EN 458:2016

SLOVENSKI STANDARD
01-junij-2016
1DGRPHãþD
SIST EN 458:2005
9DURYDODVOXKD3ULSRURþLOD]DL]ELURXSRUDERQHJRLQY]GUåHYDQMH1DYRGLOR
Hearing protectors - Recommendations for selection, use, care and maintenance -
Guidance document
Gehörschützer - Empfehlungen für Auswahl, Einsatz, Pflege und Instandhaltung -
Leitfaden
Protecteurs individuels contre le bruit - Recommandations relatives à la sélection, à
l'utilisation, aux précautions d'emploi et à l'entretien - Document guide
Ta slovenski standard je istoveten z: EN 458:2016
ICS:
13.340.20 Varovalna oprema za glavo Head protective equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 458
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2016
EUROPÄISCHE NORM
ICS 13.340.20 Supersedes EN 458:2004
English Version
Hearing protectors - Recommendations for selection, use,
care and maintenance - Guidance document
Protecteurs individuels contre le bruit - Gehörschützer - Empfehlungen für Auswahl, Einsatz,
Recommandations relatives à la sélection, à Pflege und Instandhaltung - Leitfaden
l'utilisation, aux précautions d'emploi et à l'entretien -
Document guide
This European Standard was approved by CEN on 8 August 2015.

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 CEN-CENELEC 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 CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 458:2016 E
worldwide for CEN national Members.

Contents Page
European foreword . 5
Introduction . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Symbols and abbreviations . 9
5 Types of hearing protectors . 9
5.1 Design forms . 9
5.1.1 Earmuffs . 9
5.1.2 Helmet mounted earmuffs . 10
5.1.3 Earplugs . 10
5.2 Function mode . 10
5.2.1 Basic function mode . 10
5.2.2 Level-dependent hearing protectors . 11
5.2.3 Active noise reduction (ANR) protectors . 11
5.2.4 Hearing protectors with external audio input . 11
6 Selection . 12
6.1 Principles . 12
6.2 Selection according to sound attenuation . 12
6.2.1 Guide to protection rating . 12
6.2.2 Sound attenuation in practice (Real-world attenuation) . 13
6.2.3 Acoustical selection methods . 13
6.2.4 Selection of combination of earmuffs and earplugs . 15
6.3 Selection according to work environment . 15
6.3.1 Factors of work environment – overview . 15
6.3.2 Acoustical factors . 15
6.3.3 Environmental factors (non-acoustic) . 17
6.4 Communication . 19
6.4.1 Essential work related speech communication, especially speech intelligibility . 19
6.4.2 Effects of over-protection . 19
6.5 Compatibility with other PPE . 19
6.6 Selection according to hearing protector types . 19
6.6.1 Earmuffs – General. 19
6.6.2 Helmet-mounted earmuffs . 19
6.6.3 Earplugs – General . 19
6.6.4 Hearing protectors with additional function modes . 20
6.7 Medical disorders. 20
6.8 Ergonomics and fitting . 20
6.9 Conformity with relevant requirements for incorporated electronics . 21
6.9.1 Intrinsic safety . 21
6.9.2 Electromagnetic compatibility (EMC) . 21
7 Use . 21
7.1 General . 21
7.2 Availability of hearing protectors . 21
7.3 Correct fitting . 21
7.3.1 General . 21
7.3.2 Earmuffs . 21
7.3.3 Earplugs . 22
7.3.4 Fit check for hearing protectors . 22
7.4 Simultaneous use of hearing protector with other PPE . 22
7.4.1 General . 22
7.4.2 Protective clothing . 22
7.4.3 Spectacles . 22
7.4.4 Goggles . 22
7.4.5 Face shields . 22
7.4.6 Hoods . 23
7.4.7 Safety helmets . 23
7.4.8 Respiratory protection devices . 23
7.5 Speech intelligibility and signal audibility . 23
7.6 Instruction and training . 23
7.6.1 General . 23
7.6.2 Information . 23
7.6.3 Special instructions for use including training . 24
7.7 Period of use . 24
7.8 Leisure activities . 25
8 Care and maintenance . 25
8.1 General . 25
8.2 Hygiene and cleaning . 25
8.3 Inspection and replacement . 25
8.4 Storage . 25
8.5 Disposal . 25
Annex A (normative) Methods for assessing the sound attenuation of a passive hearing
protector . 26
A.1 General . 26
A.2 Octave band method . 29
A.3 HML method . 30
A.4 HML check method . 32
A.5 SNR method . 33
Annex B (informative) Method for assessing the sound attenuation of a hearing protector
for impulsive noise . 34
B.1 General . 34
B.2 Method . 34
Annex C (informative) Selection method for sound-restoration level-dependent hearing
protectors using HML-data . 36
C.1 General . 36
C.2 Method 1: HML Method . 36
C.3 Method 2A: HML check method - Measurement check . 37
C.4 Method 2B: HML check method - Listening method. 37
Annex D (informative) Selection method for active noise reduction hearing protectors . 38
Annex E (informative) Calculation method for hearing protectors with audio input . 39
E.1 General . 39
E.2 Method . 39
Annex F (informative) Improving field performance and special instructions for use . 41
F.1 Improving field performance . 41
F.2 Special instructions for optimum use . 42
Annex G (informative) Further guidance on fit check methods for earplugs . 45
G.1 General information . 45
G.2 Fit check methods suitable for all types of earplugs . 45
G.3 Fit check method exclusive to custom moulded earplugs . 46
Annex H (informative) Noise Types . 47

European foreword
This document (EN 458:2016) has been prepared by Technical Committee CEN/TC 159 “Hearing
protectors”, the secretariat of which is held by DIN.
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 September 2016, and conflicting national standards
shall be withdrawn at the latest by September 2016.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document supersedes EN 458:2004.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
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,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Introduction
This European Standard is intended to guide employers, supervisors and safety advisors. Additionally,
the standard gives information to all who need to use hearing protectors.
Hearing protectors are items of personal protective equipment (PPE) intended to reduce the harmful
effects that sound and noise may have on the hearing.
Guidance is provided on how to best select, use and take care of such devices. Tools to estimate the
noise exposure level, when a certain hearing protector is used, are also provided.
National bodies may develop national application documents based on this standard.
Hearing protectors are generally available in two main forms: earmuffs and earplugs. Both forms are
available with additional features and functions. All have their advantages and disadvantages in terms
of attenuation, comfort, ease of use, communication facilities and cost.
In hearing conservation programmes noise hazard areas are identified and the personal noise exposure
is assessed. Before a suitable hearing protector is considered, priority should be given to reducing noise
at source and/or reducing the exposure time.
If the use of a hearing protector is found necessary or advisable, choosing optimum devices is a complex
task. The most important concern is for the protector to provide sufficient attenuation.
It is often desirable to retain the ability to hear speech and warning signals. To achieve this, the hearing
protector should not overprotect. In particular, this needs attention at moderate noise levels.
Hearing protectors are supplied with attenuation data in various formats. The attenuation is expressed
in decibels and has been derived from laboratory tests. It is important to note that these data have been
achieved under controlled laboratory conditions using trained test subjects. Under real working
conditions, the attenuation achieved by the user may be lower than that generated by the laboratory
testing.
The performance of hearing protectors is subject to natural variability amongst users. Correct fitting,
training, regular inspection and user motivation are important to obtain the desired protection. Due to
the natural variability, it is not possible to calculate the exact attenuation that a certain hearing
protector will give for an individual. If a more accurate prediction is required, some form of individual
attenuation check can be made. At high noise level exposures it is advisable to seek expert advice. In
some cases dual protection i.e. the use of an earmuff and an earplug combination, may be required.
For hearing protectors to be effective they should be used at all times when the user is in a potentially
hazardous noise environment. When selecting hearing protectors, attention should be given to factors
influencing comfort and user preference.
1 Scope
This European Standard gives recommendations for the selection, use, care and maintenance of hearing
protectors.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 352-1, Hearing protectors — General requirements — Part 1: Ear-Muffs
EN 352-2, Hearing protectors — General requirements — Part 2: Ear-plugs
EN 352-3, Hearing protectors — General requirements — Part 3: Ear-muffs attached to an industrial
safety helmet
EN 352-4, Hearing protectors — Safety requirements and testing — Part 4: Level-dependent ear-muffs
EN 352-5, Hearing protectors — Safety requirements and testing — Part 5: Active noise reduction ear-
muffs
EN 352-6, Hearing protectors — Safety requirements and testing — Part 6: Ear-muffs with electrical
audio input
EN 352-7, Hearing protectors — Safety requirements and testing — Part 7: Level-dependent ear-plugs
EN 352-8, Hearing protectors — Safety requirements and testing — Part 8: Entertainment audio ear-
muffs
EN 24869-1, Acoustics — Hearing protectors — Subjective method for the measurement of sound
attenuation (ISO 4869-1)
EN 61672-1, Electroacoustics — Sound level meters — Part 1: Specifications (IEC 61672-1)
EN ISO 4869-2, Acoustics — Hearing protectors — Part 2: Estimation of effective A-weighted sound
pressure levels when hearing protectors are worn (ISO 4869-2)
EN ISO 7731, Ergonomics — Danger signals for public and work areas — Auditory danger signals
(ISO 7731)
EN ISO 9612, Acoustics — Determination of occupational noise exposure — Engineering method
(ISO 9612)
EN ISO 9921, Ergonomics — Assessment of speech communication (ISO 9921)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
daily noise exposure level (L )
EX,8h
A-weighted noise exposure level normalized to a nominal 8 h working day
3.2
peak sound pressure level (L )
p,Cpeak
C-weighted instantaneous peak sound pressure level according to EN ISO 9612
3.3
national regulation level (L' )
NR
daily noise exposure level (L ) effective to the ear according to national regulations
EX,8h
Note 1 to entry: National laws or regulations will stipulate at which levels of exposure hearing protectors shall
be provided or used.
3.4
national peak regulation level (L' )
NR,peak
peak pressure level L effective to the ear according to national regulations
p,Cpeak
Note 1 to entry: National laws or regulations will stipulate at which levels of exposure hearing protectors shall
be provided or used.
3.5
effective attenuation
measure of protection afforded by the hearing protector for the user
3.6
over-protection
selection and use of a hearing protector with too high attenuation which may lead to a sense of isolation
and difficulties with perception of sounds
3.7
A-weighted sound pressure level (L )
p,A
sound pressure level with frequency weighting A according to EN 61672-1
3.8
A-weighted sound pressure level effective to the ear (L' )
p,A
A-weighted diffuse field equivalent sound pressure level under the hearing protector for the external
sound pressure level L
p,A
3.9
C-weighted sound pressure level (L )
p,C
sound pressure level with frequency weighting C according to EN 61672-1
3.10
A-weighted equivalent sound pressure level effective to the ear (L' )
p,A,eqT
A-weighted diffuse field equivalent sound pressure level under the hearing protector for the external
sound pressure level for time period T L
p,A,eqT
Note 1 to entry: For simplicity of notation, the subscript T is omitted throughout the following text.
3.11
effective daily noise exposure level (L' )
EX,8h
A-weighted diffuse field equivalent sound pressure level under the hearing protector for the external
noise exposure level L
EX,8h
3.12
peak sound pressure level effective to the ear (L' )
p,Cpeak
C-weighted peak sound pressure level under the hearing protector for the external sound pressure level
L
p,Cpeak
3.13
flat frequency response
attenuation which is constant (or nearly constant) over the frequencies (H – L ≤ 9 dB)
Note 1 to entry: See A.1 for explanation of “H” and “L”.
4 Symbols and abbreviations
For the purposes of this document, the following symbols and abbreviations apply.
f centre frequency of the octave band in Hz
L equivalent sound pressure level
p,eq
L sound pressure level for a single octave band
p,oct
L , equivalent sound pressure level for a single octave band
p,oct eq
PNR predicted noise level reduction according to EN ISO 4869-2
APV assumed protection value APV according to EN ISO 4869-2
f f84
rms root mean square
L daily noise exposure level
EX,8h
L C-weighted peak sound pressure level
p,Cpeak
L' national regulation level
NR
L' national peak regulation level
NR,peak
L A-weighted sound pressure level
p,A
L' A-weighted sound pressure level effective to the ear
p,A
L C-weighted sound pressure level
p,C
L A-weighted equivalent sound pressure level
p,A,eqT
L C-weighted equivalent sound pressure level
p,C,eqT
L' A-weighted equivalent sound pressure level effective to the ear
p,A,eqT
L' effective daily noise exposure level
EX,8h
L' peak sound pressure level effective to the ear
p,Cpeak
NOTE For simplification of notation, the subscript T is omitted throughout the following text.
5 Types of hearing protectors
5.1 Design forms
5.1.1 Earmuffs
Earmuffs consist of cups which fit over the ears and are sealed to the head with soft cushions, usually
filled with foam and/or liquid. The cups are usually lined with sound absorptive material. They are
connected by a tensioning band (head band), usually made of metal and/or plastic. When the earmuff is
used behind-the-head or under-the-chin, a flexible head strap is sometimes fitted to each cup or to the
head band close to the cups to support the earmuff. Some earmuffs have one cup intended only for the
left ear and the other only for the right ear. Earmuffs may be available in ‘medium size range’, ‘small size
range’ and ‘large size range’ types. ‘Medium size range' earmuffs will fit the majority of users. ‘Small size
range' or ‘large size range' earmuffs are designed to fit users for whom ‘medium size range' earmuffs
are not suitable.
Earmuffs are available with head bands, neck bands, chin bands and universal bands. Earmuffs with
neck bands and chin bands permit the simultaneous using of a safety helmet. Universal bands can be
used over-the-head, behind-the-head or under-the-chin. Universal bands, neck bands and chin bands
may be complemented by head straps to ensure a reliable fit of the earmuff.
Requirements for earmuffs are specified in EN 352-1.
5.1.2 Helmet mounted earmuffs
Helmet mounted earmuffs consist of individual cups attached to arms that are mounted to an industrial
safety helmet or other equipment serving as carrier for the hearing protector. The arms are adjustable
so that the cups can be positioned over the ears.
Requirements for earmuffs attached to a helmet are specified in EN 352-3.
5.1.3 Earplugs
5.1.3.1 General
Earplugs are hearing protectors that are designed to be inserted into the ear canal or to cover the ear
canal entrance. They are sometimes provided with an interconnecting cord, head band or finger grips.
Earplugs can be either disposable (intended for single use) or reusable (intended for repeated use).
Requirements for earplugs are specified in EN 352-2.
5.1.3.2 Pre-shaped earplugs
Pre-shaped earplugs can readily be inserted into the ear canal without prior shaping. Pre-shaped
earplugs are available in a variety of materials. They may be available in a range of sizes.
5.1.3.3 User-formable earplugs
User-formable earplugs are made from compressible materials that the user forms before inserting
them into the ear canal. After insertion, these earplugs are designed to expand and form a seal within
the ear canal.
5.1.3.4 Banded earplugs
These are pre-shaped earplugs attached to a band which presses them into the ear canal or against the
entrance of the ear canal. Some are intended to be used in more than one position, e.g. with the band
under-the-chin.
5.1.3.5 Custom moulded earplugs
Custom moulded earplugs are individually moulded to fit the shape of the user’s ear canals. They can be
provided with different filters to offer a range of attenuation.
5.2 Function mode
5.2.1 Basic function mode
All hearing protectors have the characteristics of reducing noise by their design and type of material
used, to absorb and/or reflect sound. Devices that have only this function are called passive devices.
They constitute the basis for all other additional function modes as described in 5.2.2 to 5.2.4.
5.2.2 Level-dependent hearing protectors
5.2.2.1 General
Level-dependent hearing protectors are designed to provide different attenuation as the external sound
level changes. Their main purpose is to protect against impulsive or intermittent hazardous noise while
allowing situational awareness.
Requirements for level-dependent hearing protectors are specified in EN 352-4 (for earmuffs) and
EN 352-7 (for earplugs).
5.2.2.2 Passive level-dependent hearing protectors
Passive level-dependent hearing protectors use the acoustic properties of carefully designed air ducts
to give different protection at different noise levels. These types of protector are designed to be
effective against very high level single-impulse noises, such as firearms, rather than the continuous
noise or repetitive impulses found in most industrial situations.
5.2.2.3 Sound-restoration level-dependent hearing protectors
Sound-restoration level-dependent hearing protectors incorporate an electronic sound reproduction
system. At low sound pressure levels the sound detected by an external microphone is amplified and
relayed to a loudspeaker inside the earmuff or earplug. As the external sound pressure level increases,
the electronics reduce the gain and control the level of reproduced sound inside the hearing protector.
5.2.3 Active noise reduction (ANR) protectors
These are hearing protectors which incorporate an electronic sound cancelling system to achieve
additional noise attenuation where passive hearing protectors may be less effective. ANR is particularly
effective at low frequencies (50 Hz to 500 Hz).
Requirements for active noise reduction earmuffs are specified in EN 352-5.
5.2.4 Hearing protectors with external audio input
5.2.4.1 General
These devices use a wired or wireless system through which working signals, alarms, messages or
audio entertainment can be relayed. Some products incorporate a system to limit the sound pressure
level.
5.2.4.2 Hearing protector with entertainment audio input
These devices may incorporate a radio receiver set or music player for entertainment or allow audio
input from external devices. It also offers the possibility to communicate warning signals or messages.
Requirements for entertainment audio earmuffs are specified in EN 352-8.
5.2.4.3 Hearing protector with work or safety-related audio input
These devices include wired input or wireless radio receiver and/or two-way radio for work or safety-
related communication. As the information to be received might be crucial for safety, the product
standards impose no limitation on the reproduced sound pressure level at the ear.
Requirements for earmuffs with electrical audio input (for work or safety-related communication) are
specified in EN 352-6.
6 Selection
6.1 Principles
Personal hearing protection should be selected so that, when used correctly and for the entire duration
of exposure, it will eliminate or minimize the risk to hearing.
As there are many different hearing protectors intended for use in a wide range of noise environments
it is important to choose a suitable type. The product shall be checked for regulatory conformance.
Consideration should be given to the factors listed in a) to h). The list is neither exclusive nor
exhaustive:
a) sound attenuation, see 6.2;
b) work environment, see 6.3;
c) essential work related communication, especially speech intelligibility, see 6.4;
d) compatibility with other personal protective equipment (PPE), such as helmets, spectacles, etc., see
6.5;
e) how the hearing protector will be used, see 6.6;
f) special user groups and medical factors, see 6.7;
g) user comfort; and ergonomic requirements, see 6.8;
h) conformity with relevant requirements for incorporated electronics, see 6.9.
The selection procedure should be reviewed at regular intervals to ensure that an effective attenuation
is maintained. When considering all factors in the selection process the most important outcome is that
the hearing protector will be used during the whole time of noise exposure.
6.2 Selection according to sound attenuation
6.2.1 Guide to protection rating
Hearing protectors should be chosen according to the sound attenuation they will provide. Methods to
predict the sound attenuation of hearing protectors are given in 6.2.3.
NOTE It is generally accepted that the risk of hearing damage associated with occupational noise exposure is
low where the daily noise exposure level (L ) is below 80 dB, and insignificant where L is below 75 dB.
EX,8h EX,8h
National regulations or other guidelines may stipulate selection criteria for personal hearing protection
and place limits on sound exposure. Such relevant criteria and limits should be taken into account in
deciding what level of sound attenuation is required.
In general, a hearing protector which provides an effective sound level at the ear (L' ) of between 70
p,A,eq
dB and 80 dB is considered suitable. If the chosen hearing protector provides excessive attenuation,
users are at risk of failing to recognize warning signals and understand essential communications. Users
may also feel isolated from their working environment. The perception of isolation increases as the
sound level effective to the ear decreases.
Workers may be exposed to different noise environments during the working day. It may be possible to
select a single hearing protector which is adequate for all situations likely to be encountered, or it may
be necessary to select more than one type of hearing protector.
EXAMPLE 1 A worker’s only significant noise exposure is to an L of 98 dB, for a total of 30 min per day. His
p,A,eq
L is 86 dB. His employer wishes to minimize the risk to the worker’s hearing, and so aims to provide a hearing
EX,8h
protector that provides an effective sound pressure level at the ear of below 80 dB, ideally between 75 dB and
70 dB. The employer selects a protector that provides a sound attenuation of 26 dB.
EXAMPLE 2 A worker spends the majority of her working day (a total of 6 h) in an environment with an L
p,A,eq
of 94 dB. Her L is around 93 dB. Her employer wishes to reduce the effective L' to at least below 80 dB, and
EX,8h EX,8h
to minimize the risk to the worker’s hearing. The employer rejects a protector that provides a sound attenuation
of 32 dB, as this would reduce the effective sound pressure level at the ear to 62 dB and so risk over-protection.
The employer selects a protector that provides a sound attenuation of 22 dB.
6.2.2 Sound attenuation in practice (Real-world attenuation)
The attenuation afforded by a hearing protector when used under normal working conditions may
differ from that indicated on the device packaging or in the user information. This may be due to factors
including incorrect selection and use (see Clause 7), misuse and poor maintenance. For remarks on
improving field performance see Annex F.
These differences may be overcome by appropriate information, instruction and on-going training in
the use of the product. There are tools available to make individual tests to check the correct fitting.
Some countries have published specific guidance on de-rating the published data in an attempt to
address the issue of attenuation in practice. Refer to your national guidance for further information.
6.2.3 Acoustical selection methods
6.2.3.1 Methods for assessing the sound attenuation of a passive hearing protector for
continuous noise exposure
When selecting a suitable hearing protector, consideration should be given to the characteristics of the
noise and the attenuation data of potentially suitable hearing protectors. The attenuation of most
hearing protectors varies with frequency. To determine if a hearing protector is (acoustically) suitable,
it is necessary to estimate the sound pressure level effective to the ear when the hearing protector is
used. There are four methods of estimating the sound pressure level effective to the ear. These are:
— Octave band method;
— HML method;
— HML check method;
— SNR method.
All four methods are explained in detail in Annex A including worked examples. Table 1 shows the type
of information on workplace noise needed for each estimation method.
Table 1 — Information on workplace noise required for assessing sound attenuation
Estimation method Information required
Octave band method (see A.2) octave band sound pressure level; L / L
p,oct p,oct,eq
HML method (see A.3) A and C-weighted sound pressure level; L and L /
p,A p,C
L and L
p,A,eq p,C,eq
A-weighted sound pressure level, L / L
p,A p,A,eq
HML check method (see A.4)
subjective decision between two noise classes (using
lists of examples of noise sources, see A.4)
SNR method (see A.5) C-weighted sound pressure level, L / L
p,C p,C,eq
For changing noise environments and/or exposure times it may be appropriate to use more than one
type of hearing protector in a working day. If the noise is not continuous but fluctuating or impulsive,
the equivalent level should be calculated or measured. The four estimation methods do not take account
of any de-rating values. Refer to your national guidance for further information on this issue (see 6.2.2).
6.2.3.2 Method for assessing the sound attenuation of a hearing protector for impulsive
sounds
The method described in Annex B is applicable to passive, sound-restoration level-dependent, and ANR
hearing protectors as described in EN 352. At high sound pressure levels non-passive devices operate in
the passive mode. Accordingly the sound attenuation HML data used for the selection is for the passive
mode.
6.2.3.3 Selection method for sound-restoration level-dependent hearing protectors using HML
data
Annex C describes a method to aid the correct selection of a non-passive sound-restoration level-
dependent hearing protector when it is used in a given noise environment. The method is applicable to
both earmuffs and earplugs using HML criterion level data obtained in accordance with EN 352-4 and
EN 352-7 respectively. The method may be suitable for other similar non-passive devices.
The annex determines only whether the hearing protector will reduce the A-weighted sound pressure
level effective to the ear to below the defined limit of 85 dB(A). This annex cannot give the specific level
at the ear and accordingly cannot be used for comparison with the national regulation level L' .
NR
6.2.3.4 Selection method for active noise reduction hearing protectors
Annex D describes a method to aid the correct selection of an active noise reduction hearing protector
when it is used in a given noise environment. The method is applicable to both earmuffs and earplugs
using the total (active plus passive) attenuation data obtained in accordance with EN 352-5. The
method may be suitable for other similar devices.
6.2.3.5 Selection method for hearing protectors with audio input
When there is a need or demand for radio for essential communication or entertainment, hearing
protectors with an audio input are available. These are divided in two types: for entertainment
(listening to a music source) or for safety or work related speech communication. Such devices allow
the user to hear without removing the protector.
The user will be exposed to both the attenuated ambient noise and the audio input signal. Earmuffs with
entertainment audio input conform to EN 352-8. For FM radio products the audio sound pressure level
is limited to 82 dB(A) effective to the ear. For products with entertainment audio input the sound
pressure level is limited to 82 dB(A) for all input signal levels up to the maximum specified by the
manufacturer.
NOTE The sound pressure level can exceed 82 dB(A) for input signal levels higher than those specified by the
manufacturer. To minimize the risk of hazardous exposure it is therefore recommended to select products with
built-in limiter functions.
Where communication is essential, earmuffs should conform to EN 352-6. The audio input is not limited
but the input signal level corresponding to 82 dB(A) effective to the ear should be provided by the
device manufacturer (criterion voltage).
If the contribution of the audio input signal
...