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NBS SPECIAL PUBLICATION 386

1976 EDITION

U.S. DEPARTMENT OF COMMERCE / National Bureau of Standards

Standards on Noise M

Rating Schemes, an

A Compilation

finitions:

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NATIONAL BUREAU OF STANDARDS

The National Bureau of Standards' was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology

and facilitate their effective application for public benefit. To this end, the Bureau conducts

research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research, the Institute for Applied Technology,

the Institute for Computer Sciences and Technology, and the Office for Information Programs.

THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United

States of a complete and consistent system of physical measurement; coordinates that system

with measurement systems of other nations; and furnishes essential services leading to accurate and uniform physical measurements throughout the Nation's scientific community, industry,

and commerce. The Institute consists of the Office of Measurement Services, the Office of Radiation Measurement and the following Center and divisions:

Applied Mathematics — Electricity — Mechanics — Heat — Optical Physics — Center

for Radiation Research: Nuclear Sciences; Applied Radiation — Laboratory Astrophysics" — Cryogenics - —• Electromagnetics " — Time and Frequency -. THE INSTITUTE FOR MATERIALS RESEARCH conducts materials research leading to improved methods of measurement, standards, and data on the properties of well-characterized

materials needed by industry, commerce, educational institutions, and Government; provides

advisory and research services to other Government agencies; and develops, produces, and

distributes standard reference materials. The Institute consists of the Office of Standard

Reference Materials, the Office of Air and Water Measurement, and the following divisions:

Analytical Chemistry — Polymers — Metallurgy — Inorganic Materials — Reactor

Radiation — Physical Chemistry.

THE INSTITUTE FOR APPLIED TECHNOLOGY provides technical services to promote

the use of available technology and to facilitate technological innovation in industry and Government; cooperates with public and private organizations leading to the development of technological standards (including mandatory safety standards), codes and methods of test; and provides technical advice and services to Government agencies upon request. The Insti- tute consists of the following divisions and Centers: Standards Application and Analysis — Electronic Technology — Center for Consumer

Product Technology: Product Systems Analysis; Product Engineering — Center for Building

Technology: Structures, Materials, and Life Safety; Building Environment; Technical Evaluation and Application — Center for Fire Research: Fire Science; Fire Safety Engineering.

THE INSTITUTE FOR COMPUTER SCIENCES AND TECHNOLOGY conducts research and provides technical services designed to aid Government agencies in improving cost effec- tiveness in the conduct of their programs through the selection, acquisition, and effective utilization of automatic data processing equipment; and serves as the principal focus within

the executive branch for the development of Federal standards for automatic data processing

equipment, techniques, and computer languages. The Institute consists of the following

divisions: Computer Services — Systems and Software — Computer Systems Engineering — Information Technology.

THE OFFICE FOR INFORMATION PROGRAMS promotes optimum dissemination and

accessibility of scientific information generated within NBS and other agencies of the Federal Government; promotes the development of the National Standard Reference Data System and

a system of information analysis centers dealing with the broader aspects of the National Measurement System; provides appropriate services to ensure that the NBS staff has optimum

accessibility to the scientific information of the world. The Office consists of the following

organizational units: Office of Standard Reference Data — Office of Information Activities — Office of Technical

Publications — Library — Office of International Relations — Office of International Standards.

1 Headquarters and Laboratories at Gaithersburg, Maryland, unless otherwise noted; mailing address Washington, D.C. 20234.

3 Located at Boulder, Colorado 80302.
standards on Noise Measurements,

Rating Schemes, and Definitions:

A Compilation

Thomas L. Quindry, Editor

Applied Acoustics Section

Institute for Basic Standards

National Bureau of Standards

Washington, D.C. 20234

U.S. DEPARTMENT OF COMMERCE, Elliot L. Richardson, Secretary

James A. Baker, III, Under Secretary

Dr. Betsy Ancker-Johnson, Assislani Secretary for Science and Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Acting Director

Issued April 1976
Library of Congress Catalog Card Number: 73-600305

National Bureau of Standards Special Publication 386

Nat. Bur. Stand. (U.S.), Spec. Publ. 386, 1976 Edition, 84 pages (Apr. 1976) CODEN: XNBSAV

Supersedes NBS Special Publication 386, 1973 Edition

U.S. GOVERNMENT PRINTING OFFICE

WASHINGTON: 1976

For sale by tlie Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 (Order by SD Catalog No. C13.10:386). Price $1.90. (Add 25 percent additional for other than U.S. mailing).
Abstract

This compilation deals with material assembled from the various standards, industrial

1 knd trade organizations, or technical and scientific societies concerned with acoustics,

rhere has been no attempt to review or evaluate the standards, but rather just to list

documents covering measurement techniques, calibration methods, definitions, rating

schemes, and equipment and product specifications concerned with noise. Those standards

dealing solely with ultrasonics, audio equipment, or shock and vibration have not generally

been included. The paragraphs describing the standards give a brief summary of intent

and/or scope of the standard. In some cases the paragraph is the official description of

the standard as issued by the organization or society promulgating the standard, while in

others the paragraph merely describes the intent of the standard. Proposed standards are

also listed where available. Not listed are proposed revisions of current standards and

those which must be reapproved to remain in effect. For the convenience of those readers

wishing to purchase copies of standards, names and addresses for the various organizations

and/or societies are provided. Federal Regulations directly involving noise measurements

are given in Appendix A. Appendix B lists active committees for each organization and

names and addresses of appropriate committee chairmen or technical contacts. This

compilation includes all information available as of January 1, 1976.

Key Words: Acoustics; noise; rating scheme; sound; standards organization.

Acknowledgement

The Applied Acoustics Section wishes to thank William J. Slattery, Manager, Standards

Information Services, Standards Information and Analysis Section, Standards Application and

Analysis Division, Institute for Applied Technology, NBS for his assistance in locating and

acquiring many of the standards which are summarized in this document.

iii

Preface

The existence of satisfactory standards and mechanisms for generating them are

essential for the appropriate use of a country's technology in its commercial products and

industrial processes. Standards deal with techniques for physical measurements,

descriptive terminology, methods of test and agreements on dimensions, design, performance

and physical characteristics dealing with products that are manufactured and sold. These

latter standards are referred to as engineering or industrial standards which usually

include more specific types of standards such as product standards, commercial standards

and safety standards. The majority of these standards are normally not a matter of law and

most are developed in the private sector. Exceptions usually occur in areas of health and

safety. The use of such standards is voluntary but their widespread acceptance can often

give them considerable commercial importance. The Government does issue mandatory

standards as exemplified by those in the areas of pollution control and abatement, fabric

flammability , and toy safety. Widely accepted standards can become mandatory when

incorporated into contracts, codes and regulations.

There have been a number of recent legislative actions that give impetus and a sense

of urgency to the development of standards and measurement methods that are needed for the

effective implementation of a national program on noise pollution abatement and control.

While the laws which have been enacted rarely call specifically for new or improved

measurement standards, regulations can be enforced most effectively when based upon a fair,

equitable, and uniform measurement methodology.

As part of its response to the measurement needs created by the concern over noise,

its abatement, and control, NBS has prepared this compilation. Standards dealing

specifically with noise plus those which are clearly germane to noise measurements have

been included. However, this document does not include all standards dealing in part with

acoustics. For example, there has been no attempt to include safety standards which

incorporate a noise test as one of the many required measurements.

V

Table of Contents

Page

1. Acoustical and Board Products Association (ABPA) 1

I. 1 Summary of Standards i

2. Acoustical Society of America (ASA) ^ 2

2.1 Summary of Standards 2

3. Air -Conditioning and Refrigeration Institute (ARI) 3

3.1 Summary of Standards 3

4. Air Diffusion Council (ADC) 5

4.1 Summary of Standards 5

5. Air Moving and Conditioning Association (AMCA) 6

5.1 Summary of Standards 6

6. American Gear Manufacturers Association (AGMA) 8

6.1 Summary of Standards 8

7. American National Standards Institute (ANSI) 9

7.1 Summary of Standards 9 7.2 Draft Proposals for New Standards 14

8. American Society of Heating, Refrigerating, and Air Conditioning 15

Engineers (ASHRAE)

8.1 Summary of Standards 15

9. American Society for Testing and Materials (ASTM) 16

9.1 Summary of Standards 16

9.2 Draft Proposals for New Standards 18

10. American Textile Machinery Association (ATMA) 19

10.1 Summary of Standards 19

11. Anti-Friction Bearing Manufacturers Association (AFBMA) 20

II. 1 Summary of Standards 20

12. Association of Home Appliance Manufacturers (AHAM) 21

12.1 Summary of Standards 21

12.2 Draft Proposals for New Standards 21

13. Compressed Air and Gas Institute (CAGI) 22

13.1 Summary of Standards 22

14. Diesel Engine Manufacturers Association (DEMA) 23

14.1 Summary of Standards 23

vii
Page

15. Electronic Industries Association (EIA) 24

15.1 Summary of Standards 24

16. Federal Construction Guide Specification (FCGS) , ,

. .• 25

16.1 Summary of Standards . 25

17. Federal Specifications 26

17.1 Summary of Standards . , 26

18. Home Ventilating Institute (HVI) .

. ., .. .. 27

18.1 Summary of Standards '

' 27

19. Industrial Silencer Manufacturers Association (ISMA) •

' 28

19.1 Summary of Standards > 19.2 Draft Proposals for New Standards 28

20. Institute of Electrical and Electronic Engineers (IEEE) , 29

20.1 Summary of Standards . 29

21. Instrument Society of America (ISA) 30

21.1 Summary of Standards 30

22. International Conference of Building Officials (ICBO) 31

22.1 Summary of Standards 31

23. International Electrotechnical Commission (lEC) 32

23.1 Summary of Standards 32

23.2 Draft Proposals for New Standards 36

24. International Organization for Standardization (ISO) 37

24.1 Summary of Standards 37 24.2 Draft Proposals for New Standards 43

25. Military Specifications 45

25.1 Summary of Standards 45

26. National Electrical Manufacturers Association (NEMA) 47

26.1 Summary of Standards 47

27. National Fluid Power Association (NFPA) 48

27.1 Summary of Standards 48

27.2 Draft Proposals for New Standards 48

28. National Machine Tool Builders Association (NMTBA) 49

28.1 Summary of Standards "^9

29. National School Supply and Equipment Association (NSSEA) 50

viii
Page

29.1 Summary of Standards ' 50

30. Power Saw Manufacturers Association (PSMA) ' 51

30.1 Summary of Standards 51

31. Public Building Service (PBS) '52

31.1 Summary of Standards 52

32. Society of Automotive Engineers (SAE) 54

32.1 Summary of Standards • . 54

32.2 Draft Proposals for New Standards 59

33. Steel Door Institute (SDI) 61

33.1 Summary of Standards 61

34. Woodworking Machinery Manufacturers Association (WMMA) 62

34.1 Summary of Standards 62

Appendix A. Summary of Federal Regulations ' 63

Appendix B. Committees/Technical Contacts " 68

ix

1 . Acoustical and Board Products Association (ABPA)

[formerly Acoustical and Insulating Materials Association (AIMA)

Purchase standards from:

Acoustical and Board Products Association

205 West Touhy Avenue

Park Ridge, XL 60068

1 .1 Summary of Standards

1.1 AMA-l-II-1967. METHOD OF TEST. CEILING SOUND TRANSMISSION TEST BY TWO-ROOM

METHOD.

This is a performance test for a conf Iguratlonal property of celling

constructions, without explicit reference to the sound absorption coefficients or sound transmission loss of ceiling materials. In particular, performance is

rendered Independent of the total In-sltu absorption contribution of the

receiving-room celling under test conditions by normalizing results with respect

to separate measurements specified herein, thereby focusing attention upon the

relative energy transmission of the celling configuration without appeal to absorption coefficients. The method of test is designed to reflect field

conditions of celling erection under laboratory conditions of measurement control,

without necessary restriction to standardized classes of celling construction

beyond convenience for material comparisons.

The method of test is Intended primarily for ranking the sound isolation

performance of suspended-ceiling configurations in a specific test environment,

generalized only with respect to receiving room absorption toward the ultimate

objective of relating celling rankings quantitatively to partition-test rankings

under widely varying field situations.

1.2 AM SPEC. NO. 11. (1972) ACOUSTICAL ABSORBERS.

The purpose of this Standard is to establish a uniform set of practices for

the testing of Unit Acoustical Absorbers "surface-type" which will supplement the

requirements of the American Society for Testing and Materials Designation:

C423-66, Standard Method of Test for SOUND ABSORPTION OF ACOUSTICAL MATERIALS IN REVERBERATION ROOMS, or its latest revision.

Unit Acoustical Absorbers "surface-type" are defined for the purpose of this

standard as elements of acoustical material differing from other sound absorbing

materials only in distribution during use.

1
2 . Acoustical Society of America (ASA)

Purchase Standards from:

Back Numbers Dept., Dept. Std.

American Institute of Physics

335 East 45th Street

New York, NY 10017

2.1 Summary of Standards

2.1.1 ASA STD 1-1975 METHOD FOR THE MEASUREMENT OF REAL-EAR PROTECTION OF HEARING

PROTECTORS AND PHYSICAL ATTENUATION OF EARMUFFS.

See ANSI S3. 19-1974. ...

2.1.2 ASA STD 3-1975 TEST-SITE MEASUREMENT OF NOISE EMITTED BY ENGINE POWERED . EQUIPMENT.

This Standard presents test-site measurement methods for determining the

maximum noise emitted by motor vehicles, public conveyances, construction and

industrial machinery, and residential and recreational devices powered by engines

operating on petroleum-based fuels, coal, steam, electricity, or other source of

energy. It strives for simplicity of measurement technique, with regard for

realistic operation of the equipment being tested and for reproducibility of test

results. The test methods are intended for application to certification testing

by the manufacturer, conformance testing by community agencies, and survey testing

for community noise intrusion. This Standard is not intended as a basis for

enforcement purposes at any location other than a qualified test site.

Specifically recognized as sources of community noise and included for

coverage by this document are: automobiles; trucks of all types; multipurpose or utility vehicles; motorcycles and motorscooters ; buses and motor-coaches; all

railbound vehicles; engine-powered mobile equipment intended for use in

residential areas (e.g., lawnmowers, snow removers, chain saws, etc.); and

engine-powered recreational equipment (e.g., motorboats, snowmobiles, etc.).

Corventional full-scale aircraft are excluded from coverage, although guidelines

for measuring noise from model aircraft, rotary-wing aircraft, and ground-effect

machines (hovercraft) are included. The procedures are not limited to this

listing of equipment and are applicable to other engine-powered equipment which

can also be categorized as contributing to community noise.

It is not the intent of this Standard to specify maximum permissible sound

levels for any equipment. It is, however, recommended that A-weighted sound

levels, when measured in accordance with this Standard, be specified for these

limits. The use of sound levels for specifying the noise of engine-powered

equipment does not preclude detailed frequency analyses as may be required for

noise control studies, provided that the sound level data are also reported.

2.1.3 ASA STD 4-1975 METHOD FOR RATING THE SOUND POWER SPECTRA OF SMALL STATIONARY

NOISE SOURCES (ANSI S3. 17-1975).

The purpose of this standard is to establish a uniform method for rating the

noise of sm^ll stationary equipment using sound power spectrum. This standard

applies to all equipment which is essentially stationary in nature and for which a sound power spectrum may be determined. It is designed for products used in and

about homes, and includes equipment normally used in connection with the operation

and maintenance of a home or business. This standard deals with the method for

rating and reporting the noise of such equipment.

2
3 . Air-Conditloning and Refrigeration Institute (ARI)

Purchase standards from:

Air-Conditioning and Refrigeration Institute

1815 North Fort Myer Drive

Arlington, VA 22209

3.1. Summary of Standards

3.1.1 ARI STANDARD 270 (1967) STANDARD FOR SOUND RATING OF OUTDOOR UNITARY EQUIPMENT.

ARI has produced this Standard in order to provide the industry and the

public with a procedure for rating and evaluating the sound levels of outdoor

unitary equipment. The rating numbers may be used to predict expected sound

pressure levels in a specific acoustical environment at a given distance. A

recommended procedure for accomplishing this will be described in a related ARI

application standard.

In this Standard, the rating of equipment, as obtained at specified Standard

Operating Conditions, is in the form of single numbers, designated as ARI Standard

Sound Rating Numbers.

For a specific model of outdoor unitary equipment, an ARI Standard Sound

Rating Number is developed from basic acoustic measurements made as prescribed in

ASHRAE Standards 36-62* or 36A-63*, as applicable. These measured one-third

octave band power levels are weighted to adjust for psychoacoustic sensitivity to frequency distribution and any discrete tones which may be present and then are converted to an ARI Standard Sound Rating Number.

3.1.2 ARI STANDARD 2 75 (1969) STANDARD FOR APPLICATION OF SOUND RATED OUTDOOR UNITARY

EQUIPMENT

This standard provides a method of predicting the sound level resulting from

the operation of outdoor sections of unitary air-conditioning and heat pump

equipment. A simple step-by-step procedure is given which uses a sound rating

number for the equipment, and the distance to the point at which equipment noise

is to be predicted. The nature of the surroundings and of the installation is

also taken into account.

The sound rating number is adjusted for these installation factors to establish a sound level number (SLN) which is used in an alignment chart to predict, for a specific location, a tone-corrected sound level which is intended

to be a predictor of annoyance due to the sound. The annoyance level can be

calculated precisely in the manner specified in the Appendix, from one-third

octave band sound pressure levels measured at the point in question. It may be

estimated (normally within dB) from measurements of the A-weighted sound level.

If desired, the NC level of the sound may also be estimated from the alignment

chart. The accuracy of the prediction is dependent upon other application

variables; i.e., the directivity of the sound from the unit and, to some degree,

the spectrum of the sound from the unit.

Examples are used to clarify the procedure and recommended practices are presented to guide the acoustic considerations of air-conditioning equipment

installations.

This Standard shall not be used for determining the sound rating number of

outdoor unitary equipment.

3.1.3 ARI STANDARD 443 (1970) STANDARD FOR SOUND RATING OF ROOM FAN-COIL

AIR-CONDITIONERS.

ARI has produced this standard to fulfill a growing need for a reliable

method of sound rating room fan-coil air-conditioners.

3
This Method of rating is based upon tests conducted in accordance with ASHRAE

Standard 36-62*, which gives test results for sound power levels. The acoustic

output can best be defined by sound power levels, since these quantities are independent of the many environments in which the equipment may be used. Sound

power levels may be used to predict the sound pressure levels that will result in

a space of known acoustical characteristics.

It is recognized that room fan-coil air-conditioners and most other

air-conditioning equipment produce complex sound spectra which may not be suitably

rated from broad band measurements alone. The annoyance of pure tones, for

example, is not reflected in octave band measurements. Consequently, this

Standard requires measurements by one-third octave bands and applies subjective

corrections based on extensive research in order to arrive at meaningful ratings.

3.1.4 ARI STANDARD 446 (1968) STANDARDS FOR SOUND RATING OF ROOM AIR-INDUCTION UNITS.

ARI has produced this Standard to fulfill a growing need for a reliable

method of sound rating room air-induction units.

The relationship between this Standard and ASHRAE 36B-63* is analogous to the

relationship between ARI 443 and ASHRAE 36-62*.

It should also be recognized that the sound power levels of room

air- induction units will vary as functions of both the primary air quantity and

the damper pressure drop. Therefore, the Standard Rating Conditions of this

Standard include a specified damper pressure drop.

3.1.5 ARI STANDARD 575 (1973) STANDARD FOR METHOD OF MEASURING MACHINERY SOUND WITHIN

EQUIPMENT ROOMS.

The purpose of this standard is to establish a uniform method of measuring,

recording and specifying the sound pressure level of machinery installed in

mechanical equipment spaces.

This standard applies to water chilling systems, pumps, and similar operating

machines and parts thereof, which for reasons of size or operating problems cannot

practically be evaluated by the procedures of ASHRAE Standard Methods of Testing

for Sound Rating Heating, Refrigerating and Air-Conditioning Equipment (American

Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. Standard

36-72).

*Several of these Standards reference ASHRAE Standards 36-62, 36A-63 and 36B-63

which have been superseded by ASHRAE Standard 36-72, Methods of Testing for Sound

Rating Heating, Refrigerating and Air-Conditioning Equipment.

4
4. Air Diffusion Council (ADC)

Purchase standards from:

Air Diffusion Council

435 North Michigan

Chicago, IL 60611

4.1. Summary of Standards

14.1.1 ADC 1062R3 (1972) EQUIPMENT TEST CODE (REPLACES 1062R2)

This Test Code is intended to provide a means for testing and rating air

distribution and control devices. It should provide a basis for comparison among

the available equipment and also for determining the comfort conditions of

occupied rooms in air conditioning, heating and ventilating systems.

The purpose of this Test Code is to present in a single document all those

techniques and facilities required for the measurement of performance of air

distribution or air terminal devices. Methods of Test Measurement have been

established to provide uniform test procedures, equipment and instrumentation with

regard to air flow, velocity and pressure, temperature and sound generation. The

sound measuring instrumentation and tests for determining the sound generated are

in accordance with ANSI and ASHRAE Standards.

4.1.2 AD-63 (1963) MEASUREMENT OF ROOM-TO-ROOM SOUND TRANSMISSION THROUGH PLENUM AIR

SYSTEMS

The purpose of the measurements covered by this Standard is tc determine the

sound transmission along a complex path, the incident side or area of which is an opening (which may be fitted with a grille or similar device), the transmitting

side or area of which is an identical opening, the intervening element of which is

a ceiling plenum whose characteristics are hereinafter described. Such paths are commonly used for unducted air handling systems in buildings.

This standard establishes the requirements for the determination and

presentation of air friction loss, leakage, and sound data for flexible air

ducting used as a means of conveying conditioned air in heating and air

conditioning systems. Requirements are established for the selection and

preparation of test specimens, the test equipment and procedures to be used, the

installation of test specimens, the accumulation of test data, and the format for

presentation of results.

4.1.3 FD-72 (1972) FLEXIBLE AIR DUCT TEST CODE.

5
5 . Air Koviug and Conditioning Association (AMCA)

Purchase standards from:

Air Moving and Conditioning Association

30 West University Drive

Arlington Heights, IL 60004

5.1. Summary of Standards

5.1.1 AMCA STANDARD 300-67 TEST CODE FOR SOUND RATING.

This Code establishes a practical method of determining the sound power level

of an Air Moving Device (AMD). The Code will: (a) Present values that are useful

in field applications. (b) Give uniformly reproducible results in all qualified

laboratories. (c) Be "practical" in the sense that its accuracy will be satisfactory for all general applications while its operation will not add

significantly to the cost of the product.

These aims are achieved by applying standard, readily available sound

measuring instruments to reverberant or semi-reverberant room with minimal

restrictions on size and construction. The test set-ups are designed to represent

genera] usage of the AMDs tested.

5.1.2 AMCA BULLETIN 301 (1965) STANDARD METHOD OF PUBLISHING SOUND RATINGS FOR AIR

MOVING DEVICES.

This document establishes a standard method of publishing Sound Ratings for

Air Moving Devices. The purpose of this Standard is to eliminate

misunderstandings between the manufacturer and the purchaser and to assist the

purchaser in selecting and obtaining the proper product for his particular need.

This Standard applies to: (a) Centrifugal Fans. (b) Axial and Propeller

Fans. (c) Power Roof and Wall Ventilators. (d) Steam and Hot Water Unit Heaters.

It is intended that this Standard shall also apply to Central Station Heating,

Ventilating and Air Conditioning Units.

5.1.3 AMCA BULLETIN 302 (1965) APPLICATION OF SONE LOUDNESS RATINGS FOR NONDUCTED AIR

MOVING DEVICES.

The AMCA method of rating in sones gives the loudness at a distance of 5 feet

from the unit in free space with no nearby reflecting surfaces. Since most

practical problems will involve the judgment of loudness within a room, some method is needed to relate the loudness in a given room to the "loudness rating"

of the fan.

The charts and formulae given in this bulletin are for the purpose of

determining the loudness of fans as installed, and take into consideration the room size and acoustical qualities as well as the number and ratings of the fans.

Within the range of 3.5 and 38 sones, these charts are mathematically rigorous,

and are sufficiently accurate for engineering applications from 1.5 to 85 sones.

For the addition of sounds, it is assumed that the noise spectrums are similar.

The room effect chart is for the reverberant field in the room, and applies

everywhere except in the space very near to the fan.

5.1.4 AMCA PUBLICATION 303 (1965) APPLICATION OF SOUND POWER RATINGS FOR DUCTED AIR

MOVING DEVICES.

AMCA Sound Power Level Ratings are indicators of the sound generated by an Air Moving Device when operated at various points within its normal operating

range. The ratings are obtained from tests conducted by the method described in

AMCA Standard 300, Test Code for Sound Rating AMDs, and are published in

accordance with AMCA Standard 301, Method of Publishing Sound Ratings for AMDs.

6
Air Moving Devices that are normally used without ducts are rated in sones

Information on the use of sone ratings is given in AMCA Publication 302,

Application of Sone Loudness Ratings.

5.1.5 AMCA PUBLICATION 311-67 CERTIFIED SOUND RATINGS PROGRAM FOR AIR MOVING DEVICES.

The purpose of the Certified Sound Ratings Program is to give the buyer,

specifier, and user of air moving equipment increased assurance that published

sound ratings are reliable. At the same time, the Program establishes standard

testing and rating methods and assures the manufacturer that competitive racings

have been checked by an impartial authority.

7
6 . American Gear Manufacturers Association (AGMA)

Purchase standards from:

American Gear Manufacturers Association

1330 Massachusetts Avenue, N.W. . - . Washington, D. C. 20005 •

'

6.1. Summary of Standards . _

6.1.1 AGMA 295.03 (1968) SPECIFICATION FOR MEASUREMENT OF SOUND ON HIGH SPEED HELICAL

AND HERRINGBONE GEAR UNITS.

This Standard applies to gear units which are within the scope of Standard

AGMA 421.06, "Standard Practice for High Speed Helical and Herringbone Gear

Units", and as produced by the AGMA High Speed Units Manufacturer's Group. It does not include marine propulsion, aerospace, or automotive gearing. The

specifications and procedures apply to sound measurement, testing methods, and

limiting values of direct air-borne sound generated by a gear unit, and the

auxiliary equipment required for its operation, whose prime mover is not integral

with the unit.

Sound level characteristics of a gear unit are affected by types of

foundations and room surroundings. Therefore, it should be understood that shop

tests may not fully determine the level of sound in the installed locations.

6.1.2 AGMA 297.01 (1973) SOUND FOR ENCLOSED HELICAL, HERRINGBONE AND SPIRAL LEVEL GEAR

DRIVES.

The purpose of this standard is to present the instrumentation and procedure

to be used for sound measurements of enclosed helical, herringbone and spiral

bevel gear drives as well as to present typical maximum sound levels (A-weighted

sound pressure levels) . This standard is limited to enclosed speed reducing or increasing gear drives designed and rated in accordance with Standard AGMA 420.04,

"Practice for Enclosed Speed Reducers or Increasers Using Spur, Helical,

Herringbone and Spiral Bevel Gears" and is limited to gears operating at a maximum

pitch line -velocity of 5000 fpm and a maximum speed of 3600 rpm. This standard

includes the instrumentation and procedure necessary for the determination of the

gear unit sound level or octave-band sound pressure levels.

6.1.3 AGMA 298.01 (1975) SOUND FOR GEARMOTORS AND IN-LINE REDUCERS AND INCREASERS.

The purpose of this standard is to present the instrumentation and procedure

to be used for sound measurements of gearmotors and in-line reducers and

Increasers as well as to present typical maximum sound levels (A-weighted sound

pressure levels)

I

8
7 . American National Standards Institute (ANSI)

Purchase standards from: , • .

American National Standards Institute

1430 Broadway . i New York, NY 10018 , . -

7.1. Summary of Standards

7.1.1 ANSI SI. 1-1960 (R1971) AMERICAN NATIONAL STANDARD ACOUSTICAL TERMINOLOGY.

The purpose of this Standard is to establish standard acoustical terminology.

7.1.2 ANSI SI. 2-1962 (R1971) AMERICAN NATIONAL STANDARD METHOD FOR THE PHYSICAL

MEASUREMENT OF SOUND (PARTIALLY REVISED BY 81.13-1971 AND BY SI. 21-1972).

This Standard applies primarily to airborne sound produced by apparatus which

normally operates in air. These sounds must be nonimpulsive and of sufficient

duration to be within the dynamic measuring capabilities of the instruments used.

It applies primarily to apparatus which radiates sound as a by-product of its

primary function. However, the general principles apply also to other sources of

s ound

7.1.3 ANSI SI. 4-1971 AMERICAN NATIONAL SPECIFICATION FOR SOUND LEVEL METERS.

The sound level meter is intended to be equally sensitive to sounds arriving

at various angles, and to provide an accurate measurement of sound level with

certain weightings for sound within stated ranges and with an indicating

instrument that has standardized characteristics. The basic calibration of the

sound level meter is given in terms of a random-incidence acoustic field of known

properties

It is recognized that various degrees of precision and accuracy are required

in the practical measurement of sounds of various kinds for different purposes.

Hence, this Standard provides the minimum requirements for three basic types of

sound level meters: Types 1, 2, and 3, with performance requirements that become

progressively less stringent, preceeding from Type 1 to Type 3. Further, it is

recognized that sound level meters may be desired for special purposes that do not

require the complexity of any of the three basic types. Therefore, provision is

made for a special purpose sound level meter, Type S. The Type S meter can be

qualified to the performance of any of the basic types (1, 2, 3) but is not

required to have all three weighting networks.

7.1.4 ANSI SI. 5-1963 (R1971) AMERICAN NATIONAL STANDARD RECOMMENDED PRACTICES FOR

LOUD-SPEAKER MEASUREMENTS. (IEEE 219-1961).

These recommended practices, taken from the 1961 version of IEEE 219, define

terms associated with loudspeakers and their testing, recommend various methods of

testing, anc indicate preferred methods of presenting information regarding their

characteristics

7.1.5 ANSI SI. 6-1967 (R1971) AMERICAN NATIONAL STANDARD PREFERRED FREQUENCIES AND BAND

NUMBERS FOR ACOUSTICAL MEASUREMENTS. (Agrees with ISO 266-1975.)

For certain acoustical measurements a constant-frequency increment is a suitable spacing. More commonly, however, a constant-percentage increment is

adopted and the test frequencies then form a geometric series. This Standard

deals with the geometric series. The present Standard is not concerned with

frequencies for music.

9
7.1.6 ANSI SI. 7-1970 SOUND ABSORPTION OF ACOUSTICAL MATERIALS IN REVERBERATION ROOMS,

METHOD OF TEST FOR.

See ASTM C423-66.

7.1.7 ANSI SI. 8-1969 AMERICAN NATIONAL STANDARD PREFERRED REFERENCE QUANTITIES FOR

" ACOUSTICAL LEVELS.

This Standard is concerned with the reference quantities for, and definitions

of, some levels for acoustics, electroacoustics , and mechanical vibrations. It applies to oscillatory quantities. The use of levels is not made mandatory by

this Standard. It simply provides standard reference quantities for use when, and

if, levels are employed for reasons beyond the scope of the Standard. Reference

quantities are stated in units of the International System (Systeme International

SI), and also in centimeter-gram-second (cgs) and British units. The reference

quantities are, however, applicable regardless of the system of units employed.

Certain symbols and abbreviations not already standardized were needed, and

have been employed here simply for illustrative purposes. The present Standard is

intended to encourage uniformity of practice by specifying a definition for a level likely to be employed in acoustics. The purpose of this Standard is to provide a preferred reference quantity of convenient magnitude for a given kind of

acoustical level.

7.1.8 ANSI SI. 10-1966 (R1971) AMERICAN NATIONAL STANDARD METHODS FOR THE CALIBRATION OF

MICROPHONES.

In this Standard, methods are described for performing absolute and

comparison calibrations of laboratory standard microphones specified in American

Standard Specification for Laboratory Standard Pressure Microphones, Z24. 8-1949.

Absolute calibration is based upon the reciprocity principle. Techniques for

performing pressure (coupler), free-field, and random-field calibrations are described, including experimental procedures. The free-field and random-field

calibration techniques may also be used for calibrating microphones not described

in American Standard Z24. 8-1949.

(Note: Also see lEC 327 (1971)).

7.1.9 ANSI SI. 11-1966 (R1971) AMERICAN NATIONAL STANDARD SPECIFICATION FOR OCTAVE,

HALF-OCTAVE, AND THIRD-OCTAVE BAND FILTER SETS.

The purpose of this standard for filter sets is to specify particular

bandwidths and characteristics which may be used to ensure that all analyses of

noise will be consistent within known tolerances when made with similar filter

sets meeting these specifications. It is suited to the requirements for

analyzing, as a function of frequency, a broadband electrical signal. For

acoustical measurements an electro-acoustic-transducer and amplifier are employed

to convert the acoustic signal to be analyzed into the required electrical signal.

(Note: Also see lEC 225 (1966))

7.1.10 ANSI SI. 12-1967 (R1972) AMERICAN NATIONAL STANDARD SPECIFICATIONS FOR LABORATORY

STANDARD MICROPHONES.

This Standard describes types of laboratory microphones that are suitable for

calibration by an absolute method such as the reciprocity technique described in

U.S. Standard Method for the Calibration of Microphones, SI. 10- 1966. These

microphones are intended for use as acoustical measurement standards either in a free-field or in conjunction with a variety of devices such as artificial voices

and couplers for calibrating earphones or microphones.

10
7.1.11 ANSI SI. 13-1971 AMERICAN NATIONAL STANDARD METHODS FOR THE MEASUREMENT OF SOUND

PRESSURE LEVELS. (Partial revision of SI. 2-1962).

The purpose of this Standard is to provide uniform guidelines for measuring

and reporting sound-pressure levels observed under different environmental

conditions. This Standard is applicable to the many different types of

soimd-pressure levels observed under dif feren . environmental conditions. This

Standard is applicable to the many different types of sound-pressure-level

measurements commonly encountered in practice. This Standard is intended to assist in the preparation of test codes for (1) determining compliance with a specification, ordinance, or acoustical criterion, and (2) obtaining information

to assess the effects of noise on people or equipment.

7.1.12 ANSI SI. 21-1972 AMERICAN NATIONAL STANDARD METHODS FOR THE DETERMINATION OF SOUND

POWER LEVELS OF SMALL SOURCES IN REVERBERATION ROOMS. (Revision of Section 3.5 of

SI. 2-1962.)

This Standard describes a direct method and a comparison method for

determining the sound power level produced by a source. This Standard contains

test room requirements, source locations and operating conditions,

instrumentation, and techniques for obtaining an estimate of the mean-square sound

pressure from which the sound power level of the source in octave or one-third

octave bands is calculated. It is intended to provide techniques for acoustical

measurements that can be used in test codes for particular types of equipment.

This Standard applies primarily to the measurement of sound that is uniformly

distributed in frequency over the frequency range of interest and is relatively

steady for at least 30 sec. The spectrum of the sound may, however, also include

prominent discrete-frequency components or narrow bands.

7.1.13 ANSI S3. 1-1960 (R1971) AMERICAN NATIONAL STANDARD CRITERIA FOR BACKGROUND NOISE

IN AUDIOMETER ROOMS.

This Standard specifies the maximum ambient sound-pressure levels in an audiometer room that will produce negligible masking of tones presented at normal

threshold pressures specified in American National Standard Audiometers for

General Diagnostic Purposes, Z24. 5-1951, and American National Standard

Specification for Pure-Tone Audiometers for Screening Purposes, Z24. 12-1952.

This Standard pertains to earphone listening and pure-tone audiometry.

Cushions and earphones not described in American Standards Z24. 5-1951 and

Z24. 12-1952 are specifically excluded.

(Note: ANSI Z24. 5-1951 and ANSI Z24. 12-1952 have been replaced by ANSI

S3. 6-1969.)

7.1.14 ANSI S3. 2-1960 (R1971) AMERICAN NATIONAL STANDARD METHOD FOR MEASUREMENT OF

MONOSYLLABIC WORD INTELLIGIBILITY.

This Standard describes the procedures to be followed in conducting

intelligibility tests which employ monosyllabic word lists.

The purpose of this Standard is (1) to specify the speech material and the

methods to be used in these tests, and (2) to note the variables to be controlled

during the measurement and to be evaluated in the report.

7.1.15 ANSI S3. 3-1960 (R1971) AMERICAN NATIONAL STANDARD METHODS FOR MEASUREMENT OF

ELECTROACOUSTICAL CHARACTERISTICS OF HEARING AIDS.

The purpose of this Standard is to describe practicable and reproducible

methods of determining certain physical performance characteristics of

air-conduction hearing aids that use electronic amplification and acoustic

coupling to ear canal by means of ear inserts, e.g., ear molds or similar devices.

This Standard does not apply when automatic gain control is in use. The

11
acoustical test procedure is based on the free-field technique, in which the

hearing aid is placed in a plane progressive wave with the earphone coupled to a standardized coupler. The results obtained by the methods specified herein

express the performance under the conditions of the test, but will not necessarily

agree exactly with the performance of the hearing aid under practical conditions

, of use. For this reason, the difference between practical and test conditions

must be borne in mind in interpreting the test results.

(Note: Also see lEC 118 (1959).) : ,

'

,

'

7.1.16 ANSI S3. 4-1968 (R1972) AMERICAN NATIONAL STANDARD PROCEDURE FOR THE COMPUTATION

OF LOUDNESS OF NOISE.

This Standard specifies a procedure for calculating the loudness experienced

by a typical listener under the following conditions:

Diffuse Field. The sound is assumed to reach the listener's ears from

essentially all directions. This condition is approximated in an ordinary

room.

Spectrum. The procedure is designed specifically for noise with

broad-band spectra. Errors may arise if it is applied to noises with sharp

line spectral components, e.g., fan-blade noise.

Steady State. The procedure is designed for noises that are steady

state rather than intermittent. Application to certain types of intermittent

sounds, e.g., impact sounds and speech, may lead to discrepancies between

measured and calculated loudness levels. The magnitude of the discrepancy

will be related to the dynamic characteristics of the sound level meter used

to determine the sound-pressure levels.

7.1.17 ANSI S3. 5-1969 AMERICAN NATIONAL STANDARD METHODS FOR THE CALCULATION OF THE

ARTICULATION INDEX.

Methods have been developed for computing a physical measure that is highly

correlated with the intelligibility of speech as evaluated by speech preception

tests administered to a given group of talkers and listeners. This measure is

called the Articulation Index, AI. The AI is a weighted fraction representing,

for a given speech channel and noise condition, the effective proportion of the

normal speech signal that is available to a listener for conveying speech

intelligibility. AI is computed from acoustical measurements or estimates of the

speech spectrum and of the effective masking spectrum of any noise which may be

present along with the speech at the ear of a listener.

The method described in this Standard is designed for and has been

principally validated against intelligibility tests involving adult male talkers.

The method cannot, therefore, be assumed to apply to situations Involving female

talkers or children. The purpose of this Standard is to prescribe procedures for

computing an AI and to provide functions relating to AI and speech intelligibility

scores obtained with male talkers.

7.1.18 ANSI S3. 6-1969 AMERICAN NATIONAL STANDARD SPECIFICATIONS FOR AUDIOMETERS.

(Replaces ANSI Z24. 5-1951, Z24. 12-1952, and Z24 . 13-1953 .

The audiometers covered by 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, primarily for the purpose of

identification of hearing deficiencies of the individual.

7.1.19 ANSI S3. 7-1973 COUPLER CALIBRATION OF EARPHONES, METHOD FOR. (REVISION AND

REDESIGNATION OF Z24. 9-1949).

This standard specifies and describes earphone couplers that are in current

use, together with their capabilities and limitations, and presents methods for

the coupler calibration of earphones. Most of these methods are applicable to

12
precision point-by-point determination or to automatic data recording.

The purpose of coupler calibration of earphones is to provide a simple,

convenient, and reproducible means of determining their acoustical output. Each

of the couplers described in this standard has been designed for use with a specific class of earphone. When so used, the couplers have acoustic-input

impedances which, over a limited frequency range, are approximately equal to the

corresponding impedances of the average human ear under the specified conditions.

The couplers described in this standard are suitable for use with supra-aural

Cagainst-the-ear) and insert (ear-canal) type earphones.

7.1.20 ANSI S3. 8-1967 (R1971) . AMERICAN NATIONAL STANDARD METHOD OF EXPRESSING HEARING

AID PERFORMANCE.

The purpose of this Standard is to provide a uniform method of numerically

and graphically expressing certain fundamental performance characteristics of

hearing aids in a simple manner, so that those using such data can be assured of

their meaning.

All quantities to be specified in this Standard shall be based on measurements made in accordance with U. S. Standard Methods for Measurement of the

Electroacoustical Characteristics of Hearing Aids, S3. 3-1960.

7.1.21 ANSI S3. 13-1972. AMERICAN NATIONAL STANDARD ARTIFICIAL HEAD-BONE FOR THE

CALIBRATION OF AUDIOMETER BONE VIBRATORSThe purpose of this Standard is to specify the mechanical impedance

characteristic of an artificial headbone that would be incorporated into devices

used in calibrating audiometer bone vibrators. The Standard also specifies the

vibrator tip size and shape, as well as the static force of application for which

the standardized mechanical impedance characteristics apply. The characteristics

of an interim head-bone device presently used for audiometer bone-vibrator

calibration are stated in Appendix A and corresponding interim reference threshold

levels are given.

7.1.22 ANSI S3. 17-1975 METHOD FOR RATING THE SOUND POWER SPECTRA OF SMALL STATIONARY

NOISE SOURCES.

See ASA STD 4-1975.

, 7.1.23 ANSI S3. 19-1974 MEASUREMENT OF REAL-EAR PROTECTION OF HEARING PROTECTORS AND

PHYSICAL ATTENUATION OF EARMUFFS, METHOD FOR THE (REVISION AND REDESIGNATION OF

Z24. 22-1957) (ASA STD 1-1975).

This standard specifies the definitions, requirements, and procedures for the

measurement of acoustical performance of personal hearing protection devices. It

is a revision of American National Standard for the Measurement of the Real-Ear

Attenuation of Ear Protectors at Thresholds, Z24. 22-1957. The principal changes

are the inclusion of a method for the measurement of physical attenuation of , earmuff devices and the substitution of narrow bands of noise instead of discrete

tones as the test stimuli. The physical measurement method is intended for

production test and engineering design; it is not suitable for earplug testing.

This standard is not appropriate to the evaluation of hearing-protective devices

to operate exclusively against impulsive noise.

7.1.24 Al^SI S3. 20-19 73 PSYCHOACOUSTICAL TERMINOLOGY.

This standard gives definitions of psychoacoustical terms.

7.1.25 ANSI S5. 1-1971 MEASUREMENT OF SOUND FROM PNEUMATIC EQUIPMENT, TEST CODE FOR THE.

See Compressed Air and Gas Institute (CAGI) Test Code.

13
7.1.26 ANSI S6. 1-1973 QUALIFYING A SOUND DATA ACQUISITION SYSTEM.

See SAE J184-1973.

7.1.27 ANSI S6. 2-197 3 EXTERIOR SOUND LEVEL FOR SNOWMOBILES.

See SAE J192a-1973. '

7.1.28 ANSI S6. 3-1973 SOUND LEVEL FOR PASSENGER CARS AND LIGHT TRUCKS.

See SAE J986a-1972.

7.1.29 ANSI S6. 4-1973 COMPUTING THE EFFECTIVE PERCEIVED NOISE LEVEL FOR FLYOVER AIRCRAFT

NOISE, DEFINITIONS AND PROCEDURES FOR.

See SAE ARP 1071-1973.

7.1.30 ANSI YIO. 11-1953. AMERICAN NATIONAL STANDARD LETTER SYMBOLS FOR ACOUSTICS.

This Standard comprises letter symbols for use in acoustics.

7.1.31 ANSI Y32. 18-1972. AMERICAN NATIONAL STANDARD SYMBOLS FOR MECHANICAL AND

ACOUSTICAL ELEMENTS AS USED IN SCHEMATIC DIAGRAMS.

This document presents standard symbols and definitions that may be used in

constructing schematic diagrams for mechanical and acoustical systems whose

performances are describable by finite sets of scalar variables.

7.2. Draft Proposals for New Standards

7.2.1 ANSI SI. 22 SCALES AND RATIOS FOR PLOTTING.

7.2.2 ANSI S1.23-197X METHOD FOR DESIGNATING THE SOUND POWER EMITTED BY MACHINERY AND

EQUIPMENT

7.2.3 REVISION OF ANSI S3. 3-1960 (R1971) AND ANSI S3. 8-1967 (R1971) INTO A SINGLE

STANDARD, MEASUREMENT AND EXPRESSION OF HEARING AID PERFORMANCE.

7.2.4 SUPPLEMENT OR ADDENDUM TO ANSI S3. 7-1973 ON CALIBRATION OF HEARING AID RECEIVERS

ON A MODIFIED ZWISLOCKI-TYPE COUPLER.

7.2.5 ANSI S3. 14 SPEECH INTERFERENCE.

7.2.6 ANSI S3. 15 METHOD FOR MEASUREMENT OF COMMUNITY NOISE.

7.2.7 ANSI S3. 16 HEARING CONSERVATION CRITERIA.

7.2.8 ANSI S3. 21 PURE-TONE AUDIOMETRY.

7.2.9 ANSI S3. 22 SPECIFICATION OF HEARING AID CHARACTERISTICS.

7.2.10 ANSI SlO.l THE MEASUREMENT OF SOUND EMITTED BY PORTABLE, STATIONARY AND FIXED

ELECTRIC TOOLS.

7.2.11 ABSORPTION OF ANY SOUND BY THE ATMOSPHERE.

7.2.12 EVALUATION OF ABSORPTIVE WEDGES AND ANECHOIC CHAMBERS.

14
8. American Society of Heating, Refrigerating, and Air-Conditioning

Engineers (ASHRAE)

Purchase standards from:

American Society of Heating, Refrigerating, and

Air Conditioning Engineers

345 E. 47th Street

New York, NY 10017

8 .1 Summary of Standards

8.1.1 ASHRAE 36-72 METHODS OF TESTING FOR SOUND RATING HEATING, REFRIGERATING, AND

AIR-CONDITIONING EQUIPMENT (SUPERCEDES ASHRAE STANDARDS 36-62, 36A-63, and

36B-63)

This Standard establishes a method of testing heating, refrigerating and

air-conditioning equipment to determine the sound power levels in frequency bands

It applies to heating, refrigerating and air-conditioning equipment, or portions

of such equipment, that radiate sound directly either to a room or to the

outdoors

This test procedure determines in standardized frequency bands the sound

power level output of mechanical equipment by a comparison between: (a) the

space/ time-averaged sound pressure established by the operation of the equipment

in a suitably designed test room; and (b) the space/ time-averaged sound pressure

established in the same room by a stable reference sound source whose sound power

output has been accurately calibrated independently. (This procedure is commonly

called the "comparison method".)

8.1.2 ASHRAE 68-75 METHOD OF TESTING SOUT^D POWER RADIATED INTO DUCTS FROM AIR MOVING

DEVICES. . . . ,

,

. .....

This Standard describes a laboratory method of determining the sound power

transmitted into ducts from air moving devices.

15
9 . American Society for Testing and Materials (ASTM)

Purchase standards from:

American Society for Testing and Materials

1916 Race Street

Philadelphia, PA 19103

9.1. Summary of Standards

9.1.1 ASTM C384-58 (Reapproved 1972) STANDARD METHOD OF TEST FOR IMPEDANCE AND

ABSORPTION OF ACOUSTICAL MATERIALS BY THE TUBE METHOD.

This method of test is limited to the use of apparatus consisting of a tube

of uniform cross-section and fixed length, terminated by a specimen of acoustical

material, excited by a single tone of selectable frequency, in which the standing

wave pattern in front of the specimen upon which plane waves impinge at normal

incidence in explored by means of a moving probe tube or microphone. This tube

method provides absolute measurement of the normal incidence sound absorption

coefficient and the specific normal acoustic impedance of a material. Normal

incidence coefficients, as measured by this method, are considerably lower than

random incidence values, which more closely represent the performance of the

material in a room; and there is no simple, unique relation between the two values. Means of estimating random incidence values from the measured normal

incidence data are given in Appendix I.

9.1.2 ASTM C423-66 (Reapproved 1972) STANDARD METHOD OF TEST FOR SOUND ABSORPTION OF

ACOUSTICAL MATERIALS IN REVERBERATION ROOMS (ANSI SI. 7-1970).

This method covers the measurement of the sound absorption of acoustical

materials in a diffuse sound field. When a material is in the form of an extended

plane surface, such as an acoustical ceiling or wall treatment, the results shall

be given as sound absorption coefficients. When the materials are separate

objects, such as theater chairs or unit sound absorbers, the results shall be

given in sabins per unit with a description of the number and spacing of the

units

9.1.3 ASTM C6 34-73 STANDARD DEFINITIONS OF TERMS RELATING TO ACOUSTICAL TESTS OF

BUILDING CONSTRUCTIONS AND MATERIALS.

This Standard lists the terms commonly associated with the acoustical tests

of buildings. In some of the entries, those that are measures of physical

quantities, the associated symbol dimensions and units are given.

9.1.4 ASTM C643-73 PAINTING CEILING MATERIALS FOR ACOUSTICAL ABSORPTION TESTS.

This method covers the painting of an acoustical ceiling material to determine the changes, if any, in its sound absorption coefficients when

repainting is done for maintenance reasons. The specimen size and the procedure

for the acoustical tests shall be as required by ASTM C423.

9.1.5 ASTM E90-75 STANDARD RECOMMENDED PRACTICE FOR LABORATORY MEASUREMENT OF AIRBORNE

SOUND TRANSMISSION LOSS OF BUILDING PARTITIONS.

This Recommended Practice covers the laboratory measurement of airborne

sound transmission loss of building partitions such as walls of all kinds,

floor-ceiling assemblies, doors, and other space-dividing elements. The sound

transmission loss is defined in terms of a diffuse incident sound field, and this

is intrinsic to the test procedure. The results are most directly applicable to similar sound fields, but provide a useful general measure of performance of the

variety of sound fields to which a partition may typically be exposed.

16
9.1.6 ASTM E336-71 STANDARD RECOMMENDED PRACTICE FOR MEASUREMENT OF AIRBORNE SOUND

INSULATION IN BUILDINGS.

This Recommended Practice establishes uniform procedures for the

determination of field transmission loss, that is, the airborne sound insulation

provided by a partition already installed in a building. It also establishes, in

Appendix Al, a standard method for the measurement of the noise reduction between

two rooms in a building, that is, the difference in average sound pressure levels

in the rooms on opposite sides of the test partition. Where the test structure is

a complete enclosure out-of-doors, neither the field transmission loss nor the

noise reduction is appropriate; instead, a method is established for determining

the insertion loss, also in Appendix Al . This Recommended Practice gives

measurement procedures for determining the field transmission loss in nearly all

cases that may be encountered in the field; no limitation to room-to-room

transmission is intended. Thus, several different test procedures are given, each

suited to a specific type of measurement situation; the appropriate measurement

procedure must be selected for each field test according to the type of situation

which that particular case most closely resembles.

9.1.7 ASTM E413-73 STANDARD CLASSIFICATION FOR DETERMINATION OF SOUND TRANSMISSION

CLASS.

The purpose of this Classification is to provide a single-figure rating that can be used for comparing partitions for general building design purposes. The

rating is designed to correlate with subjective impressions of the sound

insulation provided against the sounds of speech, radio, television, music and

similar sources of noise in offices and dwellings. Excluded from the scope of

this classification system are applications involving noise spectra that differ

markedly from those described above. Thus excluded, for example, would be the

noises produced by most machinery, certain industrial processes, bowling alleys,

power transformers, and the like. A particular exclusion would be the exterior

walls of buildings, for which noise problems are most likely to involve motor

vehicles or aircraft. In all such problems it is best to use the detailed sound

transmission loss values, in conjunction with actual spectra of intrusive and

ambient noise.

9.1.8 ASTM E4 77-73 STANDARD METHOD OF TESTING DUCT LINER MATERIALS AND PREFABRICATED

SILENCERS FOR ACOUSTICAL AND AIRFLOW PERFORMANCE.

This Method covers the laboratory testing of duct liner materials, integral

ducts, and in-duct absorptive silencers used in the ventilation systems of

buildings. Procedures are described for the measurement of acoustical insertion

loss, airflow generated noise, and pressure drop as a function of airflow.

Excluded from the scope are reactive mufflers and those designed for uses other

than in ventilation systems, such as automobile mufflers.

9.1.9 ASTM E492-73T TENATIVE METHOD OF LABORATORY MEASUREMENT OF IMPACT SOUND

TRANSMISSION THROUGH FLOOR CEILING ASSEMBLIES USING THE TAPPING MACHINE (1971).

This Method covers a laboratory method of measuring impact sound transmission

of floor-ceiling assemblies, wherein it is assumed that the test specimen

constitutes the primary sound transmission path into a receiving room located

directly below and in which there exists a diffuse sound field. Measurements may

be conducted on floor-ceiling assemblies of all kinds, including those with

floating-floor or suspended ceiling elements, or both, and floor-ceiling

assemblies surfaced with any type of floor-surfacing or floor-covering materials.

This method further prescribes a uniform method of reporting laboratory test data,

and a single-figure classification rating, "Impact Insulation Class, IIC" that can be used by architects, builders, and specification and code authorities for

acoustical design purposes in building construction.

17
9.1.10 ASTM E497-73T TENATIVE RECOMMENDED PRACTICE FOR INSTALLATION OF FIXED PARTITIONS

OF LIGHT FRiVME TYPE FOR THE PURPOSE OF CONSERVING THEIR SOUND INSULATION

EFFICIENCY.

This Recommended Practice covers measures intended to prevent situations or conditions that will detract from the sound- insulating properties of

acoustically- rated walls of the light frame type. It is not intended to include

all sound insulating constructions. Many acoustically-rated partitions are also

fire rated and when being installed must be built in accordance with the

construction details specified in the fire test construction. In any event,

applicable building codes and regulations should be checked for possible

conflicts

Fixed partitions of light frame type are interior (load bearing or non-lo|d

bear ing) 2walls of wood or metal frame construction weighing less than 20 lb/ft

(98 kg/m ) when assembled, exclusive of doors and windows. They are designed to remain in place for the normal lifespan of the building. Fixed partitions of

light frame type do not include those of cast concrete, precast concrete, concrete

masonry blocks, gypsum blocks, clay tile blocks, or other similar heavy

construction.

Excluded from this scope are operable and demountable partitions. Operable

are those partitions which are instantly movable. Demountable partitions are

those which are designed and installed with the intent of later being taken down

and re-erected by a crew over a period of time, with the components being

reusable. Plumbing wall and kitchen problems are excluded from this document.

9.1.11 ASTM E557-75 STANDARD RECOMMENDED PRACTICE FOR THE ARCHITECTURAL APPLICATION AND

INSTALLATION OF OPERABLE PARTITIONS.

This Standard describes practices to be followed in preparation for

application and installation of operable partitions and, to some extent, in the

design of the building in which they are installed.

9.2. Draft Proposals for New Standards

9.2.1 FIELD SOUND ISOLATION TEST.

9.2.2 METHOD FOR LABORATORY MEASUREMENT OF THE NOISE REDUCTION OF SOUND ISOLATING

ENCLOSURES

9.2.3 METHOD OF TEST FOR SOUND REFLECTION OF OPEN-PLAN CEILING ASSEMBLIES.

9.2.4 METHOD OF TEST FOR AIRBORNE SOUND INSULATION BETWEEN ROOMS SHARiNG A COMMON

CEILING AND PLENUM.

9.2.5 ALTERNATE IMPACT TEST METHOD USING A MODIFIED TAPPING MACHINE.

18
10 . American Textile Machinery Association (ATMA)

Purchase standards from:

American Textile Machinery Association

1730 M St. N.W. Washington, D. C. 20036

10.1 Summary of Standards

10.1.1 ATMA TEST PROCEDURE (1973) NOISE MEASUREMENT TECHNIQUE FOR TEXTILE MACHINERY.

This Noise Measurement Technique is designed for application to textile

machinery as defined in the procedure, except where other recognized industry

standards have been issued prior to issuance of this Technique.

The purpose of this Technique is to provide a uniform basis for measuring and

communicating machinery noise information between textile machinery manufacturers

and textile manufacturers.

19
11 . Anti-Friction Bearing Manufacturers Association (AFBMA)

Purchase standards from: ,;< '

Anti-Friction Bearing Manufacturers Association .

_ 60 East 42nd Street . .. ,'.

New York, NY 10017

11.1 Summary of Standards

11.1.1 AFBMA STANDARD NO. 13 (1968) ROLLING BEARING VIBRATION AND NOISE.

Under certain operating conditions, vibration in rotating rolling bearings

can be of importance as an operating characteristic of such bearings. For this

reason, the measurement of vibration emitted by a rolling bearing under specified

test conditions is utilized for study and qualification as one facet of quality assurance

This standard on rolling bearing noise and vibration serves to define and

specify, for purposes of bearing quality assurance, the physical quantities

measured and the test conditions utilized in measurement of vibration and noise

generated by rolling bearings. Based on the standard, parties to the acceptance

inspection of rolling bearings may, by agreement, establish acceptance specifications and grades of rolling bearings with which to control bearing vibration and

noise

In the current edition of this Standard, only selected methods for the

measurement of the (structure-borne) vibration of certain types of ball bearings

have been specified. Other vibration measurement methods, as well as methods for

the measurement of rolling bearing (air-borne) noise, may be specified in later

editions

20
12 . Association of Home Appliance Manufacturers (AHAM)

Purchase standards from:

Association of Home Appliance Manufacturers

20 North Wacker Drive

Chicago, IL 60606

12.1 Summary of Standards

12.1.1 AHAM RAC-2SR (1971) ROOM AIR CONDITIONER SOUND RATING.

The standard establishes uniform testing conditions. The sound rating of room air conditioners shall be based upon tests made in accordance with ASHRAE

Standards 36A-63, Method of Determining Sound Power Levels of Room Air

Conditioners and Other Ductless, Through- the-Wall Equipment in test rooms qualified for pure tone response in accordance with Appendix I of this Standard in

the one-third octave bands having center frequencies from 100 thru 10,000 Hz,

inclusive. Temperature conditions, electrical input, and position of dampers,

grilles, and controls shall be maintained continuously for a minimum of one hour

before sound measurements are taken to ensure that a stabilized condition has been

reached

(Note: ASHRAE Standard 36A-63 has since been superceded by ASHRAE Standard 36-72,

Methods of Testing for Sound Rating Heating, Refrigerating, and Air-Conditioning

Equipment .

12.2. Draft Proposals for New Standards

12.2.1 ROOM AIR CONDITIONER SOUND APPLICATION STANDARD.

21
13 . Compressed Air and Gas Institute (CAGI)

Purchase standards from: . /ftbn--:

Compressed Air and Gas Institute . ,; 2130 Keith Building

Cleveland, OH 44115

"

13.1. Summary of Standards

13.1.1 CAGI TEST CODE (1969) CAGI-PNEUROP TEST CODE FOR THE MEASUREMENT OF SOUND FROM

PNEUMATIC EQUIPMENT (ANSI S5. 1-1971). :

The purpose of the Code is to provide standard test procedures for the

measurement of airborne sound from pneimiatic equipment. This code applies to compressors and pneumatic equipment and specifies procedures and operating

conditions acceptable and expedient for use by non-specialists as well as by

acoustical engineers.

22
14 . Diesel Engine Manufacturers Association (DEMA)

Purchase standards from: '

Diesel Engine Manufacturers Association

2130 Keith Building

Cleveland, OH 44115

14.1. Summary of Standards

14.1.1 DEMA TEST CODE (1972) FOR THE MEASUREMENT OF SOUND FROM HEAVY-DUTY RECIPROCATING

ENGINES

The purpose of this document is to establish a standard procedure for

measuring, recording, and reporting data in acoustic surveys at engine

installations. Section 5.0 deals with noise levels inside the building. Section

6.0 deals with noise levels outside the building, particularly on plant

boundaries

This Code applies to heavy-duty internal combustion engines and driven

equipment, such as generators, pumps or compressors and specifies procedures and

operating conditions acceptable and expedient for use by non-specialists as well

as by acoustic engineers.

23
15 . Electronic Industries Association (EIA)

Purchase standards from:

[5 rj ,^

Electronic Industries Association .....

2001 Eye Street, N.W. Washington, D. C. 20006 .

'

"

15.1. Summary of Standards ' "

•'•

'

15.1.1 EIA RS-426 (1975) LOUDSPEAKERS, POWER RATING, SINGLE VOICE COIL.

This test measures the loudspeaker's ability to provide long service with

rated maximum input power. This test may be used as a life test. Two causes of

failure are: thermal, due to overheating the voice coil, and mechanical, due to fatigue of some part. "Program Noise" approximates normal program material for

these tests.

24
16. Federal Construction Guide Specification (FCGS)

Purchase standards from:

General Services Administration .' Public Building Service

Office of Construction Management

Criteria and Research Branch

19th and F Street, N.W. Washington, D.C. 20405 .'

'

'

16.1. Summary of Standards

16.1.1 FCGS 09500 (1972) ACOUSTICAL TREATMENT. /

' '

This specification gives general guidelines for the preparation and/or

use of construction specifications by federal agencies. Its use is voluntary.

16.1.2 FCGS 15140 (1972) VIBRATION ISOLATION AND SOUND CRITERIA FOR EQUIPMENT.

See PBS: 4-1515-71.

25
17 . Federal Specifications

Purchase standards from:

Specification Sales (3FRDS) .... , . Building 197, Washington Navy Yard . i - General Services Administration

Washington, D.C. 20407

also at other General Services Administration . , , Business Service Centers

17.1. Summary of Standards

17.1.1 SS-S-llla AND AMENDMENT-1 (1968) SOUND CONTROLLING MATERIALS (TROWEL AND SPRAY

APPLICATIONS)

This specification covers acoustical materials for trowel or spray

application

17.1.2 SS-S-118a (3) (1972) SOUND CONTROLLING BLOCKS AND BOARDS (ACOUSTICAL TILES AND

PANELS, PREFABRICATED).

This specification covers prefabricated acoustical tiles and panels (blocks

and boards) which provide acoustical treatment and interior finish.

17.1.3 FEDERAL SPECIFICATION HH-I-5A5B INSULATION, THERMAL AND ACOUSTICAL (MINERAL

FIBER, DUCT LINING MATERIAL) (1971).

This specification covers mineral fiber insulation for lining the interior

surfaces of ducts, plenums, and other airhandling equipment, and to provide sound

attenuation in systems that handle air up to 250°F.

26
18 o Home Ventilating Institute (HVI)

Purchase standards from:

Home Ventilating Institute

230 North Michigan Ave.

Chicago, IL 60601

18.1. Summary of Standards

18.1.1 HVI SOUND TEST PROCEDURE (1974).

The general purpose of the HVI Report is to provide a laboratory procedure

for the taking of measurements of the sound output of home ventilating equipment

and to establish a method for the interpretation and/or presentation of the data

obtained

27
19 . Industrial Silencer Manufacturers Association (ISMA)

Purchase standards from:

R. J. Yeager, ISMA

c/o Burgess Industries

P. 0. Box 47146

Dallas, TX 75247

19.1. Summary of Standards

19.1.1 ISMA TEST PROCEDURE (1974). STANDARD LABORATORY TEST PROCEDURE FOR INSERTION LOSS

MEASUREMENT OF INTAKE AND EXHAUST SILENCERS FOR RECIPROCATING ENGINES.

This procedure covers dynamic insertion loss measurement under controlled

laboratory conditions on reciprocating engine intake and exhaust silencers.

Silencer pressure drop test procedure is covered by reference only. Standard

methods of interpolation and extrapolation of test data to cover other size

silencers is included.

19.1.2 ISMA TEST PROCEDURE (1974). FIELD TEST PROCEDURE FOR THE MEASUREMENT OF SILENCED

SOUND LEAKS AND/OR UNSILENCED SOUND LEVELS AND INSERTION LOSS, OF RECIPROCATING

ENGINE INTAKE AND EXHAUST SYSTEMS.

This procedure covers dynamic silenced, unsilenced and insertion loss

measurements of reciprocating engine intake and exhaust systems in the field. All

tests will be run with the engine at full load unless specifications covering the

silencer acoustical performance prescribe other operating conditions.

19.2. Draft Proposals for New Standards

19.2.1 INSERTION LOSS OF SILENCERS FOR POSITIVE DISPLACEMENT COMPRESSORS AND BLOWERS.

19.2.2 INSERTION LOSS OF SILENCERS FOR CENTRIFUGAL COMPRESSORS AND BLOWERS.

19.2.3 INSERTION LOSS OF VENT SILENCERS.

19.2.4 INSERTION LOSS OF PRESSURE REDUCTION AND REGULATOR VALVE SILENCERS.

19.2.5 INDUSTRIAL SILENCER RATING TECHNIQUES FOR NOISE.

28
20 . Institute of Electrical and Electronic Engineers (IEEE)

Purchase standards from: , . ,

Institute of Electrical and Electronic Engineers ' 445 Hoes Lane

Piscataway, NJ 08854 ,-

20.1. Summary of Standards

20.1.1 IEEE STD. 85-1973 IEEE TEST PROCEDURE FOR AIRBORNE SOUND MEASUREMENTS ON ROTATING

ELECTRIC MACHINERY.

This test procedure defines approved methods for conducting tests and

reporting results to effect the uniform determination of rotating electric machine

sound under steady-state conditions with an accuracy of +3 dB tested in free

field, reverberant field, and semi-reverberant field acoustical environments.

This procedure assumes the presence of pure tones or the predominance of discrete

frequencies in the sound spectrum.

20.1.2 IEEE STD 219-1975 RECOMMENDED PRACTICES ON AUDIO AND ELECTROACOUSTICS : .; LOUDSPEAKER MEASUREMENTS. 1

These Recommended Practices define terms associated with loudspeakers and

their testing, recommend various methods of testing, and indicate preferred

methods of presenting information regarding their characteristics.

While the physical data which can be obtained are a helpful guide in

designing and in selecting a loudspeaker for a certain purpose, they are not a complete guarantee that the subjective performance will be satisfactory. Wherever

it is possible, the quality of reproduction should be checked by means of

listening tests. , i .

(Note: Also see ANSI SI. 5-1963 (R1971)). -

. ,

20.1.3 IEEE STD 258-1965 TEST PROCEDURE FOR CLOSE-TALKING PRESSURE-TYPE MICROPHONES. . ,

This document describes a practical and reproducible method of evaluating the

performance characteristics of a close-talking microphone by means of quantitative

measurements of the microphone characteristics using a standard artificial voice.

Terms associated with microphones and their testing are defined. Test procedure,

methods of presentation of data, and a standard artificial voice are specified.

The tests described in this document involve physical, steady-state measurements

only. The data obtained should be sufficient to enable an evaluation of quality

and performance of a given microphone in a speech communication system. However,

since it is sometimes desirable to obtain a subjective evaluation of a microphone,

a procedure for a qualitative performance test is described in Appendix I.

Several sections of the document specify experimental limits to account for

the effect of the test procedures on the accuracy of the data. These limits have

been chosen so that results within the range of normal engineering accuracy will

be obtained.

20.1.4 IEEE STD 297-1969 IEEE RECOMMENDED PRACTICE FOR SPEECH QUALITY MEASUREMENTS.

The IEEE Subcommittee on Subjective Measurements, charged with writing an engineering practice for the measurement of speech quality, concluded that a single method should not now be recommended. This Recommended Practice is

concerned only with preference measurements for which three methods are tentatively outlined. These are the Isopref erence Method, the Relative Preference

Method, and the Category-Judgment Method.

29
21 . Instrument Society of America CISA)

Purchase standards from:

Instrument Society of America

400 Stanwix Street

Pittsburgh, PA 15222

21.1. Summary of Standards

21.1.1 ISA-S37.10 (1969) SPECIFICATIONS AND TESTS FOR PIEZOELECTRIC PRESSURE AND

SOUND-PRESSURE TRANSDUCERS.

Included in this standard are uniform minimum general specifications for

describing design and performance characteristics and selected uniform acceptance

and qualification test methods, including calibration techniques for piezoelectric

transducers for sound pressure levels in excess of 100 dB overall re 20 yPa.

30
22 . International Conference of Building Officials (ICBO)

Purchase standards from:

International Conference of Building Officials

5 360 South Workman Mill Road

Whittier, CA 90601

22.1. Summary of Standards

22.1.1 UBC 35-1 LABORATORY DETERMINATION OF AIRBORNE SOUND TRANSMISSION CLASS (STC)

This Standard covers the laboratory measurement of airborne sound

transmission loss of building partitions such as walls, floor-ceiling assemblies,

doors, and other space-dividing elements.

This Standard also includes a system for establishing a sound transmission

class (STC) as a single-figure rating. The rating is designed to correlate with

subjective impressions of the sound insulation provided against the sounds of

speech, radio, television, music, and similar sources of noise in dwellings.

(Based on Standard Recommended Specifications E90-70, E413-70T, E90-61T of the

American Society for Testing and Materials.)

22.1.2 UBC 35-2 IMPACT SOUND INSULATION.

This Standard covers laboratory and field measurement of impact sound

transmission through floor-ceiling assemblies and establishes a method of

determining an Impact Insulation Class (IIC) as a single-figure rating. The

impact sound transmission performance of floor-ceiling assemblies regulated by

this Standard is based on measurements of absolute sound pressure levels produced

in a room directly below the test floor on which a "standard" tapping machine is

operated

(Based on U. S. Department of Housing and Urban Development Publication FT/TS-24,

Guide to Noise Control in Multifamily Dwellings.)

22.1.3 UBC-35-3 AIRBORNE SOUND INSULATION FIELD TEST.

This Standard establishes procedures for the determination of the extent of

airborne sound insulation provided by partitions (walls, ceiling, floors and

floor-ceiling assemblies) in existing buildings. This standard with UBC 35-1 also

establishes a procedure to determine the Sound Transmission Class for field tested

assemblies (FSTC or NIC).

(Based on Recommended Practice E336-67T of the American Society for Testing and

Materials .

31
23. International Electrotechnical Coininission (lEC)

Purchase standards from:

American National Standards Institute

1430 Broadway

New York, NY 10018

23.1. Summary of Standards

23.1.1. lEC 34-9 (1972) ROTATING ELECTRICAL MACHINES, PART 9 NOISE LIMITS.

This lEC recommendation represents the first step in setting international

limits for rotating electrical machine noise. The need for simplicity is

recognized and values for A-weighted sound levels have been adopted. When the

machine being tested emits one or more pure tones of significant intensity, the

A-weighted level is not sufficient and the recommendation provides for the use of

frequency band analysis in such cases. The limits listed are applicable to machines on no-load.

This recommendation covers rotating electrical machines (motors, generators,

convertors , etc.) for general application where the electromagnetic design has not

been limited to obtain a reduced noise level. It applies to machines in the

following power and speed ranges: IkW to 400 kW and 600 rev/min to 3750 rev/min.

23.1.2. lEC 50(08) (1960) INTERNATIONAL ELECTROTECHNICAL VOCABULARY, ELECTRO-ACOUSTICS.

The purpose of this Recommendation is to list definitions that have been

drawn up with the object of striking a correct balance between absolute precision

and simplicity.

23.1.3. lEC 118 (1959) RECOMMENDED METHODS FOR MEASUREMENTS OF THE ELECTRO-ACOUSTICAL

CHARACTERISTICS OF HEARING AIDS.

The purpose of these recommendations is to describe practicable and

reproducible methods of determining certain physical performance characteristics

of air-conduction hearing aids that use electronic amplification and are acoustically coupled to the eardrum by means of ear inserts; e.g., ear moulds or similar devices. The acoustic test procedure is based on the free field technique,

in which the hearing aid is placed in a plane progressive wave, with the earphone

coupled to a standardized coupler. Unless otherwise specified all measurements

are carried out without using an ear insert (ear mould) which is normally to be

regarded as incorporated in the coupler or the artificial ear employed. The

results obtained by the methods specified express the performance under the

conditions of the test, but will not necessarily agree exactly with the

performance of the hearing aid under practical conditions of use. For this

reason, the difference between practical and test conditions must be borne in mind

in interpreting the test results.

(Note: Also see ANSI S3. 3-1960 (R1971).)

23.1.4. lEC 118 AMENDMENT 1 (1973) RECOMMENDED METHODS FOR MEASUREMENTS OF THE

ELECTRO-ACOUSTICAL CHARACTERISTICS OF HEARING AIDS.

This lEC amm^ndment gives procedures for measurement of the sound pressure

level of the 2-cm coupler described in lEC 126(1973). It gives procedures for

the connection of the hearing aid for test as well as figures showing coupling

configurations for three types of earphones or hearing aids — the insert

earphone, the behind-the-ear type of hearing aid, and the in-the-ear type of

hearing aid.

32
23.1.5. lEC 123 (1961) RECOMMENDATIONS FOR SOUND LEVEL METERS.

The object of the present Recommendation is to specify the characteristics of

equipment to measure certain weighted sound pressure levels. The weighting

applied to each sinusoidal component of the sound pressure is given as a function

of frequency by three standard reference curves, called. A, B, and C.

In practice, measurements may have to be made under very different

conditions, ranging from the free field of a single source to a completely diffuse

field. In order to simplify the procedure for the calibration and checking of the

apparatus, these recommendations are written primarily in terms of the free field

response

23.1.6. lEC 126 (1973) lEC REFERENCE COUPLER FOR THE MEASUREMENT OF HEARING AIDS USING

EARPHONES COUPLED TO THE EAR BY MEANS OF EAR INSERTS.

The purpose of this Recommendation is to describe a coupler for loading the

earphone with a specified acoustic impedance when determining the physical

performance characteristics, in the frequency range 200 to 5000 Hz, of

air-conduction hearing aids using earphones coupled to the ear by means of ear inserts, e.g., ear moulds for similar devices. The use of this coupler does not

allow the actual performance of a hearing aid on a person to be obtained; however,

the lEC recommends its use as a simple and ready means for the exchange of

specifications and of physical data on hearing aids.

23.1.7. lEC 177 (1965) PURE TONE AUDIOMETERS FOR GENERAL DIAGNOSTIC PURPOSES.

The audiometer covered by this Recommendation is a device using pure tones

designed for general diagnostic use and for determining the hearing threshold

levels of individuals by (a) monaural air-conduction earphone listening, and by

(b) bone conduction. The Recommendation does not purport to deal with all the

features of audiometers, but specifies certain minimum requirements for a pure

tone audiometer for general diagnostic use.

The purpose of this Recommendation is to ensure that tests of the threshold

of hearing of a given individual on different audiometers, complying with the

Recommendation, will give substantially the same results under comparable

conditions and that the results obtained will present a good comparison between

the threshold of hearing of the individual and the standard reference threshold of

hearing. This Recommendation applies primarily to audiometers giving discrete

frequencies, but also applies to audiometers giving continuous frequency

variation, as far as the provisions are relevant.

23.1.8. lEC 178 (1965) PURE TONE SCREENING AUDIOMETERS.' ' '

The audiometer covered by this Recommendation is a device designed for

screening purposes by monaural air-conduction earphone listening using pure tones.

The Recommendation is almost identical to lEC Publication 177 in its

specifications for air-conduction. Notable differences are (a) the range of

frequencies and the range of sound pressure levels are smaller, and (b) the

tolerances for the accuracies of the sound pressure levels are larger.

23.1.9. lEC 179 (1973) PRECISION SOUND LEVEL METERS.

This Recommendation applies to sound level meters for high precision

apparatus for laboratory use, or for accurate measurements in which stable, high

fidelity and high quality apparatus are required. This Recommendation does not

apply to apparatus for 'measuring discontinuous sounds or sounds of very short

duration.

33
23.1.10. lEC 179A (1973) FIRST SUPPLEMENT TO PUBLICATION 179 (1973) PRECISION

SOUND LEVEL METERS, ADDITIONAL CHARACTERISTICS FOR THE MEASUREMENT OF

IMPULSIVE SOUNDS.

This lEC recommendation specifies the characteristics of an apparatus for

measuring sounds including sounds of short duration, single impulses and

sequences of impulses (pulses)

The apparatus specified in this recommendation complies with the

requirements for the precision sound level meter described in lEC Publication

179 and, in addition, is suitable for measuring impulsive sounds when the

purpose is to obtain a value representative of the approximate loudness.

23.1.11. lEC 200 (1966) METHODS OF MEASUREMENT FOR LOUDSPEAKERS.

This Recommendation applies only to a single direct-radiator electrodynamic

loudspeaker of the moving-coil type. If the terminals representing the moving

coil are available, it is recommended that they be used, as this gives

information about the unit in its most basic form. However, where other

elements such as a transformer or a special network form part of the unit, or are prescribed in the manufacturer's specification to be used with the unit, it

may be so tested provided that this is clearly stated when presenting the

results. Provision is made for different acoustic loads by prescribing three

types of mounting.

The object of this Recommendation is to specify, on the simplest possible

basis, practical and uniform methods of measuring certain characteristics of

loudspeakers, so that discussions between suppliers, users and testing

authorities may be based on clearly expressed and reproducible results. The

interpretation of the results and an assessment of actual performance are matters of the individual users' experience. This is because uniformity of

measuring conditions demands a radical simplification of the acoustical

environment, which is an important factor for determining loudspeaker

performance; moreover, it should be remembered that the ultimate appeal is to human judgment. For these reasons, the objective measurements recommended need

to be supplemented by subjective listening tests under the appropriate

conditions if a final assessment is to be roade.

23.1.12 lEC 225 (1966) OCTAVE, HALF-OCTAVE AND THIRD-OCTAVE BAND FILTERS INTENDED FOR

THE ANALYSIS OF SOUNDS AND VIBRATIONS.

This Recommendation applies to band filters commonly known as octave,

half-octave and third-octave band filters of the passive or active type, the

latter including amplifier elements, e.g., tubes, valves and/or transistors.

It specifies the most important characteristics of these filters together

with the corresponding tolerances.

The object of the Recommendation is to specify the characteristics of

band-pass filters to be used in sound and vibration analysis for which octave

and third-octave band-pass filters are preferred.

(Note: Also see ANSI SI. 11-1966 (R1971).)

23.1.13 lEC 303 (1970) lEC PROVISIONAL REFERENCE COUPLER FOR THE CALIBRATION OF

EARPHONES USED IN AUDIOMETRY.

This report describes an interim reference coupler for loading an earphone

with a specified acoustic impedance, when calibrating audiometers, in the

frequency range of 125 to 8000 Hz. One configuration of this coupler is identical

with the National Bureau of Standards 9-A coupler.

The sound pressure developed by an earphone is not, in general, the same in

the coupler as in a person's ear. However, the lEC recommends its use as a

34
simple and ready means for the exchange of specifications on audiometers and for

the calibration of earphones used in audiometry.

23.1.14 lEC 318 (1970) AN lEC ARTIFICIAL EAR, OF THE WIDE BAND TYPE, FOR THE CALIBRATION

OF EARPHONES USED IN AUDIOMETRY.

This Recommendation relates to the specification of an artificial ear which

covers the frequency band 20 to 10000 Hz and is intended for calibrating

supra-aural earphones applied to the ear without acoustical leakage. This

device is not intended for the calibration of circumaural earphones.

/

The audiometric artificial ear is a device to permit calibration of

earphones used in audiometry and comprises a microphone to measure the sound

pressure and an acoustical network so constructed that the acoustical

characteristics of the whole approximate to the acoustical characteristics of

the mean external human ear.

23.1.15 lEC 327 (1971) PRECISION METHOD FOR THE PRESSURE CALIBRATION OF ONE-INCH

STANDARD CONDENSER MICROPHONES BY THE RECIPROCITY TECHNIQUE.

This Recommendation describes the calibration of one-inch condenser

microphones used as laboratory standards. It is restricted to reciprocity

pressure calibration by the coupler method.

(Note: Also see ANSI SI. 10-1966 (R1971).)

23.1.16 lEC 402 (1972) SIMPLIFIED METHODS FOR PRESSURE CALIBRATION OF ONE-INCH CONDENSER

MICROPHONES BY THE RECIPROCITY TECHNIQUE.

This Recommendation describes a simplified technique for calibration of

condenser microphone cartridges, commonly known as one-inch microphones, based

upon reciprocity pressure calibration by the coupler method. The object of this

Recommendation is to specify a method of absolute pressure calibration of

one-inch condenser microphones used in laboratories for conventional measuring

purposes, without requiring the highest obtainable accuracy. The frequency

range of the calibration is restricted to 50 Hz-10 kHz.

The calibration method described is based on the reciprocity technique

using air in a closed cavity as the coupling medium between the microphones.

The calibration procedure is simplified — at the expense of the total accuracy

of the calibration — in order that the calibration can be carried out without

using the most advanced instrumentation and techniques. The error introduced by

using this simplified method is estimated to be less than 0.3 dB.

Procedures giving a higher accuracy of calibration are described in lEC

Publication 327: Precision Method for Pressure Calibration of One-inch Standard

Condenser Microphones by the Reciprocity Technique.

23.1.17 lEC 486 (1974) PRECISION METHOD FOR FREE-FIELD CALIBRATION OF ONE-INCH STANDARD

CONDENSER MICROPHONES BY THE RECIPROCITY TECHNIQUE.

This lEC Recommendation describes a method for the free-field reciprocity

calibration of one-inch condenser microphone capsules used as laboratory

standards

The object of this recommendation is to specify methods of measuring

certain characteristics of standard condenser microphones with high accuracy, so that discussions between testing authorities may be based on clearly expressed

and reproducible results. Although the free-field calibration of condenser

microphones is a problem of a general nature, this recommendation (as regards

specific figures, measures and numbers) is restricted to microphones commonly

known as one-inch condenser microphones, having a nominal outer diameter of

0.936 in = 23.77 mm.

35
23.2. Draft Proposals for New Standards r.ffcjir

23.2.1 DEFINITION OF DYNAMIC RANGES AT THE INPUT OF DIGITAL SIGNAL PROCESSING EQUIPMENT

FOR ACOUSTICAL MEASUREMENTS.

23.2.2 ELECTRO-ACOUSTICAL PERFORMANCE REQUIREMENTS FOR AIRCRAFT NOISE CERTIFICATION

MEASUREMENTS.

23.2.3 AUDIOMETERS.

23.2.4 FREQUENCY WEIGHTING FOR THE MEASUREMENT OF AIRCRAFT NOISE (D-WEIGHTING)

23.2.5 SUPPLEMENT TO lEC 118: RECOMMENDED METHODS FOR MEASUREMENT OF

ELECTRO-ACOUSTICAL CHARACTERISTICS OF HEARING AIDS WITH AUTOMATIC GAIN CONTROL

(AGC) CIRCUITS.

23.2.6 CONSOLIDATION AND REVISION OF lEC 123 AND lEC 179 SOUND LEVEL METERS.

36
24 . International Organization for Standardization (ISO)

Purchase standards from:

American National Standards Institute

1430 Broadway

New York, NY 10018

24.1. Summary of Standards

24.1.1 ISO R31 PART VII-1965 QUANTITIES AND UNITS OF ACOUSTICS.

This ISO Recommendation is part of a more comprehensive publication dealing

with quantities and units in various fields of science and technology. It consists of a table listing the various quantities and units of acoustics, and the

respective symbols. Preference is given to the International System of Units.

24.1.2 ISO R131-1959 EXPRESSION OF THE PHYSICAL AND SUBJECTIVE MAGNITUDES OF SOUND OR

NOISE.

This ISO Recommendation states that the physical magnitude of sound or noise

be expressed by a statement of sound pressure, power or Intensity level, and the

subjective magnitude as a loudness level in phons or loudness in sones. It also

states the Interrelationship between phons and sones.

24.1.3 ISO R140-1960 FIELD AND LABORATORY MEASUREMENTS OF AIRBORNE AND IMPACT SOUND

TRANSMISSION.

This ISO Recommendation defines methods for measuring the airborne sound

insulation of walls and floors, and impact sound on floors, both in the field and

in the laboratory.

The way in which the airborne and impact sound fields are generated, the

frequency range of measurement and the characteristics of the necessary filters

are described. Definitions are also given of the quantity measured in each case, and of the method of normalizing the results to make them comparable.

24.1.4 ISO R226-1961 NORMAL EQUAL-LOUDNESS CONTOURS FOR PURE TONES AND NORMAL THRESHOLD

OF HEARING UNDER FREE FIELD LISTENING CONDITIONS.

This ISO Recommendation specifies, for the frequency range 20 to 15000 Hz:

(a) The standard relations existing between sound pressure level and frequency for

pure tones of equal loudness presented frontally to a listener in a free field.

(b) Values for the standard threshold of hearing for pure tones presented

frontally in a free field.

24.1.5 ISO 266-1975 ACOUSTICS - PREFERRED FREQUENCIES FOR ACOUSTICAL MEASUREMENTS (Agrees

with ANSI SI. 6-1967 (R1971).)

This ISO Standard deals with the frequencies used for acoustical

measurements. The variety of frequencies being used for acoustical measurement

make comparison of results inconvenient. Some of the difficulties arise from the use of frequencies spaced at different intervals or of series starting from

different reference frequencies. The purpose therefore, of this ISO

Recommendation is to refer all frequency-series to a single reference frequency,

and to select other frequencies in such a way as to afford a maximum number of common frequencies in the various series.

For certain acoustical measurements, a constant frequency increment is a suitable spacing. More commonly, however, a constant percentage increment is

adopted and the test frequencies then form a geometric series. The present ISO

Recommendation deals with the geometric series and is not Intended to apply to cases where a constant frequency Increment, or other particular spacing would be

37
more suitable, or where there may be good reasons for the adoption or retention

of other frequencies.

. iO .

^ 24.1.6 ISO R354-1963 MEASUREMENT OF ABSORPTION COEFFICIENTS IN A REVERBERATION ROOM.

This ISO Recommendation describes how a reverberation room should be used to measure, under specified conditions, the sound absorption coefficients of

acoustical materials used as wall or ceiling treatments, or the sound absorption

of separate objects, such as furniture, persons or space absorbers. The general

principle is that the specimen is introduced into the room and the absorption

added is computed from measurements of the reverberation time of the room (or the

decay rate of the reverberant sound) before and after the introduction of the

specimen.

It specifies certain features of the size and shape of the room, the size and

disposition of the test specimen, the methods of measuring the reverberation time

(or the decay rate of the reverberant sound) and of computing the results, the

frequencies to be used and the manner in which the results should be stated.

24.1.7 ISO R357-1963 SUPPLEMENTARY TO R131) . EXPRESSION OF THE POWER AND INTENSITY

LEVELS OF SOUND OR NOISE.

This ISO Recommendation defines the reference sound power and sound intensity

and recommends one picowatt as the reference sound power and one picowatt per

square meter as the reference intensity.

24.1.8 ISO R362-1964 MEASUREMENT OF NOISE EMITTED BY VEHICLES.

This ISO Recommendation describes methods of determining the noise emitted by

motor vehicles, these being intended to meet the requirements of simplicity as far

as is consistent with reproducibility of results and realism in the operating

conditions of the vehicle.

It is based primarily .on a test with vehicles in motion, the ISO reference

test. It is generally recognized to be of primary importance that the

measurements should relate to normal town driving conditions, thus including

transmission noise, etc. Measurements should also relate to vehicle conditions

which give the highest noise level consistent with normal driving and which lead

to reproducible noise emission. Therefore, an acceleration test at full throttle

from a stated running condition is specified.

Recognizing, however, that different practices were in existence before this

Recommendation, specifications of two other methods used are also given in the

Appendix. These relate to (a) a test with stationary vehicles, and (b) a test with vehicles in motion, under vehicle conditions which (in the case of certain

vehicles) are different from those in the ISO reference test. When either of

these tests is used, the relation between the results and those obtained by the

ISO reference test should be established for typical examples of the model

concerned

.

24.1.9 ISO 389-1975 ACOUSTICS STANDARD REFERENCE ZERO FOR THE CALIBRATION OF PURE-TONE

AUDIOMETERS

.

This ISO standard specifies a standard reference zero for the scale of

hearing threshold level applicable to pure-tone audiometers. It states the

information in terms of the sound pressure level output of an earphone or an artificial ear or coupler for five different National Standard earphone-coupler

combinations. The five sets of reference equivalent threshold sound pressure

levels (RETSPL) all refer to the same auditory threshold levels. That is when an earphone, actuated by a voltage that sets up the proper RETSPL in the coupler, is

placed on the ear, the applied voltage corresponds to the threshold of hearing.

In addition it gives the corresponding reference equivalent threshold sound

pressure levels for eleven audiometric earphones referred to a single type of

38
coupler, namely, the National Bureau of Standards, Washington, D. C, USA, Type

9-A Coupler. Of these eleven earphones, five are those currently used as reference standards in a number of standardizing laboratories, and the remaining

six are other types which have been used on commercial equipment and in

audiometric laboratories.

24.1.10 ISO R4 54-1965 RELATION BETWEEN SOUND PRESSURE LEVELS OR NARROW BANDS OF NOISE IN A

DIFFUSE FIELD AND IN A FRONTALLY- INCIDENT FREE FIELD FOR EQUAL LOUDNESS.

This ISO Recommendation specifies, for the frequency range 50 to 10,000 Hz,

the difference (in decibels) between sound pressure levels for equal loudness of narrow bands of noise in diffuse and f rontally-incident- free sound fields,

respectively, under the following conditions:

a) The sound pressure level is measured in the absence of the listener.

b) The listening is binaural. '

,:

c) The listeners are otologically normal persons in the age group from 18 to 25 years.

Note: An "otologically normal subject" is understood to be a person in

a normal state of health who is free from all signs or symptoms of ear disease and from wax in the ear canal.

d) The sound is a narrow band of noise of less than critical bandwidth.

24.1.11 ISO R495-1966 GENERAL REQUIREMENTS FOR THE PREPARATION OF TEST CODES FOR MEASURING

THE NOISE EMITTED BY MACHINES.

This ISO Recommendation is concerned with the procedures to be followed in

the objective measurement of the noise emitted by machines. These procedures are

not necessarily applicable to noise of an impulsive character. The aim is to indicate the general principles by which specific test codes for noise

measurements may be formulated. These general rules give different methods for

measuring noise. The specific codes for the various types of machines will have

to select the most suitable method having regard to the size of the machine and

its application. The codes themselves should contain all the necessary

particulars to enable a result to be obtained with the required accuracy. .

-.

24.1.12 ISO R507-1970 PROCEDURE FOR DESCRIBING AIRCRAFT NOISE AROUND AN AIRPORT,

This ISO Recommendation provides a means for describing the noise on the

ground around an airport produced by one or a number of aircraft, of the same type

of different types, operating under any known set of conditions. It specifies the

five steps to be followed for this purpose:

a) A method of measurement of the noise.

b) A method of calculating from these data tone-corrected perceived noise

levels, taking into account pronounced irregularities in the spectrum

such as when pure tones are present.

c) A method of integrating the tone-corrected perceived noise level, thus

taking duration into account, to arrive at an effective perceived noise

level

d) A method for mapping noise contours around an airport.

e) Methods of integrating the perceived noise levels due to a number of

takeoff and landing operations in a specified period of time to obtain

the total aircraft (perceived) noise exposure level, and to obtain the

equivalent continuous perceived noise level for that same period.

39
It is outside the scope (1) to apply this ISO Recoiranendation directly to helicopters or vertical take-off flight vehicles; or (2) to describe a method for

computing from engine data the noise field produced on the ground by a future

aircraft

.

24.1.13 ISO 512-1974 ROAD VEHICLES - SOUND SIGNALLING DEVICES ON MOTOR VEHICLES, ACOUSTIC

STANDARDS AND TECHNICAL SPECIFICATIONS.

This ISO Recommendation deals with sound signalling devices (a) mounted on motor vehicles, (b) functioning with an electrical current, and (c) designed for use outside built-up areas. The aim of this ISO Recommendation is to specify

their acoustic properties, such as spectral distribution of acoustic power and

sound pressure level, and also their test conditions.

24.1.14 ISO 532-1975 ACOUSTICS - METHOD FOR CALCULATING LOUDNESS LEVEL

This ISO Standard specifies two methods for calculating the loudness or loudness level of a complex sound, which differ not only in the method of analysis

of the sound, but also in the principles of computation. The first. Method A,

utilizes physical measurements obtained from spectrum analysis in terms of octave

bands. The second. Method B, utilizes spectrum analysis in terms of one-third

•-

. octave bands

.

24.1.15 ISO R717-1968 RATING OF SOUND INSULATION FOR DWELLINGS.

This ISO Recommendation describes a method of evaluating the airborne sound

insulation and impact sound level in dwellings when the results of measurements

made by the method described in ISO Recommendation R140 are available. Reference

values at different frequencies are given against which measured values can be

compared to arrive at a single airborne sound insulation index and impact-sound

index respectively.

24.1.16 ISO R1680-1970 TEST CODE FOR THE MEASUREMENT OF THE AIRBORNE NOISE EMITTED BY ROTATING ELECTRICAL MACHINERY.

This ISO Recommendation has been drafted in accordance with ISO

Recommendation R495, and gives the detailed instructions for conducting and

reporting tests on rotating electrical machines, to determine the airborne noise

characteristics under steady-state conditions.

The test code is divided into two parts — Part I: Methods for usual tests based on A-weighted sound level measurements, and Part II: Methods for special

tests based on frequency band analysis measurements. . -

:i This test code for the measurement of noise applies to rotating electrical

• machines such as motors and generators of all sizes without limitation of output

or voltage, when fitted with their normal auxiliaries.

24.1.17 ISO R1761-1970 MONITORING AIRCRAFT NOISE AROUND AN AIRPORT.

This ISO Recommendation describes methods for monitoring, on the ground, the

noise produced by aircraft around an airport, and equipment to be used. .

Monitoring is understood to be routine measurement of noise created by

aircraft in the operation of an airport. Monitoring usually involves a large

number of measurements per day, from each of which an immediate indication of the

noise may be required.

Monitoring aircraft noise can be carried out either with mobile equipment,

often with only a sound level meter, or with permanently installed equipment

incorporating one or more microphones with amplifiers located at different

positions in the field with a data transmission system linking the microphones to

40
a central recording installation. This ISO Reccmni.endation describes primarily the

latter method, but specifications given in this ISO Recommendation should also be

followed when using mobile equipment to the extent to which the specifications are

relevant.

The noise levels to be reported according to this Recommendation are . '.. approximations to perceived noise level (PNL)

24.1.18 ISO R199 6-1971 ACOUSTICS - ASSESSMENT OF NOISE WITH RESPECT TO COMMUNITY RESPONSE.

The reduction, or lim.itation, of noise which causes annoyance is of

increasing general importance. This ISO Recommendation suggests methods for

measuring and rating noises in residential, industrial and traffic areas with

respect to their interference with rest, working efficiency, social activities and

tranquility.

The Recommendation calls for measurement of A-weighted sound level in

decibels. The equivalent steady sound level is obtained by appropriate

measurement of the fluctuating noise in a community, or by duration corrections

added to measured maximum sound levels. Further corrections are added to the

equivalent steady sound level for impulsive or tonal character, to determine the

rating sound level. A criterion noise level is described that is further adjusted

for time of day and type of district; in special cases the prevailing ambient

noise in the community, in the absence of allegedly offending noise, may be used

as the adjusted criterion noise level. The actual assessment of noise with

respect to community response is obtained from the amount in decibels by which the

rating sound level exceeds the adjusted criterion noise level.

When corrective measures are required, a frequency analysis of the offending

noise may be necessary. The resulting noise spectrum may be compared with

noise-rating (NR) curves given in the Appendix, in order to identify the frequency

bands in which the offending noise is predominant.

" - i

. ^ -, 24.1.19 ISO R1999-1975 ACOUSTICS - ASSESSMENT OF OCCUPATIONAL NOISE EXPOSURE FOR HEARING

CONSERVATION PURPOSES.

This ISO Recommendation provides a method for estimating risks of hearing

impairment due to exposure to noise. It is intended to facilitate the setting of

limits for tolerable exposure to noise during work, and the institution of

programs for conservation of hearing.

The equivalent continuous noise level to which a person is exposed during a 40-hour work week is to be calculated from the A-weighted sound level and duration

of each noise. From a table in the Recommendation, a partial noise exposure index

can be assigned to each noise. The sum of these indices is the composite noise

exposure index. Corresponding to this composite noise exposure index, in a second

table, the equivalent continuous sound level and the risk of impairment of hearing

(for conversational speech) that will occur solely as a result of exposure to the

noise during normal working periods up to 45 years. This is risk in addition to that of normal aging.

When noise control means are adopted to reduce the noise to which a person is

exposed, it may be necessary to analyze the noise in octave or 1/3 octave bands.

An example is given in the Appendix for calculating from an octave band spectrum

the A-weighted sound level to which a person wearing ear protectors is exposed.

The Recommendation does not apply to impulsive noises consisting of noises of

a duration each less than one second, or single, short, high-level transients such

as from gunfire.

41
24.1.20 ISO R2151-1972 MEASUREMENT OF AIRBORNE NOISE EMITTED BY COMPRESSOR/ PRIMEMOVER

UNITS INTENDED FOR OUTDOOR USE.

This ISO Recommendation is designed to assist in the measurement of airborne

noise emitted by outdoor compressors. The information is then used to (a) predict

the disturbance in the neighborhood of a particular machine, (b) assess the risk

of hearing damage for people working in the immediate vicinity of the machine, or

(c) compare the acoustic properties of different makes of machines.

This Recommendation specifies a method of determining, for the above listed

purposes, the air-borne sound emitted by compressor/primemover units intended for

outdoor use and gives instructions for conducting the tests and reporting the

results

.

24.1.21 ISO R2204-1973 GUIDE TO THE MEASUREMENT OF ACOUSTICAL NOISE AND EVALUATION OF ITS

EFFECT ON MAN.

This ISO Recommendation is a guide to the general procedures for the

measurement of noise and evaluation of its effects on man. It is intended as an introduction to the more specialized instructions contained in acoustical test codes and interpretation procedures published by national and international

standardizing bodies.

24.1.22 ISO 2249-1973 ACOUSTICS - DESCRIPTION AND MEASUREMENT OF PHYSICAL PROPERTIES OF

SONIC BOOMS.

The ISO Standard establishes the terminology for describing the physical

properties of sonic booms caused by overflight of supersonic aircraft, and

specifies the minimum performance requirements of equipment and the method to be

used for their measurement. The conditions of measurement envisaged include those

in which the direction and time of arrival of the pressure disturbance and even

its approximate intensity are not necessarily known in advance. The standard

provides the basis for the measurement and description of sonic boom pressure signatures suitable for evaluating their effects on people, structures, animals and

unstable terrain features.

24.1.23 ISO 2922-1975 ACOUSTICS - MEASUREMENTS OF NOISE EMITTED BY VESSELS ON INLAND

WATER-WAYS AND HARBOURS.

This ISO Standard specifies the conditions for obtaining reproducible and

comparable measurements of the noise level and the noise spectrum emitted by

vessels of all kinds on inland water-ways and harbours. This International

Standard can also be applied to small sea-going vessels, harbour vessels and

dredgers. Specifications for intake or exhaust noise measurement and measurements

with stationary vessels are also given.

24.1.24 ISO 2923-1975 ACOUSTICS - MEASUREMENT OF NOISE ON BOARD VESSELS.

This ISO Standard specifies the conditions for obtaining reproducible and

comparable measurements of the noise level and the noise spectrum on board

vessels. The results may be used, for example, to compare various vessels; to characterize the acoustic comfort on board these vessels; and to orient a program

of more elaborate measurements for the purposes of studying noise reduction

procedures.

24.1.25 ISO 3095-1975 ACOUSTICS - MEASUREMENT OF NOISE EMITTED BY RAILBOUND VEHICLES.

This ISO Standard specifies the conditions for obtaining reproducible and

comparable measurements of the noise level and the noise spectrum emitted by all

kinds of vehicles operating on rails or other types of fixed track.

Specifications for exhaust or air-intake noise measurement and measurements with

stationary and accelerating vehicles and for me^^surements at stations, on bridges

or viaducts and in tunnels are also given.

42
24.1.26 ISO/TR 3352-1974 ACOUSTICS - ASSESSMENT OF NOISE WITH RESPECT TO ITS EFFECT ON THE

INTELLIGIBILITY OF SPEECH.

This ISO Technical Report describes a practical survey method for assessment

of the influence of noise on sentence intelligibility in direct communication. A

simplified method is described for the estimation of the maximum distance between

speaker and listener as a function of the characteristics of the noise. .

24.1.27 ISO 3741-1975 ACOUSTICS - DETERMINATION OF SOUND POWER LEVEL OF NOISE SOURCES - PRECISION METHODS FOR BROAD-BAND SOURCES IN REVERBERATION ROOMS.

This ISO Standard specifies a direct method and a comparison method for

determining the sound power level produced by a source. It specifies test room

requirements, source location and operating conditions, instrumentation and

techniques for obtaining an estimate of mean-square sound pressure from which the

sound power level of the source in octave or one-third octave bands is calculated.

24.1.28 ISO 3742-1975 ACOUSTICS - DETERMINATION OF SOUND POWER LEVEL OF NOISE SOURCES - PRECISION METHODS FOR DISCRETE-FREQUENCY AND NARROW-BAND SOURCES IN REVERBERATION

ROOMS

This ISO Standard specifies the special requirements that are necessary for

accurate determinations of the sound power when discrete frequencies or narrow

bands of noise are radiated by a source.

24.2. Draft Proposals for New Standards

24.2.1 ISO/DIS 3381 ACOUSTICS - MEASUREMENT OF NOISE INSIDE RAILBOUND VEHICLES.

24.2.2 ISO/DIS 3382 ACOUSTICS - MEASUREMENT OF REVERBERATION TIME IN AUDITORIES.

24.2.3 ISO/DIS 3481 ACOUSTICS - MEASUREMENT OF AIRBORNE NOISE EMITTED BY PNEUMATIC TOOLS

AND MACHINES - ENGINEERING METHOD FOR DETERMINATION OF SOUND POWER LEVELS.

24.2.4 ISO/DIS 3740 ACOUSTICS - DETERMINATION OF SOUND POWER LEVEL OF NOISE SOURCES - ENGINEERING METHODS FOR SPECIAL REVERBERATION TEST ROOMS. Part 0: GUIDELINES FOR

THE USE OF BASIC STANDARDS AND FOR THE PREPARATION OF NOISE TEST CODES.

24.2.5 ISO/DIS 3743 ACOUSTICS - DETERMINATION OF SOUND POWER LEVEL OF NOISE SOURCES - ENGINEERING METHODS FOR SPECIAL REVERBERATION TEST ROOMS.

24.2.6 ISO/DIS 3744 ACOUSTICS - DETERMINATION OF SOUND POWER LEVELS OF NOISE SOURCES - ENGINEERING METHODS FOR FREE FIELD CONDITIONS OVER A REFLECTING PLANE.

24.2.7 ISO/DIS 374 5 ACOUSTICS - DETERMINATION OF SOUND POWER LEVELS OF NOISE SOURCES - PRECISION METHODS FOR ANECHOIC AND SEMI-ANECHOIC ROOMS.

24.2.8 ISO/DIS 374 6 ACOUSTICS - DETERMINATION OF SOUND POWER LEVELS OF NOISE SOURCES.

SURVEY METHODS.

24.2.9 ISO/DIS 3891 ACOUSTICS - PROCEDURE FOR DESCRIBING AIRCRAFT NOISE HEARD ON THE

GROUND ( REVISION OF ISO R/507-1966 AND ISO R/1761-1970)

24.2.10 LABORATORY TESTS ON NOISE EMISSIONS BY APPLIANCES AND EQUIPMENT IN WATER SUPPLY

INSTALLATIONS

24.2.11 SOUND MEASUREMENT PROCEDURES FOR AIR MOVING DEVICES CONNECTED TO EITHER A

DISCHARGE DUCT OR AN INLET DUCT.

24.2.12 A GUIDE TO THE EVALUATION OR ASSESSMENT OF NOISE.

24.2.13 REVERBERATION ROOM MEASUREMENT OF SOUND FROM HEATING, VENTILATING AND AIR

CONDITIONING EQUIPMENT.

24.2.14 METHODS OF MEASUREMENT OF NOISE INSIDE MOTOR VEHICLES.

43
24.2.15 MEASUREMENT OF NOISE INSIDE AIRCRAFT.

24.2.16 DIGITAL PROCESSING OF ACOUSTICAL SIGNALS.

24.2.17 CODE OF NOISE CLASSIFICATION OF PNEUMATIC EQUIPMENT FOR CONSTRUCTION SITES.

24.2.18 NOISE LEVEL MEASUREMENT AT THE OPERATOR'S WORKPLACE ON AGRICULTURAL TRACTORS AND

FIELD MACHINERY.

24.2.19 ACOUSTICS - NOISE FROM EARTH MOVING MACHINERY - DETERMINATION OF SOUND POWER

LEVEL

.

24.2.20 METHOD OF CONTROL OF NOISE EMITTED BY STATIONARY MOTOR VEHICLES.

24.2.21 THE MF.ASUREMENT OF AIRBORNE NOISE EMITTED BY COMPRESSOR UNITS INCLUDING

PRIMEMOVERS - ENGINEERING METHOD FOR DETERMINATION OF SOUND POWER LEVEL.

'

24.2.22 ACOUSTICS - NOISE FROM EARTH MOVING MACHINERY - MEASUREMENT AT OPERATOR'S

WORKPLACE.

24.2.23 ACOUSTICS - DETERMINATION OF AIRBORNE NOISE EMITTED BY EARTH MOVING MACHINERY TO THE SURROUNDINGS - SURVEY METHOD.

24.2.24 ACOUSTICS - DETERMINATION OF AIRBORNE NOISE EMITTED BY CIVIL ENGINEERING EQUIPMENT

FOR OUTDOOR USE.

24.2.25 ACOUSTICS - SURVEY METHOD FOR THE MEASUREMENT OF NOISE EMITTED BY STATIONARY

VEHICLES

.

24.2.26 ACOUSTICS - MEASUREMENT OF NOISE EMITTED BY ROAD VEHICLES.

24.2.27 ACOUSTICS - DESIGNATION OF NOISE EMITTED BY MACHINERY AND EQUIPMENT.

24.2.28 ACOUSTICS - RECOMMENDED METHODS FOR MEASURING THE INTELLIGIBILITY OF SPEECH.

24.2.29 ACOUSTICS - MEASUREMENT OF SOUND ATTENUATION OF HEARING PROTECTORS.

24.2.30 ACOUSTICS - NOISE CLASSIFICATION OF EQUIPMENT AND MACHINERY.

24.2.31 REFERENCE ACOUSTICAL QUANTITIES. '

'"

44
25 . Military Specifications

Purchase standards from:

Commanding Officer

Naval Publications and Forms Center . . .1 , . 5801 Tabor Avenue ' "

, •

' Philadelphia, PA 19120 ,

, . . . , , -....^ .

25.1. Summary of Standards ' ,'

25.1.1 MIL-S-503A (1971) SIRENS, ELECTRIC, 2 and 5 HORSEPOWER. ' '

'

This specification covers nondirectional electric-motor-driven sirens rated

at 600 volts or less, complete with all controls and auxiliary equipment and

suitable for mounting in the open on roofs or other supporting structures without

additional protection from the weather.

25.1.2 MIL-STD-740B (SHIPS) (1965) AIRBORNE AND STRUCTUREBORNE NOISE MEASUREMENTS AND '•, ACCEPTANCE CRITERIA OF SHIPBOARD EQUIPMENT. ... .

,

'

This standard covers acceptable instrumentation and procedures for the

measurement of and acceptance criteria for, airborne and structureborne noise of

Naval shipboard equipment. This Standard is intended to supplement equipment,

shipbuilding and purchase specifications, and similar documents, applicable to all

Naval shipboard equipment required to be quieter than equipment produced by normal

production practices, except that structureborne noise requirements for main propulsion turbines, main reduction gears, and ship service turbine generator sets are not covered by this standard and will be found in the applicable equipment

document

25.1.3 MIL-STD-1474A (MI) (1975) NOISE LIMITS FOR ARMY MATERIEL. ' '

'

This standard establishes acoustical noise limits for Army materiel and

prescribes the testing requirements and measurement techniques for determining

conformance to the noise limits herein. Adherence to the provisions of this

standard is intended to; (a) reduce hearing loss among personnel exposed to noise

caused by Army materiel; (b) improve speech communications in the noise

environment of Army materiel; (c) when appropriate, decrease possibility of aural

detection of Army materiel by an enemy; (d) assure that Army materiel meets

applicable state and federal noise limits as well as the provisions of TB MED 251.

This standard is neither a hearing damage-risk criterion nor a hearing

conservation criterion. It is a design standard, evolved from consideration of

hearing damage-risk, speech intelligibility, aural detection, state-of-the-art of

noise reduction and federal and state legislation, and is intended to cover typical operational conditions. This standard is applicable to design of all new

systems, subsystems, equipment and facilities which emit acoustic noise to personnel areas.

25.1.4 MIL-STD-1621A (NAVY) (1973) ACOUSTICAL AND VIBRATIONAL STANDARD REFERENCE

QUANTITIES.

This standard covers reference quantities to be used in reporting of all

acoustical and vibrational quantities expressed in terms of levels. It also

defines acoustical terms and prescribes the plotting format for acoustical

measurements. This standard applies to new construction and to procurement

contracts for installed systems and equipment. It also applies to the reporting

of acoustical data generally, except where old construction and procurement

contracts for Installed systems require otherwise. It does not apply to acoustical ranging to determing vulnerability to acoustical mines.

45
25.1.5 MIL-S-3485B (1966) SIRENS, ELECTRIC-MOTOR-OPERATED, VEHICULAR.

This specification covers weatherproof electric-motor-driven sirens with and

without a flasher light for vehicles.

25.1.6 MIL-S-6144A (1963) SOUND AND THERMAL INSULATION FOR AIRCRAFT, GENERAL

SPECIFICATION FOR THE INSTALLATION OF.

This specification covers general requirements for the installation of sound

and thermal insulation in aircraft.

25.1.7 MIL-A-8806A (1) (1961) ACOUSTICAL NOISE LEVEL IN AIRCRAFT, GENERAL SPECIFICATION

FOR.

This Specification covers the general requirements for the control of

acoustical noise in occupied spaces of aircraft, including the acceptable noise

levels and the testing requirements for determining conformance to these levels.

25.1.8 MIL-S-008806B (1970) SOUND PRESSURE LEVELS IN AIRCRAFT, GENERAL SPECIFICATION FOR.

This limited coordination military specification has been prepared by the Air

Force based upon currently available technical information, but is has not been

approved for promulgation as a revision of Military Specification MIL-A-8806. It is subject to modification. However, pending its promulgation as a coordinated

military specification, it may be used in procurement.

This Specification covers the general requirements for maximum allowable

sound pressure levels in aircraft crew and passenger compartments and the testing

requirements for determining conformance to these levels.

25.1.9 MIL-A-15303M (SHIPS) (1969) AUDIBLE SIGNALS: ALARMS, BELLS, BUZZERS, HORNS AND

SIRENS - SHIPBOARD.

This specification covers various types of audible signals for alarm and

signaling purposes on Navy ships.

25.1.10 MIL-A-23054 (SHIPS) (1961) ACOUSTICAL ABSORPTIVE BOARD, FIBROUS GLASS, PERFORATED

FIBROUS GLASS CLOTH FACED. ,

This specification covers fibrous glass acoustical absorptive board with a perforated fibrous glass cloth facing.

25.1.11 MIL-S-527 39 (ME) (1973) SIRENS: ELECTRIC-MOTOR, FLUID AND INTERNAL COMBUSTION

ENGINE OPERATED.

This specification covers electric-motor-driven, air and steam, and internal

combustion engine operated sirens.

46
26 . National Electrical Manufacturers Association (NEMA)

Purchase standards from:

National Electrical Manufacturers Association

815 15th Street, Ste. 438

Washington, D.C. 20005

26.1. Summary of Standards

26.1.1 NEMA LE2-1974 H-I-D LIGHTING SYSTEM NOISE CRITERION (LS-NC) RATINGS.

This Standards Publication includes definitions and a description of the

testing facilities and equipment, testing procedures and calculation procedures to determine a rating, consisting of a single number, which will describe the

background noise level of an enclosed space that will mask the hum produced by

H-I-D lighting systems. The rating In accordance with this publication is known

as the "Lighting System Noise Criterion (LS-NC) Rating".

26.1.2 NEMA MGl-12.49 (1972) MOTORS AND GENERATORS METHODS OF MEASURING MACHINE NOISE.

This Standard describes test methods for measuring the noise levels

associated with unloaded motors and generators. The methods are those of the IEEE

Publication Number 85.

26.1.3 NEMA MG3-1974 SOUND LEVEL PREDICTION FOR INSTALLED ROTATING ELECTRICAL MACHINES.

Due to the recent emphasis on health and safety considerations, a large

number of people with no special training in sound have had noise control problems

thrust upon them. This booklet provides a method of predicting approximate sound

pressure levels in industrial and commercial areas. The method is intended for

estimating sound pressure levels and should not be construed as a guarantee of

results. It requires a knowledge of the sound levels, location of all sound

sources, and room characteristics. For simplicity, emphasis is placed on the use

of overall A-welghted sound levels.

26.1.4 NEMA TRl-1974 TRANSFORMERS, REGULATORS AND REACTORS (SECTION 9-04 AUDIBLE SOUND

LEVEL TESTS)

This Standard lists test conditions and measurement procedures for

determining the audible sound level associated with transformers under field

conditions

26.1.5 NEMA SM33-1964 GAS TURBINE SOUND AND ITS REDUCTION. (Discontinued, See Scope.)

This Standards Publication contains Information relative to gas turbine inlet

and exhaust Sound Pressure Levels and sound reduction to satisfy surrounding

neighborhood requirements external to the turbine room in the far field (airborne

sound). (Other sources of sound, such as fans for oil coolers, acoustic leakage

through buildings housing the equipment, etc., are not covered in this

publication .

)

(This standard has been discontinued by NEMA due to their departure from the gas

turbine field. It is Included since it is still being used by individuals active

in the gas turbine field.)

47
27 . National Fluid Power Association (NFPA)

Purchase standards from:

National Fluid Power Association

3333 N. Mayfalr Road

Milwaukee, WI 53222 - - "

27.1. Summary of Standards

27.1.1 NFPA T39. 12-1970 (R1975) METHOD OF MEASURING SOUND GENERATED BY HYDRAULIC FLUID

POWER PUMPS.

This Standard considers only sound directly radiated from hydraulic fluid

power pumps in terms of loudness, disregarding Installation effects. Its purpose

is to establish a uniform basis for measuring, reporting, and accurately comparing

the sound levels of such pumps.

27.1.2 NFPA T3.9.14 (1971) METHOD OF MEASURING SOUND GENERATED BY HYDR.\ULIC FLUID POWER

MOTORS.

This Standard considers only sound directly radiated from hydraulic fluid

power rotary motors in terms of loudness, disregarding installation effects. Its purpose is to establish a uniform basis for measuring, reporting, and accurately

comparing the sound levels of such motors.

2 7.2. Draft Proposals for New Standards

27.2.1 NFPA T39.24-19XX DETERMINATION OF FLUID BORNE NOISE LEVEL OF HYDRAULIC FLUID POWER

PUMPS.

48
28 . National Machine Tool Builders Association CNMTBA)

Purchase standards from:

National Machine Tool Builders Association '

• 7901 West Park Drive

McLean, VA 22101

28.1. Summary of Standards

28.1.1 NMBTA TECHNIQUE (1970) NOISE MEASUREMENT TECHNIQUES .

• ' '' '

'

The purpose of this document is to delineate suggested measuring techniques

and procedures for the determination of noise emanating from machine tools. These

procedures apply to measurements made in facilities under the control of the

machine tool builder. As such it is assumed that the builder will provide a suitable test space so that reasonably accurate noise level data may be obtained

and possibly repeated at a later date. Therefore, ambient noise and reverberation

correction factors are not included.

49
29 . National Sctiool Supply and Equipment Association (NSSEA)

Purchase standards from:

National School Supply and Equipment Association

Folding Partition Subsection

1500 Wilson Boulevard

Arlington, VA 22209

29.1. Summary of Standards

29.1.1 NSSEA TEST PROCEDURE (R1972) TESTING PROCEDURES FOR MEASURING TRANSMISSION LOSS

THROUGH MOVABLE AND FOLDING WALLS.

The test procedure detailed in this booklet grew out of a long time need, on the part of school officials, architects and others, for a definitive and workable

method of comparing the sound transmission loss characteristics of movable walls.

The procedure for the test itself has been standardized by the American Society

for Testing and Materials (ASTM E90) . But it is necessary, in addition, to standardize the way the test specimen is installed, how its construction is

certified, and other details of the conduct of the test.

The test results stated in any NSSEA certificate apply to a movable wall

tested in accordance with the procedures outlined and under stated laboratory

conditions. Certification of test results will not be construed as certifying

that a movable wall of the same construction will give, under other than

laboratory conditions, identical results. For in a field installation, the

movable wall is not the only path for noise to pass from one room to the next. Other paths may be ceiling plenums, hollow floors, ventilation ducts, windows and

doors, or hollow walls.

50
30 . Power Saw Manufacturers Association (PSMA)

Purchase standards from:

Power Saw Manufacturers Association

Box 7256

Belle View Station

Alexandria, VA 22307

30.1. Summary of Standards

30.1.1 PSMA STANDARD Nl. 1,-66. NOISE LEVEL.

This Standard establishes a noise level certification procedure for measuring

the noise emitted by power saws for infrequent commercial operation in residential

areas

30.1.2 PSMA STANDARD N2.1-67. NOISE OCTAVE BAND MEASUREMENT.

This Standard establishes a test procedure for measuring noise level at the

power saw operator's ear.

51
31. Public Building Service (PBS)

Purchase standards from: , _ .

. .if;-;--

General Services Administration ... . . •

. - Public Building Service ., .

. . , - .. . Office of Construction Management

Criteria and Research Branch , . , . •,, i

-

,

• GSA Building •- =

^ ,- ; 19th and F Street, N.W. Washington, D.C. 20405 . . ,., . ^

,31.1. Summary of Standards - . . .,-.. >

31.1.1 PBS - C.l (1972) ThiS- METHOD FOR THE DIRECT MEASUREMENT OF SPEECH-PRIVACY

POTENTIAL (SPP) BASED ON SUBJECTIVE JUDGMENTS.

It is the purpose of this test method to define the Speech-Privacy Potential

and related quantities and define a method for their direct measurement or determination in a building system prototype or in the field.

31.1.2 PBS - C.2 (1972) TEST METHOD FOR THE SUFFICIENT VERIFICATION OF SPEECH-PRIVACY

POTENTIAL (SPP) BASED ON OBJECTIVE MEASUREMENTS INCLUDING METHODS FOR THE RATING

OF FUNCTIONAL INTERZONE ATTENUATION AND NC-BACKGROUND . ,, , ,.,

. , x,-.. , v,i,j

It is the purpose of this test method to define the noise Isolation Class,

the NC-Background and related Quantities, with respect to the requirements of

speech privacy in the open-plan and closed-room portions of building space, and to define methods for their direct measurement for verification of the Speech-Privacy

Potential (SPP)

.

31.1.3 PBS 4-1310 (1969) GUIDE SPECIFICATION, AUDIOMETRIC TEST ROOMS, INSTRUCTIONS FOR

USE.

This specification gives requirements for the fabrication and installation of

audiometric test rooms.

31.1.4 PBS: 4-1515-71 GUID_ SPECIFICATION, VIBRATION ISOLATION (FCGS 15140 (1972)).

This specification includes vibration isolation, equipment balancing

requirements 5 and sound level criteria for equipment spaces and exterior mounted

equipment

.

31.1.5 PBS: 4-13500 (1974) GUIDE SPECIFICATION, INTEGRATED CEILING AND BACKGROUND (ICB)

SYSTEM.

This specification gives, in addition to other requirements, acoustic

requirements for the Integrated Ceiling and Background System which includes

mechanical suspension systems, acoustical tile or lay- in panels, air terminals,

luminaries, NC Background distribution system, and necessary connection and

interface with other building elements, as required to provide lighting supply and

return of conditioned air, and other specified performance.

31.1.6 PBS: 225-lA (INT) (1964) INTERIM GUIDE SPECIFICATION, ACOUSTICAL PLASTER.

This specification gives, in addition to other installation requirements,

sound control requirements for acoustical plaster.

31.1.7 PBS: T4-10630 (1975) TENATIVE GUIDE SPECIFICATION, FREE STANDING SPACE DIVIDERS.

This tenative specification gives, in addition to other requirements,

acoustic performance requirements to be obtained by laboratory or field testing

for free standing space dividers. Two types of free standing space dividers are

52
included, (1) those which will provide speech privacy in the proper acoustical

environment, and (2) those which will only provide visual privacy but have sound

absorbing capability. This specification is to be used to procure free standing

space dividers only for those projects in which the acoustical performance

specified in PBS: 4-13500 has been provided.

31.1.8 PBS: T4-10631 (1975) TENATIVE GUIDE SPECIFICATION, FREE STANDING SPACE DIVIDERS

(ACOUSTICAL BARRIER TYPE).

This tenative specification is essentially similar to PBS : T4-10631 for

acoustical barrier type free standing space dividers. It is to be used when only

free standing space dividers which will provide speech privacy in the proper

acoustic environment are to be procured and only for those projects in which the

acoustical performance specified in PBS: 4-13500 has been provided.

31.1.9 PBS: T4-10632 (1975) TENATIVE GUIDE SPECIFICATION, FREE STANDING SPACE DIVIDERS

(VISUAL BARRIER TYPE WITH SOUND ABSORBING CAPABILITY).

This tenative specification is essentially similar to PBS : T4-10631 for

visual barrier type free standing space dividers with sound absorbing capability.

It is to be used only where a condition of speech privacy is not required or where

speech privacy cannot be achieved because of inadequate ceiling acoustical

performance specified in PBS: 4-13500.

53
32. Society of Automotive Engineers (SAE) ;

Purchase standards from:

Society of Automotive Engineers, Inc. ^

- 400 Commonwealth Drive

Warrendale, PA 15096

32.1. Summary of Standards

32.1.1 SAE J34 (1973) SAE RECOMMENDED PRACTICE, EXTERIOR SOUND LEVEL MEASUREMENT

PROCEDURE FOR PLEASURE MOTORBOATS.

This SAE Recommended Practice establishes the procedure for measuring the

maximum exterior sound level for pleasure motorboats under 65 ft (19.8 m) in

length, and describes the instrumentation, test site, and boat operation for

determining the sound level. , ... . ..

32.1.2 SAE J47 (1975) SAE RECOMMENDED PRACTICE, MAXIMUM SOUND LEVEL POTENTIAL FOR , . MOTORCYCLES

.

This SAE Recommended Practice establishes the test procedure, environment and

instrumentation for determining maximum sound level potential for motorcycles.

32.1.3 SAE J5 7 (1973) SAE RECOMMENDED PRACTICE, SOUND LEVEL OF HIGHWAY TRUCK TIRES.

This SAE Recommended Practice establishes a test procedure for measuring the

sound level produced by tires intended primarily for highway use on motor trucks,

truck tractors, trailers and semitrailers, and buses. The procedure provides for

the measurement of the sound generated by a set of test tires, mounted on the rear axle operated at 50 mph (80 km/h) and at maximum rated tire load. Specifications

for the instrumentation, the test site, and the operation of the test vehicle are

set forth to minimize the effects of extraneous sound sources and to define the

basis of reported levels.

32.1.4 SAE J88a (1975) SAE RECOMMENDED PRACTICE, EXTERIOR SOUND LEVEL MEASUREMENT ' /

' PROCEDURE FOR POWERED MOBILE CONSTRUCTION EQUIPMENT.

This SAE Recommended Practice sets forth the instrumentation and procedure to be used in measuring exterior sound levels for powered mobile construction

equipment of 20 rated bhp and over. It is not intended to cover operation of

safety devices (such as backup alarms) air compressors, jack hammers, and

machinery designed primarily for operation on highways or within factories,

aircraft, or recreational vehicles such as snowmobiles and boats. The sound

levels obtained by using the test procedures set forth in this SAE Recommended

Practice are repeatable and are representative of the higher range of sound levels

generated by the machinery under actual field operating conditions, but do not

necessarily represent the average sound level over a field use cycle.

32.1.5 SAE J184 (1972) SAE RECOMMENDED PRACTICE, QUALIFYING A SOUND DATA ACQUISITION

SYSTEM (ANSI S6. 1-1973).

Various SAE vehicle noise standards require use of a sound level meter which

meets the requirements of International Electrotechnical Commission (lEC)

Publication 179, Precision Sound Level Meters, and American National Standard

(ANSI) SI. 4-1961, Sound Level Meters. The purpose of this Recommended Practice is to provide a procedure for determining if an acoustical data acquisition system

has performance equivalent to such a meter.

I

54
32.1.6 SAE J192a (1973) SAE RECOMMENDED PRACTICE, EXTERIOR SOUND LEVEL FOR SNOWMOBILES

(ANSI S6. 2-1973)

This SAE Recommended Practice establishes the maximum exterior sound level

for snowmobiles and describes the test procedure, environment, and instrumentation

for determining this sound level.

32.1.7 SAE J331a (1975) SAE RECOMMENDED PRACTICE, SOUND LEVELS FOR MOTORCYCLES.

This SAE Recommended Practice establishes the test procedure, environment,

and instrumentation for determining sound levels typical of normal motorcycle

operation.

32.1.8 SAE J336a (1973) SAE STANDARD, SOUND LEVEL FOR TRUCK CAB INTERIOR.

This SAE Recommended Practice suggests design criteria for maximum truck cab

interior sound levels and describes the equipment and procedure for determining

this sound level. This Practice applies to new motor trucks and truck-tractors

and does not include construction and industrial machinery as outlined in SAE

J919a.

32.1.9 SAE J366b (1973) SAE STANDARD, EXTERIOR SOUND LEVEL FOR HEAVY TRUCKS AND BUSES.

This SAE Recommended Practice establishes the maximum exterior sound level

for highway motor trucks, truck-tractors, and buses, and describes the test

procedure, environment, and instrumentation for determining the maximum sound

level. The A-weighted sound level produced by trucks and buses of gross vehicle

weight over 6000 lb. shall not exceed 88 dB at a 50 foot distance when measured in

accordance with the procedure described.

32.1.10 SAE J377 (1969) SAE STANDARD, PERFORMANCE OF VEHICLE TRAFFIC HORNS. '

This SAE Standard establishes the minimum operational life cycles, corrosion

resistance, and sound level output for traffic horns (electric) on new automotive

highway vehicles. Test equipment, environment, and procedures are specified.

32.1.11 SAE J919a (1971) SAE RECOMMENDED PRACTICE, SOUND LEVEL MEASUREMENTS AT THE

OPERATOR STATION FOR AGRICULTURAL AND CONSTRUCTION EQUIPMENT.

This SAE Recommended Practice sets forth the instrumentation and procedure to be used in measuring sound levels at the operator station for agricultural and

construction equipment, including mobile outdoor industrial equipment.

32.1.12 SAE J952b (1969) SAE STANDARD, SOUND LEVELS FOR ENGINE POWERED EQUIPMENT.

This SAE Standard establishes maximum sound levels for engine powered

equipment and describes the test procedure, environment, and instrumentation for

determining these sound levels. It does not include machinery designed for

operation on highways or within factories and building areas.

32.1.13 SAE J986a (1972) SAE STANDARD, SOUND LEVEL FOR PASSENGER CARS AND LIGHT TRUCKS

(ANSI S6. 3-1973).

This SAE Standard establishes the maximum sound level for passenger cars and

light trucks and describes the test procedure, environment, and instrumentation

for determining this sound level.

32.1.14 SAE J994b (1974) SAE RECOMMENDED PRACTICE, PERFORMANCE, TEST, AND APPLICATION

CRITERIA FOR ELECTRICALLY OPERATED BACKUP ALARM DEVICES .

This SAE Recommended Practice establishes criteria for backup alarm devices on construction and mobile outdoor industrial machinery. It also establishes the

55
equipment and procedure to be used when making such measurements as well as sound

level intensity, alarm activation and mounting. The scope of construction and

industrial machinery encompasses only mobile equipment, powered by internal

combustion engines and generally utilized outside factory and building areas, such

as crawler tractors, dozers, loaders, power shovels and cranes, motor graders,

paving machines, off-highway trucks, ditchers, trenchers, compactors, scrapers,

and wagons

.

32.1.15 SAE J1046 (1974) SAE RECOMMENDED PRACTICE, EXTERIOR SOUND LEVEL MEASUREMENT

PROCEDURE FOR SMALL ENGINE POWERED EQUIPMENT.

This SAE Recommended Practice establishes the instrumentation and procedure

to be used in measuring the maximum exterior sound level for engine powered

equipment under 20 rated bhp. It is intended to include equipment such as lawn

mowers, snow blowers, tillers, etc. It is not intended to include equipment

designed primarily for operation on highways or within factories and buildings, or vehicles such as motorcycles, snowmobiles, and pleasure motor boats that are covered by other SAE Standards or Recommended Practices. This SAE Recommended ' Practice may also be used when measuring the maximum exterior sound level on similar equipment powered by electricity or other power sources.

32.1.16 SAE J1G6Q (1973) SAE RECOMMENDED PRACTICE, SUBJECTIVE RATING SCALE FOR EVALUATION

OF NOISE AND RIDE COMFORT CHARACTERISTICS RELATED TO MOTOR VEHICLE TIRES.

This SAE Recommended Practice establishes a rating scale for subjective

evaluations of noise and discomfort in motor vehicles. Through test procedures

utilizing specific vehicles on specific roads, the scale may be utilized to assess

the relative contributions of tires to noise and discomfort. The noise and ride

comfort characteristics attributed to automotive tires have traditionally been

estimated by subjectively assigning number designations (commonly on a 1 to 10

scale) to the audible and tactile sensations observed while traversing a given

road course in a vehicle equipped with the tires under evaluation. Regardless of

advances in objective measurements of tire properties related to noise and

discomfort, subjective evaluation will continue to be necessary for the purpose of

establishing the significance of such measurements. The rating scale of this

recommendation is applicable to assessment of each of the wide variety of audible

and tactile disturbances referred to by such terms as bump, thump, slap, shake, etc

.

32.1.17 SAE J1074 (1974) SAE REC0I>1MENDED PRACTICE, ENGINE SOUND LEVEL MEASUREMENT

PROCEDURE.

This SAE Recommended Practice sets forth the equipment, environment, and test procedures to be used in measuring sound levels of engines. The purpose is to provide a uniform method of measuring the maximum acoustical radiation from the

exterior surfaces of an engine under representative engine operating conditions.

The measured sound levels will be useful in development of engines, comparison of

engines, and installation of engines in various applications. The correlation of

the measured engine sound levels to the various application sound levels will have

to be developed.

32.1.18 SAE J1077 (1975) SAE RECOMMENDED PRACTICE, MEASUREMENT OF EXTERIOR SOUND LEVEL OF

TRUCKS WITH AUXILIARY EQUIPMENT.

This SAE recommended practice establishes the test procedures, environment,

and Instrumentation for determining the maximum exterior sound level of motor

truck and truck-tractor combinations wtiich are fitted with auxiliary equipment and are intended for highway operation. It is intended that the procedures are most

applicable to vehicles having a gross vehicle weight rating (GVWR) greater than

4540 kg (10,000 lbs).

56
32.1.19 SAE J1105 (1975) SAE RECOMMENDED PRACTICE, PERFORMANCE, TEST AND APPLICATION

CRITERIA OF ELECTRICALLY OPERATED FORWARD WARNING HORN FOR MOBILE CONSTRUCTION

MACHINERY.

This SAE Recommended Practice establishes criteria for electrically operated

forward warning horns on mobile construction machinery. It establishes (a)

forward warning horn performance requirements, (b) measurement technique for horn

performance requirements, (c) laboratory environmental tests and, (d) horn

activation on the vehicle.

32.1.20 SAE ARP 796 (1969) SAE AEROSPACE RECOMMENDED PRACTICE, MEASUREMENT OF AIRCRAFT

EXTERIOR NOISE IN THE FIELD.

The purpose of this Recommended Practice is to define measurement techniques

and equipment for acquisition and reduction of basic data on aircraft exterior

noise. It is not its purpose to propose use of these techniques or this equipment

for research or monitoring- type tests.

32.1.21 SAE ARP 865A(1969) SAE AEROSPACE RECOMMENDED PRACTICE, DEFINITIONS AND PROCEDURES

FOR COMPUTING THE PERCEIVED NOISE LEVEL OF AIRCRAFT NOISE.

'• - This SAE Recommended Practice gives definitions and procedures for computing

the perceived noise level of aircraft noise. The perceived noise level is a single number rating of the noise based upon objective acoustic measurements which

is related to the relative subjective response to the noise. The perceived noise

level, as defined in this document, is based only on the noise spectra measured in

octave or one- third octave bands of frequency. As such, it is most accurate in

rating broadband sounds of similar time duration which do not contain strong

discrete frequency components. When additional factors such as the duration and

the presence of discrete frequency components are to be taken into account, the

effective perceived noise level (EPNL) may be a preferred measure (see SAE ARP

1071).

32.1.22 SAE ARP 866A (1975) SAE AEROSPACE RECOMMENDED PRACTICE, STANDARD VALUES OF

ABSORPTION AS A FUNCTION OF TEMPERATURE AND HUMIDITY FOR USE IN EVALUATING

AIRCRAFT FLYOVER NOISE.

This report describes a method by which values can be obtained for the

absorption of sound in air over a wide range of temperature and humidity

conditions. Although it was developed primarily for use in evaluating aircraft

fly-over noise measurements, the information should be applicable to other noise

problems as well. There are a number of factors which influence the propagation

of aircraft noise from an aircraft flying overhead to a point on the ground. The

purpose here, however, is to consider only the classical and molecular absorption

of sound energy by the atmosphere. It is felt that spherical divergence,

scattering, refraction, and other effects should be treated separately.

32 1.23 SAE ARP 1071 (1973) SAE AEROSPACE RECOMMENDED PRACTICE, DEFINITIONS AND PROCEDURES

FOR COMPUTING THE EFFECTIVE PERCEIVED NOISE LEVEL FOR FLYOVER AIRCRAFT NOISE.

The effective perceived noise level, EPNL, specified in units of EPNdB, is a single number measure calculated from objective acoustic measurements in

accordance with the procedures defined in this document. It is calculated from a time sequence of tone-adjusted perceived noise levels which are calculated from

one-third octave band noise spectra. The tone adjustments are determined from

one-third octave band spectra, by a procedure which estimates the extent of

discrete frequency (tone) components from irregularities in the shape of the

one-third octave band noise spectra.

32.1.24 SAE ARP 1080 (1969) SAE AEROSPACE RECOMMENDED PRACTICE, FREQUENCY WEIGHTING

NETWORK FOR APPROXIMATION OF PERCEIVED NOISE LEVEL FOR AIRCRAFT NOISE.

There has been an increasing desire for the definition of a frequency

57
weighting network which could be incorporated into direct reading and other

instruments for an estimate of the Perceived Noise Level of an aircraft flyover.

This Aerospace Recommended Practice specifies a frequency weighting network (the

40-Noy noisiness contour of ARP 865A, Definitions and Procedures for Computing the

Perceived Noise Level of Aircraft Noise) may be used for the approximation of

Perceived Noise Level.

32.1.25 SAE AIR 817 (1967) SAE AEROSPACE INFORMATION REPORT, A TECHNIQUE FOR NARROW BAND

ANALYSIS OF A TRANSIENT.

This SAE Report describes a technique for analyzing a transient signal of

short duration. The standard method of analyzing tape recorded signals of only a few seconds duration is the "loop method". The magnetic tape is cut and spliced

to form an endless loop, and the loop is replayed with the aid of a tensioning

device. Difficulty arises with transient signals when the length of tape required

to make a loop covers a time over which there is a considerable variation. The

principle of the system described is that of expanding the timebase of the signal

to a point at which there is a length of tape sufficient to make a loop across which the signal is essentially constant. Although the method is one which has

been used specifically for the analysis of aircraft flyover noise, it could

equally well apply to other transient signals.

32.1.26 SAE AIR 852 (1965) SAE AEROSPACE INFORMATION REPORT, METHODS OF COMPARING AIRCRAFT

TAKEOFF AND APPROACH NOISE.

It is the purpose of this Information Report to describe a method for rating

complex aircraft noises or noise flyover cycles which cannot be handled by means

of mathematical formulae by comparing them with simpler aircraft noises or noise

flyover cycles which can be handled by mathematical formulae. The report

describes the need for an objective means for rating aircraft noise and recommends

areas which should be investigated.

32.1.27 SAE AIR 876 (1965) SAE AEROSPACE INFORMATION REPORT, JET NOISE PREDICTION.

This SAE Report provides calculation procedures for predicting maximum fly-by

noise and maximum static ground operation noise from jet aircraft. Three types of

engine exhausts are considered: (a) Turbojet with standard circular nozzle. (b)

Turbojet with nonstandard nozzle. (c) Turbofan or bypass engine with (1) unmixed

exhausts or (2) completely mixed exhausts.

Noise predictions are in terms of octave-band sound pressure levels of

maximum air-to-ground fly-by noise or of maximum ground-to-ground side-line noise.

These levels may be converted to an over-all sound pressure level or to a subjective rating such as Perceived Noise Level.

32.1.28 SAE AIR 902 (1966) SAE AEROSPACE INFORMATION REPORT, DETERMINATION OF MINIMUM

DISTANCE FROM GROUND OBSERVER TO AIRCRAFT FOR ACOUSTIC TESTS.

This SAE Report describes a photographic technique for determining minimum

observer-to-aircraft distance during acoustic "fly-over" tests. Possible sources

of error are discussed, and it is shown that with ordinary care results are sufficiently accurate to require no correction.

32.1.29 SAE AIR 923 (1966) SAE AEROSPACE INFORMATION REPORT, METHOD FOR CALCULATING THE ATTENUATION OF AIRCRAFT GROUND TO GROUND NOISE PROPAGATION DURING TAKE- OFF AND

LANDING.

The purpose of this SAE Report is to provide a standard method for predicting

the propagation of noise over open terrain from (a) an airplane on the ground to other locations on the ground and from (b) an airplane at low altitude, - i.e.,

where ground effects exist — to locations on the ground at distances which are great compared with the airplane altitude. This report provides extensive

information on what has been called the "shadow effect", i.e., attenuation

58
resulting from temperature and wind gradients near the ground. This effect is

called- "extra ground attenuation" because it is in addition to the inverse square

attenuation and the extra air attenuation.

32.1.30 SAE AIR 10 79 (1972) SAE AEROSPACE INFORMATION REPORT, AIRCRAFT NOISE RESEARCH

NEEDS

This Information Report is a classification of current aircraft noise

research needs. The areas in which research needs exist are characterized broadly

as follows: acoustics areas which have general application to a wide variety of

aircraft types and operations; specialized topics in acoustics which relate to certain aircraft or aircraft types; and areas which are not related directly to acoustics but which may play a significant role in aircraft noise alleviation.

32.1.31 SAE AIR 1081 (1971) SAE AEROSPACE INFORMATION REPORT, HOUSE NOISE-REDUCTION

MEASUREMENTS FOR USE IN STUDIES OF AIRCRAFT FLYOVER NOISE.

This AIR describes the results of some house noise reduction measurements

that were made in five locations in the U. S. in 1966, 1964, 1967, and 1969. The

houses used in these tests included a wide range of construction types of single

and multiple family dwellings. The house noise reductions also cover a wide

range. The average house noise reduction developed in this AIR should be used

only when such an average is needed. The principle objective of this AIR is to use these noise reduction measurements to develop curves showing the noise

reduction of aircraft flyover noise when the noise passes from the outside to the

inside of houses located in various climates. The noise-reduction data presented

herein can be applied to measurements of aircraft noise made outdoors in order to estimate the noise levels indoors.

32.1.32 SAE AIR 1115 (1969) SAE AEROSPACE INFORMATION REPORT, EVALUATION OF HEADPHONES FOR

DEMONSTRATION OF AIRCRAFT NOISE.

The purpose of this SAE Report is to present the results of an engineering

evaluation of commercially available headphones from the standpoints of frequency

range, flatness of response and tolerances, and dynamic range.

32.1.33 SAE AIR 1216 (1972) SAE AEROSPACE INFORMATION REPORT, COMPARISONS OF GROUND RUNUP

AND FLYOVER NOISE LEVELS.

The principal purpose of this report is to present and discuss, for each

aircraft, the differences between flyover sound pressure levels (SPL's) and SPL's

projected to comparable flyover conditions from the ground-runup measurements. A

second purpose of this report is to present the differences between ground-runup

SPL's, measured at comparable distances from the engine, over concrete and over grassy surfaces. Analyses are presented for three different engine power settings

for both types of comparisons for both airplanes.

32.2. Draft Proposals for New Standards

32.2.1 SAE XJ919b OPERATOR SOUND LEVEL MEASUREflENT PROCEDURE FOR POWERED MOBILE

EARTHMOVING AND CONSTRUCTION MACHINERY — SINGULAR TYPE TEST (To replace SAE

J919a)

32.2.2 SAE XJ1008 EXTERIOR SOUND LEVEL MEASUREMENT PROCEDURE FOR SELF-PROPELLED

AGRICULTURAL EQUIPMENT.

32.2.3 SAE XJ1030 MAXIMUM SOUND LEVEL FOR PASSENGER CARS AND LIGHT TRUCKS.

32.2.4 SAE XJ1075 MEASUREMENT PROCEDURE FOR RATING SOUND LEVEL OF CONSTRUCTION JOB SITES.

32.2.5 SAE XJ1096 MEASUREMENT OF EXTERIOR SOUND LEVEL OF HEAVY TRUCKS UNDER STATIONARY

CONDITIONS

59
32.2.6 OPERATOR SOUND LEVEL MEASUREMENT PROCEDURE FOR POWERED MOBILE EARTHMOVING AND

CONSTRUCTION MACHINERY - WORK CYCLE TEST. . .

32.2.7 RATING OF WARNING HORNS. ^

. , :

32.2.8 INTERIOR SOUND LEVEL MEASUREMENT PROCEDURE FOR PLEASURE MOTOR BOATS.

32.2.9 SOUND LEVEL MEASUREMENT PROCEDURES AT OPERATOR'S EAR FOR SNOWMOBILES.

32.2.10 OPERATOR EAR SOUND LEVEL MEASUREMENT PROCEDURE FOR SMALL ENGINE POWERED EQUIPMENT.

32.2.11 EXTERIOR AND INTERIOR SOUND LEVELS OF COACHES. '

32.2.12 EXTERIOR AND INTERIOR SOUND LEVELS OF RAIL RAPID TRANSIT VEHICLES.

32.2.13 RATING OF EXHAUST AND INDUCTION SILENCERS. ,

, ,

32.2.14 TEST PROCEDURE FOR STATIONARY MEASUREMENT OF VEHICLE EXHAUST NOISE.

32.2.15 ACOUSTICAL TERMINOLOGY AND PRESENTATION PRACTICES.

32.2.16 SAE ARP 1157 RECOMMENDED PROCEDURES FOR PRESENTING AND MEASURING AIRCRAFT NOISE IN TESTING OF HUMAN SUBJECTS.

32.2.17 SAE ARP 1158 EFFECTIVE PERCEIVED NOISE LEVEL DETERMINATION BY DIRECT SUBJECTIVE

JUDGMENT TEST.

32.2.18 SAE ARP 1264 AIRPLANE FLYOVER NOISE ANALYSIS SYSTEM USED FOR EFFECTIVE PERCEIVED

NOISE LEVEL COMPUTATIONS.

32.2.19 SAE ARP 1307 MEASUREMENT OF EXTERIOR NOISE PRODUCED BY AIRCRAFT POWER UNITS (APUs)

AND ASSOCIATED EQUIPMENT DURING GROUND OPERATION.

32.2.20 SAE ARP 1323 MEASUREMENT OF AIRCRAFT INTERIOR SOUND PRESSURE LEVELS IN FLIGHT.

32.2.21 SAE AIR 1324 THE EVALUATION OF AIRPLANE INTERIOR NOISE.

32.2.22 SAE AIR 1327 ACOUSTIC EFFECTS PRODUCED BY A REFLECTING PLANE.

32.2.23 PREDICTION FOR NEAR-FIELD AND FAR-FIELD PROPELLOR NOISE.

32.2.24 PREDICTION OF NOISE FROM BLOWN FLAPS FOR STOL AIRCRAFT.

32.2.25 METHODS TO ACCOUNT FOR THE EFFECTS OF GROUND REFLECTIONS ON ACOUSTIC MEASUREMENT.

60
33 . Steel Door Institute (SDI)

Purchase standards from:

Steel Door Institute

2130 Keith Building

Cleveland, OH 44115 ' •'

33.1. Summary of Standards

33.1.1 SDI 114 (1972) STANDARD ACOUSTICAL PERFORMANCE TEST FOR STEEL DOOR AND FRAME

ASSEMBLIES.

The primary purpose of this procedure is to establish minimum standards and

methods of testing the effectiveness of steel door and frame assemblies under

circumstances that might remotely be considered normal field applications and

conditions.

61
34 . Woodworking Machinery Manufacturers Association (WMMA)

Purchase standards from: '

- • , " .,.() j

.

Woodworking Machinery Manufacturers Association

1900 Arch Street \ Philadelphia, PA 19103

34.1. Summary of Standards

34.1.1 WMMA TEST CODE (1973) TEST CODE FOR EVALUATING THE NOISE EMISSION OF WOODWORKING

MACHINERY.

This document establishes a test code for evaluating noise emissions of

woodworking machinery. It entails the definition of the terminology to be

employed; delineation of a machine classification index; and specifies test

conditions, operating conditions, measuring instrximents , methods of measurements

and procedures for reporting test data.

62
Appendix A. Summary of Federal Regulations

A.l DEPARTMENT OF LABOR OCCUPATIONAL NOISE EXPOSURE STANDARD, TITLE 29, CODE OF

FEDERAL REGULATIONS, CHAPTER XVII, PART 1910, SUBPART G, 36 FR 10466, MAY 29,

1971.

The Department of Labor's noise exposure standard first was promulgated under

the Walsh-Healey Public Contracts Act. It was adopted under the Occupational

Safety and Health Act on May 29, 1971, and is applicable under the general

industry, construction, and longshore standards. It provides for protection

against the effects of noise exposure. The combined effects of the amount of

exposure at different sound levels are used to determine the maximum exposure

permitted. When these permissible exposure limits are exceeded, feasible

administrative (including a continuing hearing conservation program) and/or

engineering controls must be implemented. See Table below.

PERMISSIBLE NOISE EXPOSURES^^

Sound

Duration per level

day, hours dBA slow

8 90

6 92

4 95

3 97

2 100

1 1/2 102

1 105

1/2 110

1/4 or less 115 — When the daily noise exposure is composed of two or more

periods of noise exposure at different levels, their com- bined effect should be considered, rather than the individual

effect of each. If the sum of the following fractions:

Cl/T. + C2/T2 .... Cn/Tn exceeds unity, then, the mixed

exposure should be considered to exceed the limit value. Cn

indicates the total time of exposure at a specified noise level,

and Tn indicates the total time of exposure permitted at that

level

A. 2 DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CIRCULAR 1390.2, NOISE ABATEMENT AND

CONTROL: DEPARTMENTAL POLICY, IMPLEMENTATION RESPONSIBILITIES AND STANDARDS,

AUGUST 4, 1971.

This HUD circular requires that noise exposures and sources of noise be given

adequate consideration as an integral part of urban environments in connection

with all HUD programs which provide financial support to planning. This

consideration is to be of a form that provides assurance that new housing and

other noise sensitive accommodations will not be planned for areas whose current

or projected noise exposures exceed the standards cited in this circular.

The basic requirements are given in the following chart:

63
EXTERNAL NOISE EXPOSURE STANDARDS FOR NEW CONSTRUCTION SITES

(Measurements and projections of noise exposures are to be made at appropriate heights above site boundaries.)

GENERAL EXTERNAL EXPOSURES AIRPORT ENVIRONS

dB (A) CNR ZONE */ NEF ZONE */

UNACCEPTABLE

Exceeds 80 dB(A) 60 minutes 3 C per 24 hours

Exceeds 7 5 dB(A) 8 hours

per 24 hours

(Exceptions are strongly discouraged and require a 102(2)C.

environmental statement and the Secretary's approval)

DISCRETIONARY ~ NORMALLY UNACCEPTABLE

Exceeds 65 dB(A) 8 hours per 2 B

24 hours

Loud repetitive sounds on site

(Approvals require noise attenuation measures, the Regional

Administrator's concurrence and a 102(2) C environmental

statement)

DISCRETIONARY — NORMALLY ACCEPTABLE

Does not exceed 65 dB(A) more than

8 hours per 24 hours

ACCEPTABLE

Does not exceed 45 dB(A) more than 1 A

30 minutes per 24 hours

for explanations of Composite Noise Rating (CNR) and

Forecast (NEF). — See Appendix 2 Noise Exposure

64
A. 3 DEPARTMENT OF THE INTERIOR NOISE STANDARD ISSUED UNDER THE FEDERAL COAL MINE

HEALTH AND SAFETY ACT, TITLE 30, CODE OF FEDERAL REGULATIONS, CHAPTER I, PARTS 70 AND 71, 35 FR 5544, APRIL 3, 1970; 36 FR 12739, JULY 7, 3971; 37 FR 6368, MARCH

28, 1972; 38 FR 18666, JULY 13, 1973.

This standard is essentially similar to the Department of Labor Noise

Exposure Standard (see A.l).

A. 4 GENERAL SERVICES ADMINISTRATION, PUBLIC BUILDINGS SERVICE CONSTRUCTION EQUIPMENT

AND PRACTICES, PAR. 44.8 IN GUIDE SPECIFICATION PBS 4-01100, OCTOBER 1973.

This regulation sets maximum permissible noise emission levels for

construction equipment. These levels are given in the following table:

MAXIMUM PERMISSIBLE NOISE EMISSION LEVELS AT 50 FEET

Effective Dates ; .

Equipment July 1, 1972 January 1, 1975

Earthmoving

front loader

backhoes

dozers

tractors

scrapers

graders

truck

paver

Materials Handling

concrete mixer 85 ' ' 7'5 concrete pump , 82 ,

• : , 7.5 crane 83 ' 75, derrick ^ v ^. - 88. • - • V - '.•

. 75

79 '" ''"'^^ '

' .

: 85 75

80 75

80 ' • 75' " 88 . , 80 . 85 . ^ ; V .

' ys"- -. 91 ' •

• ^''tS'-'' 89 - . V : 80 '-

.

Stationary

pumps 76 75

generators 78 . . ^ . .75

compressors 81 ', \ , 75;

Impact

pile drivers 101 95

jack hammers 88 ' ;-7S rock drills 98 ;

• . • "

,.

. 80

pneumatic tools 86 80

Other

saws 78 75

vibrators 76 75

A. 5 FEDERAL AVIATION ADMINISTRATION NOISE STANDARDS, TITLE 14, CODE OF FEDERAL

REGULATIONS, CHAPTER I, PART 36, 34 FR 1864, NOVEMBER 18, 1969, AS AMENDED AT 38 FR 29574, OCTOBER 26, 1973.

This standard outlines procedures for the measurement of aircraft noise

emissions as received on the ground. One section is reserved for setting noise

limits (not yet specified) for certain aircraft. Noise levels for subsonic

transport category and turbojet powered airplanes are given. They are:

65
(1) For approach and sideline, 108 EPNdB for maximum weigt;ts of 600,000

pounds or more, less 2 EPNdB per halving of the 600,000-pound maxi-um weight down

to 102 EPNdB for maximum weights of 7 5,000 pounds and under.

(2) For takeoff, 108 EPNdB for maximum weights of 600,000 pounds or more,

less 5 EPNdB per halving of the 600,000-pound maximum weight down to 93 EPNdB for

maximum weights of 75,000 pounds and under.

A. 6 DEPARTMENT OF TRANSPORTATION, FEDERAL HIGHWAY ADMINISTRATION VEHICLE INTERIOR

NOISE LEVELS, TITLE 49, CODE OF FEDERAL REGULATIONS, CHAPTER III, SUBCHAPTER B,

PART 393.94, 38 FR 30880, NOVEMBER 8, 1973.

This regulation specifies motor carrier safety regulations for noise. The

interior sound level of motor vehicles must not exceed an A-weighted sound level

of 90 decibels as measured by a microphone located six inches to the right of and

in the same plane as the driver's right ear. Vehicle operation is as follows:

transmission in neutral gear and the engine at maximum governed speed (or if the

engine is not equipped with an engine governor, at the speed corresponding to maximum rated horsepower.

A. 7 DEPARTMENT OF TRANSPORTATION, FEDERAL HIGHWAY ADMINISTRATION HIGHWAY NOISE CONTROL

STANDARDS AND PROCEDURES, TITLE 23, CODE OF FEDERAL REGULATIONS, CHAPTER I, SUBCHAPTER J, PART 772, 38 FR 15953, JUNE 19, 1973, AS AMMENDED AT 39 FR 6696,

FEBRUARY 22, 1974.

This regulation provides noise standards and procedures for use by State

highway agencies and the Federal Highway Administration (FHWA) in the planning and

design of highways approved pursuant to title 23, United States Code, and to assure that measures are taken in the overall public interest to achieve highway

noise levels that are compatible with different land uses, with due consideration

also given to other social, economic and environmental effects. See Table.

DESIGN NOISE LEVEL/LAND USE RELATIONSHIPS

Land use Design noise level - L^ Description of land use category

dBA

A 60 (Exterior) Tracts of lands in which serenity and quiet are of

extraordinary significance and serve an important

public need, and where the preservation of those

qualities is essential if the area is to continue

to serve its intended purpose. Such areas could

include amphitheaters, particular parks or portions

of parks, or open spaces which are dedicated or recognized by appropriate local officials for

activities requiring special qualities of serenity

and quiet.

B 70 (Exterior) Residences, motels, hotels, public meeting rooms, schools, churches, libraries, hospitals, picnic

areas, recreation areas, playgrounds, active sports

areas, and parks.

C 75 (Exterior) Developed lands, properties or activities not included in categories A and B of this subparagraph.

D For requirements on undeveloped lands see 772.5(a)

(5) and (6).

E 55 (Interior) Residences, motels, hotels, public meeting rooms, schools, chxirches, libraries, hospitals, and

auditoriums

.

66
A. 8 CERTIFICATION PROCEDURES FOR LOW-NOISE-EMISSION PRODUCTS, TITLE 40, CODE OF

FEDERAL REGULATIONS, PARTS 203.0 - 203.8, 39 FR 6670, FEBRUARY 21, 1974, AS

CORRECTED AT 39 FR 7 930, MARCH 1, 1974, EFFECTIVE MARCH 25, 1974.

This regulation prescribes procedures for the certification of

low-noise-emission products. It does not contain the low-noise-emission criterion

nor does it contain the specific data requirements necessary for deciding whether

a product is a "suitable substitute." These will be published later.

A. 9 ENVIRONMENTAL PROTECTION AGENCY FINAL NOISE EMISSION STANDARDS, MOTOR CARRIERS

ENGAGED IN INTERSTATE COMMERCE, TITLE 40, CODE OF FEDERAL REGULATIONS, CHAPTER I, PART 202, 39 FR 38208, OCTOBER 29, 1974.

This regulation establishes final noise emission standards for motor carriers

(whose gross vehicle weight or gross combination weight is in excess of 10,000

pounds) engaged in interstate commerce. The regulations stipulate the following

allowable A-weighted noise levels:

1) At vehicle speeds of 35 mph or less under any operational condition —

88 dB.

2) At vehicle speeds in excess of 35 mph under any operational condition —

92 dB.

3) Stationary maximum acceleration — 88 dB.

These limits are for a hard surfaced test site for measurements made 50 feet

from the centerline of the vehicle. Allowable limits are also prescribed for

alternate measurement distances and for soft surfaced test sites.

i

67
Appendix B. Commit tees /Technical Contacts

1 . Acoustical and Board Products Association (ABPA)

(formerly Acoustical and Insulating Materials Association (AIMA)

1.1 Technical Committee on Acoustical Material

Technical Contact

R. A. LaCosse

Acoustical and Board Products Association

205 West Touhy Avenue

Park Ridge, IL 60068

2 . Acoustical Society of America (ASA)

2.1 ASA Committee on Standards (ASACOS)

Chairman

H. E. von Gierke

Aerospace Medical Research Lab.

Wright Patterson AFB

Dayton, OH 45433

3 . Air Conditioning and Refrigeration Institute (ARI)

3.1 Technical Committee on Sound

Chairman

R. W. Ramsey

Heil-Quaker Corp.

Subsidiary of Whirlpool

647 Thompson Lane

Nashville, TN 37204

4 . Air Diffusion Council (ADC)

4.1 No active committees at present.

Technical Contact

G. Otto

Air Diffusion Council

435 North Michigan Ave.

Chicago, IL 60611

68
5 . Air Moving and Conditioning Association (AMCA)

5.1 Technical Advisory Committee on Sound

Technx^ax Contact

K. W. Burkhardt

Technical Direcuor

Air Moving and Conditioning Association

30 West niversity Drive

Arlington Heights, IL 60004

6 . American Gear Manufacturers Association (AGMA)

6.1 Acoustical Technology Committee

Chairman

W. B adley

hiladelphia Gear Works

King of Prussia, PA 19406

7 . American National Standards Institute (ANSI)

7.1 ANSI SI Acoustics

Chairman

E. E. Gross

General Radio Co. 300 Baker Ave.

Concord, A 01742

7.2 ANSI S3 Bioacoustics .

"

Chairman

W. Melnick

Ohio State University

College of Medicine

Dept. of Otolaryngology

3024 University Hospital Clinic

456 Clinic Drive

Columbus, OH 43210

8 . American Society of Heating, Refrigerating, and

Air Conditioning Engineers (ASHRAE)

8.1 2.6 Sound and Vibration Technical Committee

Technical Contact

N. A. LaCourte

American Society of Heating, Refrigerating, and Air Conditioning Engineers

345 E. 47th St. New York, NY 10017

69
9 . American Society for Testing and Materials (ASTM)

9.1 ASTM E-33 Environmental Acoustics . ,

Chairman

H. F. Kingsbury

Pennsylvania State University

University Park, PA 16801

10. American Textile Machinery Association (ATMA)

10.1 No active committees at present.

Technical Contact

W. Beckwith

Leesona Corp

.

Warwick, RI 02887

11 . Anti-Friction Bearing Manufacturers Association (AFBMA)

11.1 Sub-Committee on Vibration and Noise

Chairman

J. C. Morrison

Barden Corp.

200 Park Ave.

Danbury, CT 06810

12 . Association of Home Appliance Manufacturers (AHAM)

12.1 AHAM Room Air-Conditioner Sound Sub-Committee

Chairman

R. W. Gilmer

Chrysler Corporation

1600 Webster Street

P. 0. Box 1037

Dayton, OH 45404

Technical Consultant to Engineering Standards Committee

M. Naake

General Electric

Major Appliance Business Group

Appliance Park

Louisville, KY 40225

70
13. Compressed Air and Gas Institute (CAGI)

't 13.1 No active committees at present.

Technical Contact

A. P. Wherry , . ^ : Secretary-Treasurer ..

. : _

.-. .. : _.•}•. Compressed Air and Gas Institute '' - ' -

' 2130 Keith Bldg. '.

' Cleveland, OH 44115 , ;.

14. Diesel Engine Manufacturers Association (DEMA) ""'

14.1 No active committees at present.

Technical Contact

A. P. Wherry

Secretary-Treasurer

Diesel Engine Manufacturers Association

2130 Keith Bldg.

Cleveland, OH 44115

15 . Electronic Industries Association (EIA)

15.1 Electroacoustic Committee

Chairman ~

P. B. Williams

Rapid Die Molding Co. Chiller Park, IL 60176 -u" -.y^^ • ^'yf^^•r:'^¥::

'Vi^. Federal Construction Guide Specification (FCGS)

16.1 No active committees at present.

Technical Contact ' -

M. Borger

Executive Secretary

Building Research Advisory Board

Federal Construction Council

2101 Constitution Avenue, N.W. Washington, DC 20418

17.1

17 . Federal Specifications

No active committees at present.

Information

Specification Sales (3FRDS)

Building 197, Washington Navy Yard

General Services Administration

Washington, D. C. 20407

71
18. Home Ventilating Institute (HVI)

18.1 Sound Subcommittee of Engineering Committee

Technical Contact

D. McClurg

Associate Director

Home Ventilating Institute

2 30 North Michigan Ave.

Chicago, IL 60601

19 . Industrial Silencer Manufacturers Association (ISMA)

19.1 No active committees at present.

Technical Contact

R. J. Yeager, ISMA

c/o Burgess Industries

P. 0. Box 47146

Dallas, TX 75247

20. Institute of Electrical and Electronic Engineers (IEEE)

20.1 Acoustical Speech and Signal Processing Standards Committee

Chairman

H. R. Silbiger

Bell Laboratories

3E Corner Crawfords Road 511

Holmdel, NJ 07733

21. Instrument Society of America (ISA)

21.1 No active committees at present.

Technical Contact

R. G. Hand

Manager, Publications, Education and Standards

Instrument Society of America

400 Stanwix Street

Pittsburgh, PA 15222

22. International Conference of Building Officials (ICBO)

22.1 No active committees at present.

Technical Contact

D. R. Watson

Technical Director

International Conference of Building Officials

5360 South Workman Mill Road

Whittier, California 90601

72
23 . International Electrotechnlcal Commission (lEC)

23.1 lEC/TC 29 TEC Technical Committee on Electroacoustics

Chairman

W, W. Lang • IBM Acoustics Lab, Bldg. 704

P. 0. Box 390

Poughkeepsie, NY 16203

23.2 lEC/TC 29/SC 29C Measuring Devices

U. S. Technical Advisory Group

ANSI SI Acoustics .'

. . ANSI S2 Mechanical Shock and Vibration

ANSI S3 Bioacoustics 'v^

U. S. Technical Advisor

W. R. Kundert . .

' General Radio Co

300 Baker Ave. Concord, MA 01742 ....

24 , International Organization for Standardization (ISO)

24.1 ISO/TC 43/SC 1 Noise '

' \

' '

'

U. S. Technical Advisory Group

ANSI SI Acoustics • •

. ,. ANSI S3 Bioacoustics -

'

.

U. S. Technical Advisor

L. Batchelder . . .. 983 Memorial Drive

Cambridge, MA 02138

24.2 ISO/TC 43/SC 2 Building Acoustics

U. S. Technical Advisory Group

ASTM E 33 Environmental Acoustics

U. S. Technical Advisor

Vacant

25. Military Specifications

25.1 No active committees at present.

Information

Commanding Officer

Naval Publications and Forms Center

5801 Tabor Ave.

Philadelphia, PA 19120

73
26 . National Electrical Manufacturers Association (NEMA)

26.1 No active committees at present. •

. .

Technical Contact • •

Ms. V. Morgan

National Electrical Manufacturers Association

155 East 44th Street :' New York, NY 10017 , / /.

27 . National Fluid Power Association (NFPA)

27.1 Sound Measurement Coordinating Committee _

^

Chairman • .

•

G. Czarnecki

DeLavel

IMG Pump Division

P.O. Box 321 ,

. .

;

Trenton, NJ 08602

28 . National Machine Tool Builders Association (NMBTA)

28.1 No active committees at present.

Technical Contact '

•

W. Atkinson, Jr. ' ' Safety Director

National Machine Tool Builders Association '.' " 7901 West Park Drive

McLean, VA 22101 '

; "

'

29. National School Supply and Equipment Association (NSSEA

29.1 No active committees at present.

Technical Contact

National School Supply and Equipment Association

1500 Wilson Blvd.

Arlington, VA 22209

30. Power Saw Manufacturers Association (PSMA) ; •' • .'"

30.1 No active committees at present. v

Technical Contact .'

'

J. W. Cawthorne ' ' Power Saw Manufacturers Association •" ' > Box 7256

Belle View Station

Alexandria, VA 22307

74
31. Public Building Service (PBS)

31.1 No active committees at present.

Technical Contact

J. Parker

Office of Construction Management • ;• , ' '

Criteria and Research Branch . > Rm. 3306 GSA Bldg.

19th and F Street, N.W. Washington, DC 20405

32 . Society of Automotive Engineers CSAE)

32.1 SAE Committee A-21, Aircraft Noise Measurement

Chairman

F. W. Kolk

American Airlines, Inc. 633 Third Ave.

New York, NY

32.2 SAE Vehicle Sound Level Committee ;. : '

Chairman - : _

R. K. Hillquist

Project Manager

Noise and Vibration Laboratory

GM Proving Ground

Milford, MI 48042 . - . • • >• •

:

•

32.3 SAE Off-Road Sound Level Committee

Chairman , , ;. :.

J. M. Mohr ..

'

' Director of Research ,

.•, Outboard Marine Corp.

P. 0. Box 663

Milwaukee, WI 53201

33. Steel Door Institute (SDI)

33.1 No active committees at present. •

Technical Contact

A. P. Wherry

Secretary-Treasurer

Steel Door Institute

1230 Keith Building

Cleveland, OH 44115

75
34 . Woodworking Machinery Manufacturers Association (WMMA)

34.1 No active committees at present.

Technical Contact

D. White

Woodworking Machinery Manufacturers Association

1900 Arch Street

Philadelphia, PA 19103

76 ftU.S. GOVERNMENT PRINTING OFFICE: 1976 210-801/207 1-3
NBS-114A (REV. 7-73)

U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBSSP-386, 19 7 6 edition

2. Gov't Accession

No.

4. TITLE AND SUBTITLE

Standards on Noise Measurements, Rating Schemes,

and Definitions: A Compilation

3. Recipient's Accession No.

5. Publication Date April 1976

7. AUTHOR(S)

Thomas L. Quindry, Editor

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

2. Sponsoring Organization Name and Complete Address (Street. City, State, ZIP)

Same as No, 9,

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IL Contract/Grant No.

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Library of Congress Catalo g Card Number: 73- 600305

16. ABSTRACT (A 200-word or less factual summary ol most sigr^ificant information. If document includes a significant

bibliograpyiy or literature survey, mention it here.) This compilation deals with material assembled from the various standards, industrial

and trade organizations, or technical and scientific societies concerned with acoustics.

There has been no attempt to review or evaluate the standards, but rather just to list

documents covering measurement techniques, calibration methods, definitions^ rating

schemes, and equipment and product specifications concerned with noise. Those standards

dealing solely with ultrasonics, audio equipment, or shock and vibration have not

generally been included. The paragraphs describing the standards give a brief summary

of intent and/or scope of the standard. In some cases the paragraph is the official

description of the standard as issued by the organization or society promulgating the

standard, while in others the paragraph merely describes the intent of the standard.

Proposed standards are also listed where available. Not listed are proposed revisions

of current standards and those which must be reapproved to remain in effect. For the

convenience of those readers wishing to purchase copies of standards, names and addresses

for the various organizations and/or societies are provided. Federal Regulations

directly involving noise measurements are given in Appendix A. Appendix B lists active

committees for each organization and names and addresses of appropriate committee

chairmen or technical contacts. This compilation includes all information available as

of January 1, 1976.

17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only the first letter of the first key word unless a proper

name; separated by semicolons

)

Acoustics; noise; rating scheme; sound; standards organization.

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