound transmission of a wall, ceiling, or floor, no matter how well built, can be substantially defeated by the presenceof unsealed joints, voids, and penetrations. Fig. 1 . This chart also shows the improvement of
24、 the STC when openings are sealed.It should be recognized for slit openings that the STC values may be different from the STC value for a hole opening.5.2Fig. 2 shows examples of how sound travels through openings in walls and how sealing may serve to minimize soundtransmission. Further examples may
25、 be found in Practice E497.illustrates examples of how sound travels through unsealed joints,voids, and penetrations in walls and how sealing them will minimize sound transmission.6.2 The effect of unsealed joints, voids, and penetrations on the STC rating of partition walls is illustrated in Fig. 2
26、6 For the sample wall example, with an STC rating of 40 that has openings that total 9 cm2(1.4 in.2) will have its STCreduced to 36 a 10 % difference. However, that small difference results in a change to the apparent loudness of soundtransmission to that which is twice as loud.7. Positioning of Sea
27、lants6.17.1 Fig. 3 illustrates placement of beads of sealant liquid-applied sealants to improve the STC rating from a value of 29 to avalue of 53. Note that two properly placed beadssealants are sufficient and sealing beyond that point is unnecessary.7.8. Application Method of Gunnable SealantSealan
28、ts7.18.1 Fig. 4 shows typical sealant applications.8.Types of Sealant for Acoustical Improvement8.1Preformed SealantsPreformed sealants include gasketing, tapes, and preformed foams. Most of these materials are effectiveonly when the tolerances of the perimeter joints can be accurately predicted and
29、 installed to those tolerances. Joint sizes varywidely and preformed sealants may have difficulty in maintaining a proper seal at all points with the constant compression thatis necessary to effect a seal. Preformed sealants in the form of pads have proved to be effective for sealing electric, telep
30、hone, andtelevision jack boxes.8.2Gunnable SealantsThese sealants have the capacity of conforming to the wide range of joint sizes encountered in mostconstruction. The following types are available:C919 1228.2.1Skinning and Drying SealantsSkinning and drying sealants such as asphalt- and oil-based c
31、aulking compounds performsatisfactorily initially but within a short period of time could begin to shrink, harden, crack, and lose adhesion, thereby losing theirFIG. 1 Examples of Achieving an Effective Sound Barrier andMaintaining the Designed STC Value of Partition SystemsFIG. 2 Effect of Unsealed
32、 Hole Openings on STC-Rated Test Wall,3.8by2.4m(12ft6in.by8ft)C919 123Edge DetailSTCValueCommentsuncaulked 29 the open-edge track gave the STC value of29 through direct leakageunsealed 29 the open-edge track gave the STC value of29 through direct leakagesingle bead at the perimeter of one baselayer4
33、9 this bead closed void but did not seal leak-age around the joint between the wallboardand tracksingle sealant at the perimeter of one baselayer49 this bead closed void but did not seal leak-age around the joint between the wallboardand tracktwo beads, one under each base layer ofgypsum board53 the
34、 beads closed void and sealed leakagearound tracktwo sealants, one for each base layer of gyp-sum board53 the beads closed void and sealed leakagearound trackfour beads, one under each base and facelayer of gypsum board53 the void is closed; no leaks around track andwallboardfour sealants, one for e
35、ach base and facelayer of gypsum board53 the void is closed; no leaks around track andwallboardNoteThe test partitions consisted of metal studs, 610 mm (24 in.) on center, with double layers of 13-mm (0.5in.) wallboard screw-attached to each side. Soundattenuation blanket, 38 mm (1.5 in.), was place
36、d in the void. The partition panels were erected, shimmed out 3 mm (0.125 in.) at the periphery: top, bottom, andedges.NoteData were obtained from the United States Gypsum Co. Round Lake Acoustical Research Facilities from a study conducted in accordance with Test MethodE336.FIG. 3 Performance of a
37、Partition System Sealed with Single or Multiple BeadsC919 124effectiveness in providing a positive seal. Many of these sealants tend to stain the walls. Specification C570 references these sealanttypes.8.2.2illustrates typical liquid-applied sealant applications. Additional sealant application infor
38、mation can be obtained fromGuide C1193 and manufacturers literature for specific products and applications.9. Types of Sealants9.1 Precured SealantsPrecured sealants include a wide variety of gaskets and tapes, and foamed shapes that have constantdimensions. These materials are effective sound seals
39、 when the tolerances for joint, void, or penetration opening can be accuratelypredicted and installed within those tolerances. A varying opening width along its length, which exceeds those tolerances, willcause the gasket, tape or foamed shape to have difficulty in maintaining a proper seal at all p
40、oints with the constant compressionthat is necessary to effect a seal. Precured sealants in the form of pads have proved to be effective for sealing electric, telephone,television and other types of jack and back boxes.9.2 Non-Sag SealantsThese liquid-applied sealants can conform to the wide range o
41、f sizes encountered in joints, voids, andpenetrations especially those that have tolerances exceeding those applicable for precured sealants. The following types areavailable:(a)(b)(c)(d)FIG. 4 Typical Sealant ApplicationC919 1259.2.1 Nondrying, Nonhardening, Nonskinning SealantsOf all the products
42、evaluated to date, the nondrying, nonhardening,nonskinning types of sealant have proven to be the most effective in reducing sound transmission. By remaining indefinitelyflexible as well as permanently adhesive, they can maintain a positive airtight seal. These sealants normally are nonbleeding andw
43、ill not stain walls. The nonskinning materials should be used only in concealed areas. When used as exposed beads, they maystain through paint or pick up dirt.8.2.3Nonoxidizing, Skinning SealantsSealants that skin, retain flexibility, and maintain adhesion can be effective in reducingsound transmiss
44、ion. These sealants are preferred in exposed bead applications, as they readily accept paint and other finishes.8.2.4These types of sealants have proven to be effective in reducing sound transmission. By remaining flexible as well aspermanently adhesive, they can maintain an effective seal. These ty
45、pes of sealants, for acoustical applications, normally arenonbleeding and will not stain walls. The nonskinning materials should be used only in concealed areas. If however, they areexposed to view they are not paintable and may stain adjacent paint and other surfaces or pick up dirt.9.2.2 Skinning
46、SealantsLiquid-applied sealants that cure in-place, develop a surface skin, retain flexibility, and maintainadhesion can be effective in reducing sound transmission. These sealants are preferred in exposed applications and certain typescan readily accept paint and other finishes. The following types
47、 are available:9.2.2.1 Latex-Based SealantsLatex-based sealants that retain flexibility and maintain adhesion can be effective in reducingsound transmission. Specification C834 references these sealant types.8.2.5Chemically Curing Sealants Many chemically curing one- and two-part sealants are availa
48、ble. While normally used forexterior seals, they can be effectively used for interior sound reduction. Specification references these sealant types. Guide C1520refers to their paintability characteristics and requirements. These sealants are primarily used for joints, voids, or penetrations thatare
49、static and do not experience movement.9.2.2.2 Aerosol Foam SealantsPolyurethane and latex based formulations are available for the sealing of iregular joints,voids, and penetrations to limit sound transmission. Specification C1620 references these sealant types. Only those foams that havevery little or no leakage after installation as described by Test Method C1642, as referenced in C1620 should be used. Thesesealants are primarily used for joints, voids, or penetrations that are static.9.2.2.3 Elastomeric SealantsWhile normally used for sealing joints on t
