1、BRITISH STANDARD BS EN 24869-1:1993 ISO 4869-1: 1990 Incorporating Amendment No. 1 Sound attenuation of hearing protectors Part 1: Subjective method of measurement The European Standard EN 24869-1:1992 has the status of a British Standard UDC 614.892:620.1:534.61:534.833.5BSEN24869-1:1993 This Briti
2、sh Standard, having been prepared under the directionof the Environment andPollution Standards Policy Committee, was published underthe authority of the Standards Board and comes intoeffect on 28 June 1991 BSI 08-1999 First published July 1974 Second edition September 1983 Third edition June 1991 Th
3、e following BSI references relate to the work on this standard: Committee reference EPC/1 Draft announced in BSI News July1989 ISBN 0 580 19628 3 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Environment and Pollution Standards Policy
4、Committee (EPC/-) to Technical Committee EPC/1, upon which the following bodies were represented: Association of Consulting Engineers British Broadcasting Corporation British Occupational Hygiene Society British Telecommunications plc Department of Health Department of the Environment (Building Rese
5、arch Establishment) Department of Trade and Industry (Air Division) Department of Trade and Industry (National Physical Laboratory) Engineering Equipment and Materials Users Association Health and Safety Executive Incorporated Association of Architects and Surveyors Institute of Acoustics Institute
6、of Occupational Hygienists Institute of Physics Institute of Sound and Vibration Research Institution of Civil Engineers Institution of Electrical Engineers Royal Institute of British Architects Society of Environmental Engineers Transmission and Distribution Association (BEAMA Ltd.) The following b
7、odies were also represented in the drafting of the standard, through subcommittees and panels: Electricity Supply Industry in UK Industrial Safety (Protective Equipment) Manufacturers Association Institution of Mechancial Engineers Ministry of Defence Society of Hearing Aid Audiologists Ltd. Univers
8、ity of Salford Amendments issued since publication Amd. No. Date Comments 7552 February 1993 Indicated by a sideline in the marginBSEN24869-1:1993 BSI 08-1999 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3
9、4 Measurement of the sound attenuation of hearing protectors 4 Annex A (informative) Uncertainty of sound attenuation measurements 8 Annex B (informative) Bibliography 8 Table 1 Allowable field variation for different microphones 5 Table 2 Maximum permissible background sound pressure level 5 Table
10、3 Minimum and maximum sound pressure levels for test signals 5 Table A.1 Repeatability and reproducibility of sound attenuation measurements on ear-muffs at a probability level of 95% (according to ISO 5725) 8 Table A.2 Repeatability and reproducibility of sound attenuation measurements on ear-plugs
11、 at a probability level of 95% (according to ISO 5725) 8 Publication(s) referred to Inside back coverBSEN24869-1:1993 ii BSI 08-1999 National foreword This Part of BS 5108 has been prepared under the direction of the Environment and Pollution Standards Policy Committee. It is identical with ISO 4869
12、-1:1990 “Acoustics Hearing protectors Part 1: Subjective method for the measurement of sound attenuation”, published by the International Organization for Standardization (ISO). ISO4869-1 was prepared by Subcommittee 1, Noise, of ISO Technical Committee 43, Acoustics, with the active participation a
13、nd approval of the UK. It constitutes a minor revision of ISO4869:1981. In 1992 the European Committee for Standardization (CEN) accepted ISO 4869-1:1990 as European Standard EN 24869-1:1992. As a consequence of implementing the European Standard this British Standard is renumbered as BSEN24869-1 an
14、d any reference to BS 5108-1:1991 should be read as a reference to BS EN24869-1. This Part of BS 5108 is a revision of BS 5108:1983, which is withdrawn. Further revised Parts of BS5108 are in preparation. A second Part will be based on ISO4869-2 “Estimated noise reduction of hearing protectors” and
15、a third Part is envisaged, based on a future revision of ISO/TR 4869-3:1989 “Simplified method for the measurement of insertion loss of ear-muff type protectors for quality inspection purposes” which was implemented, dual-numbered as DD192:1990. Hearing protectors are commonly used to reduce the noi
16、se to which the ear is exposed. Hearing protectors are manufactured as ear-plugs, ear-muffs or helmets. A standardized method of sound attenuation measurement allows performance data obtained in different locations under similar conditions to be compared. The data may be used for rank ordering and s
17、election of different models and the evaluation of design and construction features that affect performance. Cross-references International Standard Corresponding British Standard ISO 354:1985 BS 3638:1987 Method for measurement of sound absorption in a reverberation room (Identical) ISO 389:1985 BS
18、 2497 Standard reference zero for the calibration of pure tone air conduction audiometers Part 5:1988 Specification for a standard reference zero using an acoustic coupler complying with BS 4688 (Identical) ISO 5725:1986 BS 5497 Precision of test methods Part 1:1987 Guide for the determination of re
19、peatibility and reproducibility for a standard test method by inter-laboratory tests (Identical) ISO 6189:1983 BS 6655:1986 Specification for pure tone air conduction threshold audiometry for hearing conservation purposes (Identical) IEC 225:1966 BS 2475:1964 Specification for octave and one-third o
20、ctave band-pass filters (Technically equivalent) IEC 263:1982 BS 6397:1983 Specification for scales and sizes for plotting frequency characteristics and polar diagrams (Identical)BSEN24869-1:1993 BSI 08-1999 iii The Technical Committee has reviewed the provisions of ISO8253-2, to which reference is
21、made in clause2 and 4.5.5 and in a note to 3.7, and of the draft of IEC645-1, to which reference is made in clause 2 and 4.3.4, and has decided that they are acceptable for use in conjunction with this standard. ISO 8253-1, to which reference is made in a note to 3.6 and in the informative bibliogra
22、phy, is given for information only and does not affect the use of this Part of BS5108. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of i
23、tself confer immunity from legal obligations. International Standard Corresponding British Standard IEC 651:1979 BS 5969:1981 Specification for sound level meters (Identical) IEC 804:1985 BS 6698:1986 Specification for integrating-averaging sound level meters (Identical) Summary of pages This docume
24、nt comprises a front cover, an inside front cover, pages i to iv, theENtitle page, pages 2 to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cove
25、r.iv blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 24869-1 October 1992 UDC 614.892:620.1:534.61:534.833.5 Descriptors: Acoustics, ear protectors, acoustic measurement, noise reduction English version Acoustics Hearing protectors Subjective method for the measurement of sound attenuation
26、 (ISO 4869-1:1990) Acoustique Protecteurs individuels contre le bruit Mthode subjective de mesurage de laffaiblissement acoustique (ISO 4869-1:1990) Akustik Gehrschtzer Subjektive Methode zur Messung der Schalldmmung (ISO 4869-1:1990) This European Standard was approved by CEN on 1992-10-16. CEN mem
27、bers are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on applicat
28、ion to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the
29、same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardiz
30、ation Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1992 Copyright reserved to CEN members Ref. No. EN 24869-1:1992 EEN24869-1:1992 BSI 08-1999 2 Foreword This European Standard is the endorsement of ISO4869-1. Endorsement of I
31、SO 4869-1 was recommended by Technical Committee CEN/TC 211 “Acoustics” under whose competence this European Standard will henceforth fall. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by April 19
32、93, and conflicting national standards shall be withdrawn at the latest by April 1993. The Standard was approved and in accordance with the CEN/CENELEC Internal Regulations the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Gre
33、ece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, UnitedKingdom.EN24869-1:1992 BSI 08-1999 3 1 Scope This International Standard specifies a subjective method for measuring sound attenuation of hearing protectors at the threshold of hearing. The met
34、hod and procedures are designed to yield values close to the maximum attenuation which are not normally attained under field conditions. This approach has been adopted because the attenuation values can then be consistently reproduced. The values reflect the attenuating characteristics of the hearin
35、g protector only to the extent that users wear the device in the same manner as did the test subjects. This test method yields data which are collected at low sound pressure levels (close to the threshold of hearing) but which are also representative of the attenuation values of hearing protectors a
36、t higher sound pressure levels. An exception occurs in the case of amplitude-sensitive hearing protectors for sound pressure levels above the point at which their level-dependent characteristics become effective. At those sound pressure levels the method specified in this International Standard is i
37、napplicable; it will usually underestimate sound attenuation for these devices. NOTE 1At low frequencies (below500Hz) the sound attenuation may be overestimated by a few decibels as a result of masking the occluded ear thresholds caused by physiological noise during the occluded ear tests. 2 Normati
38、ve references The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO 4869. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO 48
39、69 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 354:1985, Acoustics Measurement of sound absorption in a reverberation room. ISO 8253-2:,
40、Acoustics Audiometric test methods Part 2: Sound field audiometry with pure tone and narrow-band test signals 1) . IEC 225:1966, Octave, half-octave and third-octave band filters intended for the analysis of sounds and vibrations. IEC 263:1982, Scales and sizes for plotting frequency characteristics
41、 and polar diagrams. IEC 645-1:, Audiometers Part 1: Pure tone audiometers 2) . IEC 651:1979, Sound level meters. IEC 804:1985, Integrating-averaging sound level meters. 3 Definitions For the purposes of this part of ISO 4869, the following definitions apply. 3.1 hearing protector a device worn by a
42、 person to prevent unwanted auditory effects from acoustic stimuli NOTE 2Hearing protectors may include electronic devices for communication or devices designed to play an active role in the reduction of the noise level between the hearing protector and the ear-drum. 3.2 ear-muff a hearing protector
43、 consisting of an ear-cup to be pressed against each pinna or of a circumaural ear-cup to be pressed against the head around the pinna. The ear-cups can be pressed against the head with a special headband or neck-band or by means of a device attached to a safety helmet or other equipment 3.3 ear-plu
44、g a hearing protector worn within the external ear canal (aural) or in the concha against the entrance to the external ear canal (semi-aural) 3.4 helmet a device which covers a substantial part of the head 3.5 hearing level (of a pure tone) at a specified frequency, for a specified type of earphone
45、and for a specified manner of application, the sound pressure level of this pure tone produced by the earphone in a specified acoustic coupler or artificial ear minus the appropriate reference equivalent threshold sound pressure level NOTE 3Values of reference equivalent threshold sound pressure lev
46、els are specified in ISO389. 3.6 hearing threshold level (of a given ear) at a specified frequency and for a specified type of earphone, the threshold of hearing expressed as hearing level NOTE 4For appropriate test conditions see, for example, ISO6189 and ISO8253-1. 1) To be published. 2) To be pub
47、lished. (Revision of IEC 645:1979.)EN24869-1:1992 4 BSI 08-1999 3.7 threshold of hearing the lowest sound pressure level at which, under specified conditions, a person gives a predetermined percentage of correct detection responses on repeated trials NOTE 5For the purpose of this International Stand
48、ard, the threshold of hearing is measured with and without the hearing protector. For appropriate test conditions, see ISO8253-2. 3.8 sound attenuation for a given test signal, the difference, in decibels, between the threshold of hearing with and without the hearing protector in place for a test su
49、bject 3.9 pink noise noise the sound pressure spectral density of which is inversely proportional to frequency 3.10 reference point the midpoint of a line connecting the test subjects ear canal openings 3.11 reverberation time the time required for the sound pressure level to decrease by60dB after the sound source has stopped (see ISO354) 3.12 repeatability the value below which the absolute difference between two single test results obtained with the same method on identical test material, under the same conditions (same opera
