ASA: Acoustical Society of America

ASA, the Acoustical Society of America, is a nonprofit organization that develops and publishes standards on acoustics, mechanical shock, noise and other associated subjects. Headquartered near New York City, United States, ASA is composed of nearly 7,000 members and is a founding member of the American Institute of Physics. ASA also serves as the administrator for the U.S. TAGs (United States Technical Advisory Group) to ISO/TCs 43 and 108 (International Organization for Standardization/Technical Committee) and to various subcommittees within each. Standards from ASA are available both individually, directly through the ANSI webstore, and as part of a Standards Subscription. If you or your organization are interested in easy, managed, online access to standards that can be shared, a Standards Subscription may be what you need - please contact us at: [email protected] or 1-212-642-4980 or Request Proposal Price.

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ANSI/ASA S12.2-2019

Criteria for Evaluating Room Noise

This Standard provides three primary methods for evaluating room noise: a survey method that employs the A-weighted sound level; an engineering method that employs expanded noise criteria (NC) curves; and a method for evaluating low-frequency fluctuating noise using room noise criterion (RNC) curves.

ANSI/ASA S3.6-2018

Specification for Audiometers

The audiometers covered in this specification are devices designed for use in determining the hearing threshold level of an individual in comparison with a chosen standard reference threshold level. This standard provides specifications and tolerances for pure tone, speech, and masking signals and describes the minimum test capabilities of different types of audiometers.

ANSI/ASA S3.1-1999 (R2018)

Maximum Permissible Ambient Noise Levels for Audiometric Test Rooms

This Standard species maximum permissible ambient noise levels (MPANLs) allowed in an audiometric test room that produce negligible masking (2 dB) of test signals presented at reference equivalent threshold levels specied in ANSI S3.6-1996 American National Standard Specication of Audiometers. The MPANLs are specied from 125 to 8000 Hz in octave and one-third octave band intervals for two audiometric testing conditions (ears covered and ears not covered) and for three test frequency ranges (125 to 8000 Hz, 250 to 8000 Hz, and 500 to 8000 Hz). The Standard is intended for use by all persons testing hearing and for distributors, installers, designers, and manufacturers of audiometric test rooms. This standard is a revision of ANSI S3.1-1991 American National Standard Maximum Permissible Ambient Noise Levels for Audiometric Test Rooms.

ANSI/ASA S3.5-1997 (R2017)

Methods for Calculation of the Speech Intelligibility Index

Defines a method for computing a physical measure that is highly correlated with the intelligibility of speech as evaluated by speech perception tests given a group of talkers and listeners. This measure is called the speech Intelligibility Index, SII. The SII is calculated from acoustical measurements of speech and noise.

ANSI/ASA S12.6-2016 (R2020)

Methods for Measuring the Real-Ear Attenuation of Hearing Protectors

This standard specifies laboratory-based procedures for measuring, analyzing, and reporting the passive noise-reducing capabilities of hearing protectors.

ANSI/ASA S2.26-2001 (R2016)

American National Standard Vibration Testing requirements and Acceptance Criteria for Shipboard Equipment

This national standard defines vibration test requirements for shipboard equipment and machinery components. The tests are intended to locate resonances of the equipment and impose endurance tests at these frequencies, if any. The frequency range of the tests is 4 Hz to 50 Hz (100 Hz for reciprocating machinery-mounted equipment).

ANSI ASA S3.22-2014 (R2020)

Specification of Hearing Aid Characteristics

This standard describes hearing aid measurements that are particularly suitable for specification and tolerance purposes.

ANSI/ASA S12.42-2010 (R2020)

Methods for the Measurement of Insertion Loss of Hearing Protection Devices in Continuous or Impulsive Noise Using Microphone-in-Real-Ear or Acoustic Test Fixture Procedures

This standard provides methods for the measurement of the insertion loss of hearing protection devices in specified continuous and impulsive noise environments. The microphone-in-real-ear (MIRE) method utilizes human test subjects and may be used for hearing protectors that enclose the ears and make supra-aural or circumaural contact with the head, whereas the acoustical test fixture (ATF) method employs an inanimate fixture and can be used for any hearing protection device. The standard contains information on instrumentation, calibration, and electroacoustic requirements including details regarding the sound field of test facilities, the acoustical characteristics of ATFs, and subject selection and training and location of ear-mounted microphones for MIRE testing. Methods for measuring or determining sound pressure levels in the ear are also specified as well as methods for reporting the calculated insertion loss.

ANSI/ASA S2.75-2017/Part 1

Shaft Alignment Methodology, Part 1: General Principles, Methods, Practices, and Tolerances

Establishes methodology consistent with industry best practices for the measurement, analysis, and correction of alignment of shafts on rotating machinery coupled by means of a flexible coupling where such shafts are supported by two bearings in independent, horizontally mounted machine cases. Electric motors driving a pump, fan, or similar machine are examples of this type of machinery. Rigidly coupled machines are outside of the scope of Part 1 of this standard.

ANSI/ASA S1.13-2020

Measurement of Sound Pressure Levels in Air

This standard specifies requirements and describes procedures for the measurement of sound pressure levels in air at a single point in space. These requirements and procedures apply primarily to measurements performed indoors but may be utilized in outdoor measurements under specified conditions. This is a standard applicable to a wide range of measurements and to sounds that may differ widely in temporal and spectral characteristics; more specific American National Standards complement its requirements. This standard applies only to the measurement of continuous sounds, those whose duration is 1 second or greater and does not apply to the measurement of impulsive sounds whose duration is less than 1 second. This standard is intended to be used by practitioners in the field. This is a replacement for a previous version of ANSI S1.13.