ASTM E1042-02(R2021) pdf free download
ASTM E1042-02(R2021) pdf free download.Standard Classification for Acoustically Absorptive Materials Applied by Trowel or Spray
3. Terminology
3.1 Definitions: 3.1.1 The acoustical terminology used in this classification is consistent with Terminology C634. 3.1.2 Sound absorption average (SAA)—a single number rating, the average, rounded off to the nearest 0.01, of the sound absorption coefficients of a material for the twelve one-third octave bands from 200 through 2500 Hz, inclusive, measured according to Test Method C423.
4. Significance and Use
4.1 Acoustically absorptive materials are used for the con- trol of reverberation and echoes in rooms. This standard provides a classification method for acoustically absorptive materials applied directly to surfaces by trowel or by spray.
5. Basis of Classification
5.1 Classification is made according to type of material, acoustical properties, flame spread, and dust propensity. 5.2 Material Type—Classification of acoustically absorptive material according to material type is as follows: 5.2.1 Type I—Material is cementitious. Type I ingredients shall be uniformly mixed and ready for use by the addition of water. When received, the material in the container shall be dry and shall not be caked or sticky. After the material has been properly mixed with the amount of water specified by the manufacturer, the material shall be ofsuch a consistency that it can be applied with a plastering trowel or with a suitable plaster-spraying machine. 5.2.2 Type II, Material is fibrous. Type II material shall consist of mineral or organic fiber with an integrally mixed binder, or it may be supplied for use with a liquid binder added at the time of application. 5.2.3 Type III, Material is cellular plastic and is intended for application over beams, walls, ceilings, and columns. Type III materials are normally designed to be mixed at the time of application. 5.3 Noise Reduction Coeffıcient—Classification of acousti- cally absorptive material according to its noise reduction coefficient (NRC) shall be as follows:N OTE 1—Because sound absorption varies with product thickness, information on the required thickness and measurement method for a particular grade must be supplied by the manufacturer. N OTE 2—Determine NRC or SAA values in accordance with 6.1. N OTE 3—Since SAA is replacing NRC, SAAvalues may be used in lieu of NRC when rating material according to this standard classification. However, the NRC nomenclature is retained as the classification label. It is recommended that ratings based on newly acquired absorption data use SAA. Ratings based on data measured before Test Method C423 required SAA may use NRC. See Test Method C423 for more discussion of NRC and SAA. 5.4 Flame Spread Index—Acoustically absorptive material shall be classified according to its flame spread index as follows: 5.4.1 Class (a)—The flame-spread index of the acoustical material shall not exceed 25 when tested in accordance with Test Method E84, nor shall the material show evidence of progressive combustion after the test flame is extinguished. All surfaces, including those which would be exposed by cutting through the material in any way, shall meet these requirements. In addition, Class (a) materials shall have a smoke developed rating not to exceed 50 when tested in accordance with Test Method E84. 5.4.2 Class (b)—The flame-spread index shall not exceed 75 on the exposed surface when tested in accordance with Test Method E84.5.4.3 Class (c)—The flame-spread index shall not exceed 200 on the exposed surface when tested in accordance with Test Method E84. N OTE 4—For example: AType II, NRC 50, at x cm (y in.) ofapplication class (b) material is fibrous, has an NRC of 0.5 or and has a flame-spread index of less than 75. The value for x (and y) must be specified by the manufacturer. 5.5 Dust Propensity—Classification of acoustically absorp- tive material according to its dust propensity shall be as follows: 5.5.1 Category A—Dust removed shall not exceed 0.27 g/m 2 when tested in accordance with Test Method E859. 5.5.2 Category B—Dust removed is greater than 0.27 g/m 2 when tested in accordance with Test Method E859. N OTE 5—Classification according to dust propensity is usually specified only by certain agencies of the US Government.