DIN EN ISO 4869-3-2007 Acoustics - Hearing protectors - Part 3 Measurement of insertion loss of ear-muff type protectors using an acoustic test fixture (ISO 4869-3 2007) English ve.pdf

1、September 2007DEUTSCHE NORM English price group 11No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 13.340.20!$I7$“13820

2、01www.din.deDDIN EN ISO 4869-3Acoustics Hearing protectors Part 3: Measurement of insertion loss of ear-muff type protectors usingan acoustic test fixture (ISO 4869-3:2007)English version of DIN EN ISO 4869-3:2007-09Akustik Gehrschtzer Teil 3: Messung der Schalldmmung von Kapselgehrschtzern unter Ve

3、rwendung einerakustischen Prfvorrichtung (ISO 4869-3:2007)Englische Fassung DIN EN ISO 4869-3:2007-09SupersedesDIN EN 24869-3:1994-02www.beuth.de11.07Document comprises 19 pages DIN EN ISO 4869-3:2007-09 2 National foreword This standard has been prepared by Technical Committee ISO/TC 43 “Acoustics”

4、 in collaboration with Technical Committee CEN/TC 211 “Acoustics” (Secretariat: DS, Denmark). The responsible German body involved in its preparation was the Normenausschuss Akustik, Lrmminderung und Schwingungstechnik (Acoustics, Noise Control and Vibration Engineering Standards Committee in DIN an

5、d VDI), Technical Committee NA 001-01-06 AA Messung der Schalldmmung von Gehrschtzern. The DIN Standards corresponding to the International Standards referred to in clause 2 of the EN are as follows: ISO 48 DIN ISO 48 ISO 4869-1 DIN ISO 4869-1 IEC 60263 DIN IEC 60263 IEC 61260 DIN EN 61260 IEC 61094

6、-4 DIN EN 61094-4 GUM DIN V ENV 13005 Amendments This standard differs from DIN EN 24869-3:1994-02 as follows: a) The title has been changed and the standard has been revised. b) The content of the former subclause 5.2 “Test signal” has been included in subclause 5.3 “Measuring system”. c) Subclause

7、 5.3 “Measuring system” no longer contains specific requirements concerning the measuring system. d) Annex B, dealing with uncertainty, has been added. Previous editions DIN V 45658: 1991-06 DIN EN 24869-3: 1994-02 DIN EN ISO 4869-3:2007-09 3 National Annex NA (informative) Bibliography DIN V ENV 13

8、005, Guide to the expression of uncertainty in measurement DIN EN 61094-4, Measurement microphones Part 4: Specifications for working standard microphones DIN EN 61260, Electroacoustics Octave-band and fractional-octave-band filters DIN IEC 60263, Scales and sizes for plotting frequency characterist

9、ics and polar diagrams DIN ISO 48, Rubber, vulcanized or thermoplastic Determination of hardness (hardness between 10 IRHD and 100 IRHD) DIN ISO 4869-1, Acoustics Hearing protectors Subjective method for the measurement of sound attenuation DIN EN ISO 4869-3:2007-09 4 This page is intentionally blan

10、k EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 4869-3 July 2007 ICS 13.340.20 Supersedes EN 24869-3:1993 English Version Acoustics - Hearing protectors - Part 3: Measurement of insertion loss of ear-muff type protectors using an acoustic test fixture (ISO 4869-3:2007) Acoustique - Protec

11、teurs individuels contre le bruit - Partie 3: Mesurage de laffaiblissement acoustique des protecteurs du type serre-tte au moyen dun montage dessai acoustique (ISO 4869-3:2007) Schalldmmung von Kapselgehrschtzern unter Verwendung einer akustischen Prfvorrichtung (ISO 4869-3:2007) This European Stand

12、ard was approved by CEN on 30 June 2007. CEN members 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 suc

13、h national standards may be obtained on application to the CEN Management Centre 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 languag

14、e and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxem

15、bourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All ri

16、ghts of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 4869-3:2007: EAkustik - Gehrschtzer - Teil 3: Messung der Foreword This document (EN ISO 4869-3:2007) has been prepared by Technical Committee ISO/TC 43 “Acoustics” in collaboration with Te

17、chnical Committee CEN/TC 211 “Acoustics”, the secretariat of which is held by DS. 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 January 2008, and conflicting national standards shall be withdraw

18、n at the latest by January 2008. This document supersedes EN 24869-3:1993. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). For relationship with EU Directive(s), s

19、ee informative Annex ZA, which is an integral part of this document. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia,

20、 Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 4869-3:2007 has been approved by CEN as EN

21、ISO 4869-3:2007 without any modifications. 2 EN ISO 4869-3:2007 (E) Introduction A Technical Report describing the use of an acoustic test fixture (ATF) to measure the insertion loss of ear-muff type protectors was published as ISO/TR 4869-3 in 1989. As testing laboratories around the world commonly

22、 use the ATF, it was decided that this Technical Report should be revised and changed into an International Standard. Compared to the original Technical Report, the most important aspect of this part of ISO 4869 is the specification of the ATF. The ATF specified herein is not intended to supplant th

23、ose dummy heads which include simulation of various anatomical features and which are used, for example, for development testing purposes. The method specified in this part of ISO 4869 does not provide results which are the same as those obtained by the subjective method, ISO 4869-1. 3 EN ISO 4869-3

24、:2007 (E) 1 Scope This part of ISO 4869 specifies a method for measuring the insertion loss of ear-muff type hearing protectors using an acoustic test fixture. The method is applicable to the investigation of production spreads of performance as part of type approval or certification procedures, and

25、 to the investigation of the change of performance with age. It is intended to ensure that ear-muff hearing protector samples submitted for subjective testing of attenuation according to ISO 4869-1 have performances typical of the type. The method specified in this part of ISO 4869 is not applicable

26、 as the basic test for type approval. Performance data obtained by this method are not intended to be quoted as representing the real-ear sound attenuation of an ear-muff, nor the protection provided by the ear-muff. For the testing of certain ear-muffs (such as those attached to safety helmets, or

27、those with contoured ear-cups or ear-cushions, or supra-aural ear-muffs), the procedure described in this part of ISO 4869 might need to be modified. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the editi

28、on cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 48, Rubber, vulcanized or thermoplastic Determination of hardness (hardness between 10 IRHD and 100 IRHD) ISO 4869-1, Acoustics Hearing protectors Part 1: Subjective method

29、 for the measurement of sound attenuation ISO/IEC Guide 98:1995, Guide to the expression of uncertainty in measurement (GUM) IEC 60263, Scales and sizes for plotting frequency characteristics and polar diagrams IEC 61260, Electroacoustics Octave-band and fractional-octave-band filters IEC 61094-4, M

30、easurement microphones Part 4: Specifications for working standard microphones 4 EN ISO 4869-3:2007 (E) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 hearing protector device worn by a person to reduce unwanted auditory effects from acousti

31、c stimuli 3.2 ear-muff hearing protector consisting of a supra-aural ear-cup to be pressed against each pinna or of a circumaural ear-cup to be pressed against the head around the pinna NOTE The ear-cups can be pressed against the head with a special headband or neck-band or by means of a device att

32、ached to a safety helmet or other equipment. 3.3 head-strap flexible strap fitted to each cup, or to the headband close to the cup NOTE The strap can be adjusted to support the ear-muffs, usually for behind-the-head types, by resting on the top of the head. 3.4 acoustic test fixture ATF device that

33、approximates certain dimensions of an average adult human head NOTE An ATF is used for measuring the insertion loss of hearing protectors of the ear-muff type and includes a microphone for measuring sound pressure levels. 3.5 insertion loss algebraic difference, in decibels, between the one-third-oc

34、tave-band sound pressure level measured by the microphone of the acoustic test fixture with the hearing protector absent and the sound pressure level with the hearing protector present 3.6 pink noise noise in which sound power spectral density is inversely proportional to frequency 3.7 acoustic isol

35、ation algebraic difference, in decibels, between the one-third-octave-band sound pressure level measured by the microphone of the acoustic test fixture with a specially designed sound isolation test cup absent and the sound pressure level with the specially designed sound isolation test cup present

36、3.8 noise floor output level of the measurement system with the test signal switched off and a test cup providing sufficient acoustic isolation in position 3.9 reference point midpoint of a line connecting the centres of the two end faces of the acoustic test fixture 5 EN ISO 4869-3:2007 (E) 4 Measu

37、rement principle The level of a test signal in a defined sound field is measured by a microphone located in an acoustic test fixture (ATF). The level is measured without and with the microphone being occluded by the ear-muff under test. The difference between the two measurement results is the inser

38、tion loss of the hearing protector. The ATF shall allow an ear-muff to be placed properly by positioning one ear-cup of the hearing protector over a measuring microphone. 5 Measurement of the insertion loss of ear-muffs 5.1 Acoustic test fixture (ATF) 5.1.1 General An example of an ATF is given in F

39、igure 1. 5.1.2 Description The ATF shall be made of a non-magnetic material, for example aluminium alloy or brass. It shall be in the shape of a cylinder with its axis horizontal and with (145 1) mm between the centres of the two end faces. The diameter of the cylinder shall be (135 5) mm. The angle

40、s of each of the two end faces shall be inclined towards the top at 4,5 0,5 to a vertical plane. The measuring microphone shall be of type WS1P or WS2P in accordance with IEC 61094-4. It shall be of the pressure-operated condenser type. The microphone shall be placed with its centre axis coinciding

41、with the centre axis of the cylinder. The centre of the microphone diaphragm shall be in the plane of one of the end faces of the cylinder on the centre line. See Figure 2. To reduce structure-borne sound, the ATF shall be supported in the test sound field with a resilient mounting so as to achieve

42、a sufficiently low noise floor. The vertical and horizontal diameters shall be marked at the end faces of the ATF, along with two or three concentric circles of suitable radius to help in positioning the ear-muff properly. The marking shall not produce any acoustical leakage. It may be necessary to

43、equalize the static pressure under the ear-muff during fitting. This may be achieved by: a) a capillary tube that is placed between the cushion and the ATF surface during the fitting of the ear-muff to the fixture, and which is removed before the measurements; care shall be taken not to permanently

44、deform the cushion; b) a fixed capillary tube connecting the cavity under the ear-muff to the external air; the tube shall be of diameter 0,5 mm, of length 25 mm, parallel with and near to the axis of the microphone of the acoustic test fixture, partly closed by a wire of diameter 0,4 mm and combine

45、d with a tube of diameter about 3 mm extending from the bottom of the cylinder perpendicular to the microphone axis. 5.1.3 Spacer A spacer shall project from the cylinder at right angles to the centre axis of the cylinder to support the headband of the ear-muff under test. The spacer shall be of len

46、gth (123 1) mm from the centre axis of the cylinder. The free end of the spacer shall have a cylindrical radius of (100 1) mm. A rubber pad (6 1) mm thick and of hardness within the range 30 IRHD to 85 IRHD (see ISO 48) shall be attached to the end of the spacer to provide slightly resilient seating

47、 for the ear-muff headband. The free face of the rubber pad shall be (50 1) mm wide and (77 1) mm long. 6 EN ISO 4869-3:2007 (E) 5.1.4 Acoustic isolation The acoustic isolation of the ATF shall be at least 50 dB for test bands with centre frequencies between 63 Hz and 250 Hz, at least 65 dB for cent

48、re frequencies between 315 Hz and 4 kHz, and at least 55 dB for higher test centre frequencies at the actual test site, measured with the test signal described in 5.3 and with the microphone covered by a suitable acoustic isolation test cup (e.g. the one shown in Figure 1). The isolation test cup sh

49、all be sealed to the ATF. The acoustic isolation test cup may be attached to the test fixture by turning the centre axis of the fixture in a vertical position or by fixing a rubber band around the ATF and the cup. If a fixed tube for pressure equalization is used, it should be closed at the bottom of the cylinder after the isolation test cup has been fixed. 5.2 Test site 5.2.1 General The test sound field shall consist of either a random incidence field or a plane progressive wave of a quality specified in 5.2.2 and