1、Designation: C 919 02Standard Practice forUse of Sealants in Acoustical Applications1This standard is issued under the fixed designation C 919; 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
2、parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice is a guide for the use of sealants to reducethe sound transmission characteristics of interior walls, ceil-ings, and floors by pro
3、per application of sealants to joints,voids, and penetrations normally found in building construc-tion.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 this standard to establish appro-priate safety and h
4、ealth practices and determine the applica-bility 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.2. Referenced Documents2.1 ASTM Standards:C 570 Specification for Oil- and Resin-Ba
5、se Caulking Com-pound for Building Construction2C 634 Terminology Relating to Environmental Acoustics3C 834 Specification for Latex Sealants2C 920 Specification for Elastomeric Joint Sealants2E90 Test Method for Laboratory Measurement of AirborneSound Transmission Loss of Building Partitions3E 336 T
6、est Method for Measurement of Airborne SoundInsulation in Buildings3E 413 Classification for Rating Sound Insulation3E 497 Practice for Installing Sound-Isolating LightweightPartitions32.2 Federal Specifications:TT-S-1657 (COM-NBS) Interim Federal Specification forSealing CompoundSingle Component, B
7、utyl RubberBased, Solvent Release Type (for Buildings and OtherType of Construction)4TT-C-598C (COM-NBS) Interim Federal Specification forCaulking Compound, Oil and Resin Base Type (forBuilding Construction)42.3 DHUD Standards:HUD Minimum Property Standards for One and Two FamilyHousing, Section 490
8、0.15HUD Minimum Property Standard for Multi Family Hous-ing, Section 4910.15HUD Minimum Property Standard for Care Type Housing,Section 4920.153. Significance and Use3.1 Construction utilizing lightweight walls and floors canhave undesirable sound transmission characteristics if care isnot taken to
9、seal joints and voids that are common to this typeof construction. By sealing these penetrations the transmissionof sound can be diminished.4. Sound Transmission Class4.1 The construction industry has adopted Sound Transmis-sion Class (STC) units (defined in Definitions C 634) to ratethe sound barri
10、er properties of walls, ceilings, and floors. TheSTC is determined in accordance with Classification E 413.The test data are obtained in accordance with Test MethodsE90orE336.NOTE 1For example, The Department of Housing and Urban Devel-opment (DHUD) has issued the following three standards dealing w
11、ith theSTC limitation in various housing units:HUD Minimum Property Standard for One and Two Family Housing,Section 4900.1;HUD Minimum Property Standard for Multi Family Housing, Section4910.1; andHUD Minimum Property Standard for Care Type Housing, Section4920.15. Need to Seal Openings5.1 The effec
12、t of unsealed openings on the STC of partitionwalls is shown in Fig. 1. This chart also shows the improve-ment of the STC when openings are sealed. It should berecognized for slit openings that the STC values may bedifferent from the STC value for a hole opening.1This practice is under the jurisdict
13、ion of ASTM Committee C24 on BuildingSeals and Sealants and is the direct responsibility of Subcommittee C24.10 onSpecifications, Guides and Practices.Current edition approved Jan. 10, 2002. Published March 2002. Originallypublished as C 919 79. Last previous edition C 919 98.2Annual Book of ASTM St
14、andards, Vol 04.07.3Annual Book of ASTM Standards, Vol 04.06.4Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.5Available from Superintendent of Documents, U.S. Government PrintingOffice, Washington, DC 20402.1Copyright
15、 ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 Fig. 2 shows examples of how sound travels throughopenings in walls and how sealing may serve to minimizesound transmission. Further examples may be found in PracticeE 497.6. Positioning of S
16、ealants6.1 Fig. 3 illustrates placement of beads of sealant toimprove the STC from a value of 29 to a value of 53. Note thattwo properly placed beads are sufficient and sealing beyondthat point is unnecessary.7. Application Method of Gunnable Sealant7.1 Fig. 4 shows typical sealant applications.8. T
17、ypes of Sealant for Acoustical Improvement8.1 Preformed SealantsPreformed sealants include gas-keting, tapes, and preformed foams. Most of these materials areeffective only when the tolerances of the perimeter joints canbe accurately predicted and installed to those tolerances. Jointsizes vary widel
18、y and preformed sealants may have difficulty inmaintaining a proper seal at all points with the constantcompression that is necessary to effect a seal. Preformedsealants in the form of pads have proved to be effective forsealing electric, telephone, and television jack boxes.8.2 Gunnable SealantsThe
19、se sealants have the capacity ofconforming to the wide range of joint sizes encountered inmost construction. The following types are available:8.2.1 Skinning and Drying SealantsSkinning and dryingsealants such as asphalt- and oil-based caulking compoundsperform satisfactorily initially but within a
20、short period of timecould begin to shrink, harden, crack, and lose adhesion, therebylosing their effectiveness in providing a positive seal. Many ofthese sealants tend to stain the walls. Specification C 570 andFederal Specification TT-C-598C reference these sealant types.8.2.2 Nondrying, Nonhardeni
21、ng, Nonskinning SealantsOfall the products evaluated to date, the nondrying, nonharden-ing, nonskinning types of sealant have proven to be the mosteffective in reducing sound transmission. By remaining indefi-nitely flexible as well as permanently adhesive, they canmaintain a positive airtight seal.
22、 These sealants normally arenonbleeding and will not stain walls. The nonskinning mate-rials should be used only in concealed areas. When used asexposed beads, they may stain through paint or pick up dirt.Federal Specification TT-S-1657 references these sealant types.8.2.3 Nonoxidizing, Skinning Sea
23、lantsSealants that skin,retain flexibility, and maintain adhesion can be effective inreducing sound transmission. These sealants are preferred inexposed bead applications, as they readily accept paint andother finishes. Federal Specification TT-S-1657 referencesthese sealant types.8.2.4 Latex-Based
24、SealantsLatex-based sealants that re-tain flexibility and maintain adhesion can be effective inreducing sound transmission. Specification C 834 referencesthese sealant types.8.2.5 Chemically Curing SealantsMany chemically cur-ing one- and two-part sealants are available. While normallyused for exter
25、ior seals, they can be effectively used for interiorsound reduction. Specification C 920 and Federal Specifica-tions TT-S-227E, TT-S-230C, and TT-S-1543A reference thesesealant types.FIG. 1 Effect of Unsealed Hole Openings on STC-Rated Test Wall,3.8by2.4m(12ft6in.by8ft)FIG. 2 Examples of Achieving a
26、n Effective Sound Barrier andMaintaining the Designed STC Value of Partition SystemsC9190229. Paintability of Exposed Beads of Sealants9.1 Sealant beads are usually painted if they are exposed.Because of the wide variety of types and brands of interiorpaint and the variety of types and brands of sea
27、lants, on-sitepaintability and stain tests are recommended.9.2 Paint applied before the sealant has cured may crackduring the curing process of the sealants. A reasonable sealantcure time should be allowed before painting. The sealantmanufacturer should be consulted regarding the recommendedcure tim
28、e prior to painting. (Structural movement may causepaint to crack.)10. Keywords10.1 acoustical; sealants; sound transmissionEdge DetailSTCValueCommentsuncaulked 29 the open-edge track gave the STC value of29 through direct leakagesingle bead at the perimeter of one baselayer49 this bead closed void
29、but did not seal leak-age around the joint between the wallboardand tracktwo beads, one under each base layer ofgypsum 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 andwallboardNot
30、eThe 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 placed in the void. The partition panels were erected, shimmed out 3 mm (0.125 in.) at the periphery: t
31、op, bottom, andedges.NoteData were obtained from the United States Gypsum Co. Round Lake Acoustical Research Facilities from a study conducted in accordance with Test MethodE 336.FIG. 3 Performance of a Partition System Sealed with Single or Multiple BeadsC919023ASTM International takes no position
32、respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. 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.Th
33、is standard is subject to revision at any time by the responsible technical committee and must be reviewed 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 Int
34、ernational Headquarters. Your comments will receive careful consideration at a meeting of theresponsible 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
35、 below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, 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).(a)(b)(c)(d)FIG. 4 Typical Sealant ApplicationC919024
