E33.05 - Research

SIGNIFICANCE AND USE
5.1 ASTM standard test methods that involve sound attenuation and those test methods that involve absorption or decay rates use a noise signal to determine these quantities. The IR method using a sweep signal given in this standard practice can be referenced by these other standards to provide an alternative measurement technique. This alternative technique has the advantage of providing more reliable results in a shorter period of time.  
5.2 The results obtained with the noise and IR method are considered identical to within the typical measurement uncertainty for the noise method under repeatability conditions. A mandatory validation procedure is given in this practice to ensure a correct implementation of the IR method when developing software or hardware according to the requirements in this standard.  
5.3 To avoid ambiguity in the implementation of the IR method and to ensure consistent results across different users, this practice prescribes the values of methods and parameters to be used in the signal generation and post-processing. This is in contrast to similar standards describing this method, such as ISO 18233, which provide less guidance.
SCOPE
1.1 This practice covers the impulse response measurement method using sweep signals, and its use to determine two important room-acoustical quantities: the difference in sound pressure levels between two positions, as used for example in standards determining transmission loss; and decay curves, as used in standards determining the decay rate or reverberation time.  
1.2 The practice shall be used in conjunction with test methods that use one or both of the quantities described in 1.1.  
1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This specification covers measurement systems used in making sound pressure level measurements in buildings in accordance with ASTM standards and guides. The measurement system includes all the components necessary to indicate measured sound pressure levels, such as microphones, preamplifiers, cables, processing units, filters, computers, display units, and other peripheral devices. Where the system is composed of components, specifications are given for microphone type and orientation, filters and windscreens. This specification does not cover systems for making sound pressure level measurements in other environments, but may include these environments in the future. Performance criteria required for measurement of sound pressure levels in building acoustics are addressed in this specification, along with the requirements for measurements systems which are not designed to conform to a normative sound level meter performance standard.
SCOPE
1.1 This specification is for measurement systems used in making sound pressure level measurements in buildings in accordance with ASTM standards and guides. Systems for making sound pressure level measurements in other environments are not addressed in this specification. A future expansion of this specification may include these environments. The systems addressed include one or more microphones and associated components to process the output of the microphone measurement system conforms to a sound level meter specification it is sufficient to specify the category of precision and accuracy required by the measurement system and that direction is given in the user manual for proper use. Where the system is composed of components, specifications are given for microphone type and orientation, filters and windscreens.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 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.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SCOPE
1.1 This guide is intended to assist acoustical standards-writing groups in the preparation of laboratory accreditation annexes for acoustical test standards (see 4.2.1).
WITHDRAWN RATIONALE
Formerly under the jurisdiction of Committee E33 on Building and Environmental Acoustics, this guide was withdrawn in January 2008 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.