1.1本试验方法涵盖房间内声音衰减率的测量以及房间及其内容物的吸声计算。如此计算的吸声量可用于隔声试验方法的计算。 1.2该方法只能与公式中使用吸声对数的其他试验方法结合使用。对于在不取对数的情况下使用房间吸声的情况，它不够精确。 1.3对于材料和物体吸声的实验室测量，试验方法 C423 应使用。 1.4 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 评估建筑构件隔声性能的几种ASTM试验方法要求测量房间吸声量，作为程序的一部分。这些标准中的房间吸声量以10 log的形式出现在等式中( x / A. )，其中 x 是一个单位与相同的数量 A. ，米 2. . 使用等式1根据衰减率计算房间吸声。 选择了本标准的要求，因此只要在计算中使用吸声的对数，与房间吸声测量相关的不确定度将是可接受的小。 其他测试方法应明确规定使用该测试方法。 如果母标准中的测量要求与此处给出的不同，则应满足母标准中的要求。 当直接使用房间吸声率或衰减率来满足某些标准时，不得使用本试验方法，例如在不能过度混响的房间中，以便语音可理解。 笔记 1-获得的房间吸声的不确定度通常过高，需要额外测量。 任何配套标准均可规定使用本方法中的程序来确定房间中的衰减速率是否足够慢，以满足配套标准的要求。测量的衰减率仍应仅用于计算房间吸收的对数。

1.1 This test method covers the measurement of sound decay rate in rooms and the calculation of the sound absorption of the room and its contents. The sound absorption so calculated may be used in calculations in sound insulation test methods. 1.2 The method shall be used only in conjunction with other test methods where the logarithm of the sound absorption is used in formulas. It is not sufficiently precise for use in situations where room sound absorption is to be used without taking logarithms. 1.3 For laboratory measurements of the sound absorption of materials and objects, Test Method C423 should be used. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== Several ASTM test methods to evaluate the sound-insulating properties of building elements require the measurement of room sound absorption as part of the procedure. The room sound absorption in these standards appears in an equation in the form 10 log ( x / A ), where x is a quantity with the same units as A , m 2 . Room sound absorption is calculated from the decay rate using Eq 1. The requirements of this standard have been chosen so the uncertainty associated with the measurement of room sound absorption will be acceptably small so long as the logarithm of the absorption is being used in calculations. Other test methods should specify explicitly that they make use of this test method. Where measurement requirements in the parent standard differ from those given here, the requirements in the parent standard shall be satisfied. This test method shall not be used when room sound absorption or decay rate is to be used directly to satisfy some criterion, for example in a room that must not be overly reverberant so speech will be intelligible. Note 1—The uncertainty of the room sound absorption obtained will usually be too high and additional measurements are necessary. Any companion standard may specify the use of the procedures in this method for determining whether the decay rates in a room are slow enough to satisfy the requirements of the companion standard. The measured decay rates shall still be used only to calculate the logarithm of the room absorption.