SIST EN 13819-1:2003
(Main)Hearing protectors - Testing - Part 1: Physical test methods
Hearing protectors - Testing - Part 1: Physical test methods
This European Standard prEN 13819 describes methods of tests for hearing protectors. The purpose of these tests is to enable assessment of the performance of the hearing protector as specified in the appropriate product standard. This Part 1 of the prEN 13819 specifies physical test methods.
Gehörschützer - Prüfung - Teil 1: Physikalische Prüfverfahren
Diese Europäische Norm EN 13819-1 legt physikalische Prüfverfahren für Gehörschützer fest. Zweck dieser Prüfungen ist, die Beurteilung der Leistungsfähigkeit des Gehörschützers, wie sie in der jeweiligen Produktnorm festgelegt ist, zu ermöglichen.
Protecteurs individuels contre le bruit - Essais - Partie 1: Méthodes d'essai physique
La présente Norme européenne EN 13819 décrit des méthodes d'essai pour les protecteurs contre le bruit. L'objectif de ces essais est de permettre l'évaluation des performances du protecteur contre le bruit comme spécifié dans la norme de produit appropriée.
Varovala sluha - Preskušanje - 1. del: Fizikalne preskusne metode
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 13819-1:2003
01-april-2003
Varovala sluha - Preskušanje - 1. del: Fizikalne preskusne metode
Hearing protectors - Testing - Part 1: Physical test methods
Gehörschützer - Prüfung - Teil 1: Physikalische Prüfverfahren
Protecteurs individuels contre le bruit - Essais - Partie 1: Méthodes d'essai physique
Ta slovenski standard je istoveten z: EN 13819-1:2002
ICS:
13.340.20 Varovalna oprema za glavo Head protective equipment
SIST EN 13819-1:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN 13819-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2002
ICS 13.340.20
English version
Hearing protectors - Testing - Part 1: Physical test methods
Protecteurs individuels contre le bruit - Essais - Partie 1: Gehörschützer - Prüfung - Teil 1: Physikalische
Méthodes d'essai physique Prüfverfahren
This European Standard was approved by CEN on 9 September 2002.
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 such national
standards may be obtained on application to the 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 language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2002 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13819-1:2002 E
worldwide for CEN national Members.
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EN 13819-1:2002 (E)
Contents
page
Foreword.3
Introduction .4
1 Scope .5
2 Normative references.5
3 Terms and definitions .5
4 Ear-muffs.6
4.1 Specimens, conditioning and scheme of testing.6
4.2 Adjustability .8
4.3 Cup rotation.12
4.4 Headband force.14
4.5 Cushion pressure .15
4.6 Resistance to damage when dropped.17
4.7 Resistance to damage when dropped at low temperature (optional) .18
4.8 Headband flexing .20
4.9 Stand-by mechanism durability test (helmet mounted ear-muffs only).20
4.10 Water immersion .21
4.11 Water Immersion - headband under stress (optional).21
4.12 Resistance to leakage (fluid filled cushions only).22
4.13 Ignitability.22
5 Ear-plugs .23
5.1 Specimens, conditioning and scheme of testing.23
5.2 Assessment of nominal diameter designation .24
5.3 Range of fitting of headband ear-plugs.25
5.4 Resistance to damage when dropped.26
5.5 Resistance to damage when dropped at low temperature (optional) .27
5.6 Ignitability .27
Annex A (informative) Uncertainty of measurement and interpretation of test results.40
Annex ZA (informative) Clauses of this European standard addressing essential requirements
or other provisions of EU Directives.42
Bibliography .43
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EN 13819-1:2002 (E)
Foreword
This document (EN 13819-1:2002) has been prepared by Technical Committee CEN/TC 159, "Hearing protectors",
the secretariat of which is held by SIS.
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 June 2003, and conflicting national standards shall be withdrawn at the latest by
June 2003.
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), see informative annex ZA, which is an integral part of this standard.
In this European Standard the annex A is informative.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain,
Sweden, Switzerland and the United Kingdom.
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EN 13819-1:2002 (E)
Introduction
This standard for ”Hearing Protectors - Testing : Part 1 - Physical test methods”, specifies procedures for the
testing of personal hearing protection devices in relation to Directive 89/686/EEC - Personal Protective Equipment.
EN 352-1 deals with requirements for ear-muffs, EN 352-2 with ear-plugs, EN 352-3 with ear-muffs attached to
industrial safety helmets. EN 13819 deals with testing plans common to all types of hearing protectors and
consists of two Parts:
Part 1: Physical test methods
Part 2: Acoustic test methods.
Additional safety requirements and the associated test procedures for level-dependent ear-muffs are contained in
EN 352-4, for ear-muffs with active noise reduction in EN 352-5, for ear-muffs with audio communications in
EN 352-6 and for level-dependent ear-plugs in EN 352-7.
An associated standard EN 458, covers selection, use, care and maintenance of hearing protectors.
This standard is intended as a supplement to the specific product standards for hearing protectors.
The performance requirements are given in the hearing protector product standard.
If deviations from the procedures specified in this standard are necessary, these deviations are specified in the
hearing protection standard.
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EN 13819-1:2002 (E)
1 Scope
This European Standard EN 13819-1 specifies physical test methods for hearing protectors. The purpose of these
tests is to enable assessment of the performance of the hearing protector as specified in the appropriate product
standard.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this European
Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
EN 352-1:2002, Hearing protectors - General requirements - Part 1: Ear-muffs
EN 352-2: 2002, Hearing protectors - General requirements - Part 2: Ear-plugs
EN 352-3:2002, Hearing protectors - General requirements - Part 3: Ear-muffs attached to an industrial safety
helmet
EN 960:1994, Headforms for use in the testing of protective helmets
EN 13819-2:2002, Hearing protectors - Testing - Part 2: Acoustic test methods
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply, in addition to those given in
EN 352 parts 1,2 and 3.
3.1
headband ear-muffs
ear-muffs satisfying the requirements of EN 352-1.
3.2
helmet mounted ear-muffs
ear-muffs fitted to a helmet such that the combination satisfies the requirements of EN 352-3.
3.3
1)
test height
vertical distance between the axis through the centres of the mounting holes of the pinna simulators in the
mounting fixture or test headform shown in Figures 3 or 4 respectively, and the top of the headband support pad or
headform.
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EN 13819-1:2002 (E)
3.4
1)
test width
horizontal distance between the vertical axes through the centres of the mounting holes for the pinna simulators in
the mounting fixture or test headform shown in Figure 3 or 4 respectively.
3.5
1)
test depth
vertical distance between the axis through the centres of the mounting holes of the pinna simulators and the top of
the headband support, with the pinna simulators attached with their shorter axes vertical shown in Figure 3.
3.6
wearing height
vertical distance from the lower edge of the headband of the helmet to the highest point of the test headform on
which the helmet is mounted.
NOTE The headband of the helmet is defined in EN 397 as "The part of the harness completely or partly surrounding
the head above the eyes at approximately the largest horizontal circumference of the head".
4 Ear-muffs
4.1 Specimens, conditioning and scheme of testing
4.1.1 Specimens
Headband ear-muffs and helmet mounted ear-muffs shall be submitted for testing in the condition in which they are
offered for sale.
For headband ear-muffs, 10 specimens shall be submitted and they shall be numbered 1 to 10.
For helmet mounted ear-muffs, 10 basic combination specimens (ear-muffs and helmets) shall be submitted and
they shall be numbered 1 to 10 (basic).
If the same model of helmet mounted ear-muffs is to be tested with another model or size of helmet, 6 further
supplementary combination specimens (ear-muffs and helmets) for each model or size of helmet shall be
submitted. These shall be numbered (in sets) 1 to 6 (supplementary).
4.1.2 Conditioning and testing atmosphere
All specimens shall be conditioned and tested in an atmosphere having a temperature of (22 ± 5) °C and a relative
humidity of not more than 85 %, unless required otherwise by the test procedure.
4.1.3 Scheme of testing
4.1.3.1 The 10 headband ear-muffs shall be conditioned and tested in accordance with 4.1.3.2 to 4.1.3.9 and
Figure 1.
For helmet mounted ear-muffs, except as specified in the following paragraph, the scheme of testing for the 10
basic combination specimens and, if applicable, the sets of 6 supplementary combination specimens, shall be as
given in 4.1.3.2 to 4.1.3.9 and Figure 2.
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EN 13819-1:2002 (E)
In the case of helmets supplied in more than one size, one selected size shall be used for testing in a basic
combination (except for sound attenuation testing). All other helmet sizes shall be tested in a supplementary
combination (except for sound attenuation testing). Sound attenuation testing shall be performed using the
complete range of available helmet sizes (see EN 13819-2). If the helmet mounted ear-muff incorporates a means
to adjust the headband force, the force shall be adjusted to its minimum setting for all stages of conditioning and
testing, unless otherwise specified.
NOTE Testing may be discontinued in the event of a specimen failing to satisfy the respective requirement.
4.1.3.2 Unpack all ear-muffs completely.
4.1.3.3 For helmet mounted ear-muffs, each specimen shall be weighed and the mean mass of the 10 specimens
shall be reported to the nearest gram.
4.1.3.4 In the case of helmet mounted ear-muffs, the ear-muffs shall be attached to the helmets in accordance with
the ear-muffs manufacturer’s instructions. The cups/support arms shall be set to the mid-point of the range of their
adjustment and set in the position (in-use, stand-by, parking etc) as received from the manufacturer.
4.1.3.5 All specimens shall be conditioned for not less than 4 h in the atmosphere specified in 4.1.2.
4.1.3.6 For headband ear-muffs, each specimen shall be weighed and the mean mass of the 10 specimens shall
be reported to the nearest gram.
4.1.3.7 The scheme of testing for specimens 1 to 6 (headband ear-muffs and helmet mounted ear-muffs, basic and
supplementary sets) shall be as follows:
a) Test each specimen in accordance with 4.2, 4.3, 4.4 and 4.5;
b) Test each specimen in accordance with 4.6, unless (optional) 4.7 is to be performed;
c) Optionally, test each specimen in accordance with 4.7;
d) Test each specimen in accordance with 4.8 or, if the specimen is helmet mounted ear-muffs which incorporate
a stand-by position, test in accordance with 4.9 (includes support arm flexing);
e) Remove the cups (if possible) or the cushions and liners from each of the cups of each specimen, identifying
the cups or liners to enable subsequent identical re-assembly. If the cups are not removable and cushions or
liners are not removable and/or replaceable, the cushions and liners shall be protected from the water
immersion during the testing;
f) Test each specimen in accordance with 4.10, unless (optional) 4.11 is to be performed;
g) Optionally, test each specimen in accordance with 4.11;
h) Remove each specimen from the water bath noting the time of removal and re-fit the cups (if removed).
Remove excess water. If the liners were removed, re-fit them, and for all specimens with replaceable cushions
fit new cushions to each of the cups in accordance with the manufacturer's instructions;
i) Condition each specimen for 24 h ± 10 min, measured from the time of removal from the water bath in h),
under the conditions specified in 4.1.2, and then immediately measure the headband force in accordance with
4.4;
NOTE For multiple size range models, use the setting of width and height which gave the highest headband force in 4.4;
j) For helmet mounted ear-muffs set the cups/support arms to the mid-point of the range of their adjustment, set
in the position (in-use, stand-by, parking etc.) as received from the manufacturer.
4.1.3.8 The scheme of testing for all 10 headband ear-muffs specimens or, in the case of helmet mounted ear-
muffs, all 10 basic specimens, shall be continued as follows:
a) Measure the insertion loss of each cup of each specimen in accordance with EN 13819-2:2002, 4.1;
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EN 13819-1:2002 (E)
b) Calculate the standard deviation of insertion loss for all 20 cups, using (N-1) weighting for the sample data.
4.1.3.9 The scheme of testing for specimens 5 and 6, or, in the case of helmet mounted ear-muffs, both basic and
supplementary specimens 5 and 6, shall be continued as follows:
a) If appropriate, test both specimens or, in the case of helmet mounted ear-muffs, both basic (only) specimens,
in accordance with 4.12;
b) Assess both specimens, or, in the case of helmet mounted ear-muffs, both basic and supplementary
specimens, for compliance with EN 352-1:2002, 4.2 or EN 352-3:2002, 4.2, as appropriate;
c) Test both specimens, or, in the case of helmet mounted ear-muffs, both the basic and, if required by EN 352-
3:2002, 4.3.4, the supplementary specimens, in accordance with 4.13.
4.1.3.10 The scheme of testing for specimens 1 to 4, or, in the case of helmet mounted ear-muffs, both basic and
supplementary specimens 1 to 4, shall be continued as follows:
Measure the sound attenuation of the specimens in accordance with EN 13819-2:2002, 4.2.
4.2 Adjustability
4.2.1 Principle
The ability of the ear-muffs to be adjusted to fit specified test dimensions is assessed using a suitable mounting
fixture (headband ear-muffs) or test headforms (helmet mounted ear-muffs).
4.2.2 Apparatus
4.2.2.1 Mounting fixture
The outline of an example is shown in Figure 3.
4.2.2.2 Test headforms
These shall be in accordance with the dimensions given in EN 960:1994, for sizes B, J and N. Details are given in
Figure 4.
4.2.2.3 Pinna simulators
The required dimensions are shown in Figure 5.
4.2.2.4 Non-planar cushion adaptor
For ear-muffs with non-planar cushions, the manufacturer shall supply suitable adaptors which shall be fitted to the
mounting fixture, such that, when the ear-muffs are then fitted to the mounting fixture, and with the plates of the
latter set parallel, the centres of the openings of the ear-muffs cushions lie on the horizontal axis through the centre
of the force transducer.
4.2.3 Procedure
4.2.3.1 Headband ear-muffs
4.2.3.1.1 Fit the pinna simulators to the plates of the apparatus so that their longer axes are vertical for
over-the-head and under-the-chin ear-muffs or so that their shorter axes are vertical for behind-the-head ear-muffs.
4.2.3.1.2 Adjust the cups/headband to their longest position and, if the ear-muffs incorporate a means to adjust the
headband force, adjust the force to its maximum setting.
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EN 13819-1:2002 (E)
4.2.3.1.3 Place the ear-muffs on the fixture so that the headband is vertical and the pinna simulators are enclosed
by the cushions.
4.2.3.1.4 Adjust the separation of the plates and the height of the headband support to correspond in turn and as
appropriate with each of the combinations of dimensions of width and height respectively shown in Table 1 or
Table 2, as appropriate.
4.2.3.1.5 For each of the combinations of dimensions of width and height respectively, check whether the range of
adjustment of the cups/headband and of the width between the cushions enable the ear-muffs to be fitted so that:
a) for over-the-head ear-muffs, the internal apex of the headband touches the headband support pad, or, for
behind-the-head or under-the-chin ear-muffs, the internal apex of the headband touches or lies beyond the
headband support pad;
NOTE For those ear-muffs, which, because of their design, cannot be assessed correctly by this method (for
example, those behind-the-head ear-muffs where the headband is designed to pass only around the back of the neck), this
test isbe performed using the appropriate test headforms as specified in EN 960:1994, sizes B, J and N (full headforms,
including chin and neck), fitted with pinna simulators at the heights given in figure 4 appropriate to the ear-muff size range.
b) the contact between the cushions and the plates of the fixture is continuous insofar as it provides an unbroken
barrier between the inside and outside perimeters of the cushions.
NOTE Discontinuity in contact between the cushions and the plates is acceptable in the region where the pinna
simulator mounting area (46 mm x 10 mm) lies on the plates.
4.2.3.1.6 If the ear-muffs incorporate a means to adjust the headband force, adjust the force to its minimum setting
and repeat steps 4.2.3.1.4 and 4.2.3.1.5.
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EN 13819-1:2002 (E)
Table 1 — Test dimensions – adjustability
(over-the-head and under-the-chin ear-muffs)
Test height Test width
mm mm
125 145 155
115
SS/M --
130
S/M S/M/L M/L
140
-- M/L L
M indicates ear-muffs of ‘medium’ size range;
S indicates ear-muffs of 'small' size range;
L indicates ear-muffs of 'large' size range;
-- indicates no requirement.
Table 2 — Test dimensions - adjustability
(behind-the-head ear-muffs)
Test depth Test width
mm mm
125 145 155
75 SS/M --
90 S/M S/M/L M/L
105 -- M/L L
M indicates ear-muffs of ‘medium’ size range;
S indicates ear-muffs of 'small' size range;
L indicates ear-muffs of 'large' size range;
-- indicates no requirement.
NOTE 1 The dimensions given in Tables 1 and 2 have been chosen to cover appropriate combinations of the head
width, head height and head depth of the 5th, 50th and 95th percentiles of the adult population.
NOTE 2 If non-planar cushion adaptors are fitted to the mounting fixture, test width is the dimension between the two
outermost points of the cushion adaptors measured along the horizontal axis through the centre of the force transducer.
4.2.3.2 Helmet mounted ear-muffs
4.2.3.2.1 Fit the pinna simulators to the side plates of the test headforms so that their longer axes are vertical and
coincident with the transverse vertical axis of the headform. Adjust their vertical position as necessary to
correspond with the test heights given in Table 3.
4.2.3.2.2 Adjust the harness of the helmet to give the minimum wearing height and the maximum external vertical
distance, in accordance with the helmet manufacturer’s instructions.
NOTE This adjustment assumes continuing compliance of these dimensions with the requirements of EN 397.
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EN 13819-1:2002 (E)
4.2.3.2.3 If the helmet mounted ear-muffs incorporates a means to adjust the headband force, adjust the force to its
maximum setting.
4.2.3.2.4 Place the helmet mounted ear-muff on each headform in turn, in the as-worn position, and so that the
pinna simulators are enclosed by the cushions. Maintain the helmet in position by the application of a force of
nominally 50 N acting along the vertical axis.
4.2.3.2.5 For each of the combinations of dimensions of width and height respectively shown in Table 3, check
whether the adjustment of the cups/support arms and of the width between the cushions enable the helmet
mounted ear-muff to be fitted to the fixture so that:
a) the contact between the cushions and the plates of the headform is continuous insofar as it provides an
unbroken barrier between the inside and outside perimeters of the cushions;
NOTE Discontinuity in contact between the cushions and the plates is acceptable in the region where the
pinna simulator mounting area (46 mm x 10 mm) lies on the plates and in any region where the headband of
the helmet harness lies under the cushions.
b) the stand-by position of the ear-muffs is not induced.
4.2.3.2.6 If the helmet mounted ear-muffs incorporate a means to adjust the headband force, adjust the force to its
minimum setting and repeat steps 4.2.3.2.4 and 4.2.3.2.5.
Table 3 — Test dimensions – adjustability (helmet mounted ear-muffs)
Test width
Test height
mm
mm
125
145 155
115 SS/M --
130 S/M S/M/L M/L
140 -- M/L L
Corresponding BJ N
EN 960 test headform
M indicates ear-muffs of ‘medium’ size range.
S indicates ear-muffs of 'small' size range.
L indicates ear-muffs of 'large' size range.
-- indicates no requirement.
NOTE 1 The dimensions given in Table 3 have been chosen to cover appropriate combinations of the head width and
head height of the 5th, 50th and 95th percentiles of the adult population.
NOTE 2 If non-planar cushion adaptors are fitted to the mounting fixture, test width is the dimension between the two
outermost points of the cushion adaptors measured along the horizontal axis through the centre of the force transducer.
4.2.4 Report
Report the observations noted in accordance with 4.2.3.1.5 or 4.2.3.2.5.
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EN 13819-1:2002 (E)
4.3 Cup rotation
4.3.1 Principle
The ear-muffs are set to be at a given adjustment and the ability of the cups to accommodate a range of angular
movement is tested using a suitable mounting fixture.
4.3.2 Apparatus
4.3.2.1 Mounting fixture
The outline of examples are shown in Figures 3 and 6.
4.3.2.2 Pinna simulators
The required dimensions are shown in Figure 5.
4.3.2.3 Non-planar cushion adaptor
For ear-muffs with non-planar cushions, the manufacturer shall supply suitable adaptors which shall be fitted to the
mounting fixture, such that, when the ear-muffs are then fitted to the mounting fixture, and with the plates of the
latter set parallel, the centres of the openings of the ear-muffs cushions lie on the horizontal axis through the centre
of the force transducer.
4.3.3 Procedure
4.3.3.1 Headband ear-muffs
4.3.3.1.1 Fit the pinna simulators to the plates of the mounting fixture so that their longer axes are vertical for
over-the-head and under-the-chin ear-muffs or so that their shorter axes are vertical for behind-the-head ear-muffs.
4.3.3.1.2 Adjust the two plates so that they are angled at 5 degrees to the vertical with their top edges out and their
separation, measured on the horizontal centre line, corresponds to the appropriate test width given in Table 4.
4.3.3.1.3 If the ear-muffs incorporate a means to adjust the headband force, adjust the force to its maximum
setting.
4.3.3.1.4 Place the ear-muffs on the mounting fixture so that the headband is vertical and the pinna simulators are
enclosed by the cushions. Adjust the cups/headband to correspond to the appropriate test height given in Table 4.
4.3.3.1.5 Rotate the plates ± 5° about a horizontal axis through the centre and in the plane of the plates and ± 5°
about a second axis still in the plane of the plates but orthogonal to the horizontal axis used, so as to maintain
symmetry of the arrangement about the vertical axis of the mounting fixture.
4.3.3.1.6 Observe whether the contact between the cushions and the plates is continuous throughout this range.
NOTE Discontinuity in contact between the cushions and the plates is acceptable in the region where the pinna
simulator mounting area (46 mm x 10 mm) lies on the plates.
4.3.3.1.7 If the ear-muffs incorporate a means to adjust the headband force, adjust the force to its minimum setting
and repeat steps 4.3.3.1.4 to 4.3.3.1.6.
4.3.3.1.8 In the case of multiple size range models, repeat steps 4.3.3.1.2 to 4.3.3.1.7 at the other appropriate test
widths and heights.
4.3.3.2 Helmet mounted ear-muffs
4.3.3.2.1 Fit the pinna simulators centrally on the plates of the mounting fixture so that their longer axes are
vertical.
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EN 13819-1:2002 (E)
4.3.3.2.2 Adjust the two plates so that they are angled at 5 degrees to the vertical with their top edges out and their
separation, measured on the horizontal centre line, corresponds to the appropriate test width given in Table 4.
4.3.3.2.3 Remove the harness from the helmet and drill as small a diameter hole as possible through the shell on
the central vertical axis, so as to enable the mounting bolt to pass through and to secure the shell to the helmet
support pad of the mounting fixture.
4.3.3.2.4 Place the helmet mounted ear-muffs on the mounting fixture and secure with the mounting bolt.
4.3.3.2.5 If the helmet mounted ear-muffs incorporate a means to adjust the headband force, adjust the force to its
maximum setting.
4.3.3.2.6 Adjust the cups/support arms to correspond to the appropriate test height given in Table 4 and adjust the
height of the mounting fixture helmet support pad (to which the helmet shell is bolted) so that the pinna simulators
are enclosed by the cushion
...
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