SIST EN ISO 21388:2021

SLOVENSKI STANDARD
oSIST prEN ISO 21388:2021
01-julij-2021
Akustika - Vodenje ustreznosti slušnih pripomočkov(ISO 21388:2020)
Acoustics - Hearing aid fitting management (HAFM) (ISO 21388:2020)
Acoustique - Gestion des appareils de correction auditive (ISO 21388:2020)
Ta slovenski standard je istoveten z: prEN ISO 21388
ICS:
11.180.15 Pripomočki za gluhe osebe in Aids for deaf and hearing
osebe z okvaro sluha impaired people
17.140.01 Akustična merjenja in Acoustic measurements and
blaženje hrupa na splošno noise abatement in general
oSIST prEN ISO 21388:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 21388:2021

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oSIST prEN ISO 21388:2021
INTERNATIONAL ISO
STANDARD 21388
First edition
2020-03
Acoustics — Hearing aid fitting
management (HAFM)
Acoustique — Gestion des appareils de correction auditive
Reference number
ISO 21388:2020(E)
©
ISO 2020

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oSIST prEN ISO 21388:2021
ISO 21388:2020(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Email: copyright@iso.org
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Published in Switzerland
ii © ISO 2020 – All rights reserved

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oSIST prEN ISO 21388:2021
ISO 21388:2020(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3  Terms and definitions . 2
4 Service preconditions. 4
4.1 General . 4
4.2 Educational requirements . 4
4.2.1 General. 4
4.2.2 Requirements for hearing aid professionals . 4
4.2.3 Maintenence of competencies and skills of hearing aid professionals . 5
4.3 Facility requirements . 5
4.3.1 General. 5
4.3.2 Room requirements . 5
4.4 Equipment requirements . 5
4.4.1 General. 5
4.4.2 Audiometric equipment . . 6
4.4.3 Equipment for otoscopy and earmould impressions . 6
4.4.4 Hearing aid programming equipment. 6
4.4.5 Electroacoustic measurement equipment . 6
4.4.6 Maintenance tools . 6
4.4.7 Demonstration samples . 7
4.5 Ethical requirements . 7
4.5.1 General. 7
4.5.2 Professional competence . 7
4.5.3 Relationship with clients . 7
4.5.4 Conflict of interest . 7
4.5.5 Relationship with medical and other health practitioners . 7
4.5.6 Relationship with colleagues . 8
4.5.7 Advertising . 8
5 General stages of HAFM . 8
5.1 General . 8
5.2 Client profile . 9
5.2.1 General. 9
5.2.2 General assessment . 9
5.2.3 Audiological assessment .10
5.2.4 Medical referral .11
5.3 Counselling .11
5.3.1 General.11
5.3.2 Selection of hearing aid system .11
5.4 Hearing aid fitting .11
5.4.1 Ear coupling elements . .11
5.4.2 Pre-setting of hearing aids .12
5.4.3 Setting and fine-tuning of hearing aids .12
5.5 Verification and validation .12
5.6 Post-fitting counselling .13
5.7 Follow-up .13
6 Quality of service .14
6.1 General .14
6.2 Documentation .14
6.3 Client evaluation of services .15
6.4 Customer complaint handling .15
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6.5 Corrective actions .15
Annex A (informative) Minimum competencies of the hearing aid professional (HAP) .16
Annex B (informative) Recommendation for organisation of education and training for
hearing aid professionals (ISCED level 5) .19
Annex C (informative) Fitting room example .21
Annex D (informative) Recommendation on the referral of clients for medical
or other specialist examination and treatment .23
Annex E (informative) Informational counselling to support hearing aid fitting management .24
Annex F (informative) Terminology .27
Bibliography .41
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oSIST prEN ISO 21388:2021
ISO 21388:2020(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 43, Acoustics.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
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Introduction
The World Health Organisation (WHO) estimates that there are 360 million people with hearing
[22]
impairment, approximately 5,3 % of the world population . Hearing aids (HAs) are one of the
[39][40]
most widely-used treatment options for people with a hearing loss . For the proper use of HAs,
hearing aid fitting management (HAFM) is a crucial issue for manufacturers, practitioners, hearing
[39][42][43]
aid professionals and especially for HA users . Individually optimized outcome of HA use is
[42]
supported by comprehensive HA fitting protocols and the impact of “poor fit and comfort” can lead
[43]
to non-compliance, HA return and additional hearing loss with over-amplification. Accordingly, the
whole process of HA fitting should be optimized to achieve functional benefits, user satisfaction and
cost-effectiveness.
Two observations are important to take into account when developing an HAFM standard. Firstly,
[16][44]–[46]
the term "hearing aid fitting" is widely used among service providers and industry sectors.
Secondly, it has potentially conflicting interpretations: while guidelines for HA fitting have been
[17][18][23]–[32][34]–[37][47][48]
written to tackle these issues by various national and professional bodies ,
many jurisdictions are still not covered worldwide and there is a need to promote a more common
understanding of the HA fitting process. It is likely that different understanding of fitting has led to
non-uniform care, outcome variability and, in many cases, dissatisfaction with the use of HAs.
The main purpose of this document is thus to provide a general framework for HAFM including the
pre- and post-fitting stages to make it more explicit and transparent so that all related tasks, including
professional services, administration and financial aspects can be systematized. The overall objective
is to achieve the best possible hearing rehabilitation, which can only be accomplished through adequate
knowledge, training and skills of the professional and a systematic approach to HA fitting in close
collaboration with the client. The general framework of HAFM in this document is divided into six
stages (client profile, counselling, hearing aid fitting, verification and validation, post-fitting counseling,
and follow-up) based on the common practices of hearing aid professionals, and as recommended by
various pre-existing guidelines.
By dividing the hearing aid fitting process into stages, HAFM service providers can systematically
identify and administer the service components needed for high service quality, user satisfaction,
client-centered services, client self-efficacy and compliance rates with HAs (e.g. consistently using
HAs and attending follow-up appointments). The stages focus on the components of the framework to
achieve high rehabilitation outcomes such as communication skills, speech intelligibility, perception of
the acoustic environment, comfort for the HA users and sound quality. In addition, this document can
be a basis for making cost assessments for each stage or component, which can help improve public
health funding systems. Another possible application is to use this document as a minimum basis for
the development of professional training programs in HAFM.
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oSIST prEN ISO 21388:2021
INTERNATIONAL STANDARD ISO 21388:2020(E)
Acoustics — Hearing aid fitting management (HAFM)
1 Scope
This document applies to hearing aid fitting management (HAFM) services offered by hearing aid
professionals (HAP) when providing benefit for their clients. The provision of hearing aids relies on
the knowledge and practices of a hearing aid professional, to ensure the proper fitting and adequate
service in the interest of the client with hearing loss.
This document specifies general processes of HAFM from the client profile to the follow-up through
administering, organising and controlling hearing aid fitting through all stages. It also specifies
important preconditions such as education, facilities and systems that are required to ensure proper
services.
The focus of this document is the services offered to the majority of adult clients with hearing
impairment. It is recognized that certain populations with hearing loss such as children, persons with
other disabilities or persons with implantable devices can require services outside the scope of this
document. This document generally applies to air conduction hearing aids and for the most part also to
bone conduction devices.
Hearing loss can be a consequence of serious medical conditions. Hearing aid professionals are not in
a position to diagnose or treat such conditions. When assisting clients seeking hearing rehabilitation
without prior medical examination, hearing aid professionals are expected to be observant of symptoms
of such conditions and refer to proper medical care.
Further to the main body of the document, which specifies the HAFM requirements and processes,
several informative annexes are provided. Appropriate education of hearing aid professionals is vital
for exercising HAFM. Annex A defines the competencies required for the HAFM processes. Annex B
offers a recommended curriculum for the education of hearing aid professionals. Annex C is an example
of an appropriate fitting room. Annex D gives guidance on the referral of clients for medical or other
specialist examination and treatment. Annex E is a recommendation for important information to be
exchanged with the client during the process of HAFM. Annex F is a comprehensive terminology list
offering definitions of the most current terms related to HAFM.
It is the intention that these annexes be helpful to those who wish to deliver HAFM of the highest quality.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 8253-1, Acoustics — Audiometric test methods — Part 1: Pure-tone air and bone conduction audiometry
ISO 8253-2, Acoustics — Audiometric test methods — Part 2: Sound field audiometry with pure-tone and
narrow-band test signals
ISO 8253-3, Acoustics — Audiometric test methods — Part 3: Speech audiometry
IEC 60118-7, Electroacoustics — Hearing aids — Part 7: Measurement of the performance characteristics
of hearing aids for production, supply and delivery quality assurance purposes
IEC 60645-1:2017, Electroacoustics — Audiometric equipment — Part 1: Equipment for pure-tone and
speech audiometry
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IEC 60645-5, Electroacoustics — Audiometric equipment — Part 5: Instruments for the measurement of
aural acoustic impedance/admittance
IEC 61669, Electroacoustics — Measurement of real-ear acoustic performance characteristics of hearing aids
International Standard Classification of Education, ISCED. United Nations Educational, Scientific
and Cutural Oganization, 2011, ISBN 978-92-9189-123-8, http:// uis .unesco .org/ sites/ default/ files/
documents/ international -standard -classification -of -education -isced -2011 -en .pdf
3  Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
auditory dynamic range
difference between the hearing (3.7) threshold and the uncomfortable loudness level (UCL)
3.2
client
person with hearing loss (3.8) being serviced by a HAP (3.13)
3.3
client profile
comprehensive record of a client's (3.2) auditory functionality, social situation, activity opportunities,
needs and expectations as well as a client’s audiological and medical history
3.4
ear impression
representation of the three-dimensional geometry of the relevant part of the concha and ear canal
3.5
fine-tuning
adjustment of the hearing aid system (3.10) to best match the needs and preferences of the client (3.2)
3.6
fitting system
set of devices typically comprising a computer, fitting software and a programming interface used to
adjust hearing aids (3.9)
3.7
hearing
manner in which a person detects, discriminates, identifies and cognitively processes sounds
3.8
hearing loss
reduction of the hearing (3.7) ability
3.9
hearing aid
wearable electroacoustic instrument intended to process sounds in order to compensate for hearing
loss (3.8)
Note 1 to entry: Hearing aids are medical devices and comply with the requirements of IEC 60601-2-66.
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3.10
hearing aid system
customized structure consisting of one or two hearing aids (3.9), earmoulds and related components
such as a remote control or interfaces to other information or communication systems
3.11
hearing aid fitting
systematic procedure for individualizing and optimizing a hearing aid system (3.10) to compensate for
hearing loss (3.8)
3.12
hearing aid fitting management
HAFM
systematic process to administer, organise and control hearing aid fitting (3.11) through all stages
3.13
hearing aid professional
HAP
person who is appropriately trained and has proven competency in professionally assessing hearing,
selecting, fitting and delivering hearing aid systems (3.10) and rehabilitation services to persons with
hearing loss (3.8)
3.14
hearing rehabilitation
systematic process for improving functional hearing abilities and communication skills through hearing
aid fitting (3.11), counselling, instruction, education, training and developing listening skills
Note 1 to entry: The term “habilitation” includes all rehabilitation processes with additional interventions to
develop listening, speech and language skills for prelingually deafened individuals such as children which are
outside the scope of this document.
3.15
maximum output
maximum sound pressure level at the output of a hearing aid (3.9) as adjusted by the HAP (3.13)
3.16
pre-setting of hearing aids
configuration and adjustment of a hearing aid (3.9) using a prescriptive rule and relevant audiological data
3.17
verification
provision of objective evidence that a given item fulfils specified requirements
Note 1 to entry: In the field of hearing aid fitting (3.11), the verification usually means evaluating physical,
electroacoustic and psycho-acoustic aspects of a hearing aid fitting by presenting signals to hearing aids (3.9) in a
hearing aid test box or a real-ear or by using functional gain measurement in accordance with ISO 8253-2.
[SOURCE: ISO/IEC Guide 99:2007, 2.44, modified - Examples removed, original Notes to entry replaced
with Note 1 to entry.]
3.18
validation
verification (3.17), where the specified requirements are adequate for an intended use
Note 1 to entry: In the field of hearing aid fitting (3.11), the verification usually means a comprehensive evaluation
of the user benefits of a hearing aid fitting using methods which include speech audiometry and subjective
response questionnaires.
[SOURCE: ISO/IEC Guide 99:2007, 2.45, modified - Example removed, Note 1 to entry added.]
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4 Service preconditions
4.1 General
For quality service provision, the following preconditions shall be fulfilled:
— educational requirements;
— facility requirements;
— equipment requirements;
— ethical requirements.
Further preconditions are given by local applicable laws and regulations.
4.2 Educational requirements
4.2.1 General
The competencies of persons delivering the service are essential to the quality of service and should be
rooted in appropriate education from recognized educational institutions and organisations as well as
relevant practical skills obtained in a structured process. Ongoing education is required as it is vital to
maintaining the competencies, skill levels and knowledge needed for best practice.
In general, delegation of tasks to staff without the required education should not be permitted. More than
one type of staff can perform certain tasks in accordance with their specific educational background
following national or regional regulations. The overall responsibility of the service provision shall rest
with a HAP with the education specified in 4.2.2.
In order to facilitate the acquisition of practical skills, practices may include trainees from educational
programs in their staff. Services performed by trainees shall take place under the supervision of
a qualified HAP who shall be present at the facilities and who remains responsible for all activities
carried out by the trainee.
4.2.2 Requirements for hearing aid professionals
A minimum education level 5 according to the International Standard Classification of Education,
ISCED, or equivalent is required in order to perform all stages of hearing aid fitting management. A
level 6 education is recommended.
It is recommended that the educational program includes the following academic topics: basic
mathematics and science including acoustics, anatomy and physiology, psychology and linguistics,
audiology, hearing aid technology, hearing rehabilitation processes, hearing aid fitting.
The following practical skills should be obtained through training: client interaction, audiometric
measurements, earmould management, hearing aid programming, fitting verification and validation,
hearing aid modification and repair.
Suggestions for minimum competencies of the HAP and a suitable education program are given in
Annexes A and B, respectively.
Any HAP shall have proven minimal competencies through t
...