ISO/PRF 29061-5

Road vehicles — Methods and criteria for usability evaluation of child restraint systems and their interface with vehicle anchorage systems — Part 5: Installation and securing of child in a booster system

ISO 29061-5:2017 provides criteria for judgement of usability of booster seat child restraint systems (CRS) when installing them and securing a child. ISO 29061-5:2017 provides criteria for judgement of: - ease of availability of instructions; - clarity of instruction manual and labelling; and - ease of use of design related features of the CRS related to the installation in a vehicle. The procedure can also be used for evaluation of vehicle integrated booster systems. NOTE Although ISOFIX is defined in the original "ISOFIX" standard (ISO 13216‑1) to be a rigid system, the term "ISOFIX" in this document is extended to include flexible CRS attachments (LATCH, UAS).

Véhicules routiers — Méthodes et critères pour l'évaluation de la facilité d'utilisation des systèmes de retenue pour enfants, et leurs interfaces avec les systèmes d'ancrage dans le véhicule — Partie 5: Installation et fixation d'un enfant dans un système de réhausseur

General Information

• Status: Not Published
• ICS: 43.040.80 - Crash protection and restraint systems
• Technical Committee: ISO/TC 22/SC 36 - Safety and impact testing
• Drafting Committee: ISO/TC 22/SC 36 - Safety and impact testing
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 14-Nov-2025
• Completion Date: 13-Dec-2025

Relations

• Revises: ISO 29061-5:2017 - Road vehicles — Methods and criteria for usability evaluation of child restraint systems and their interface with vehicle anchorage systems — Part 5: Installation and securing of child in a booster system
• Effective Date: 06-Jun-2022

Standards Content (Sample)

International
Standard
ISO 29061-5
Second edition
Road vehicles — Methods and
criteria for usability evaluation of
child restraint systems and their
interface with vehicle anchorage
systems —
Part 5:
Installation and securing of child in
a booster system
Véhicules routiers — Méthodes et critères pour l'évaluation de la
facilité d'utilisation des systèmes de retenue pour enfants, et leurs
interfaces avec les systèmes d'ancrage dans le véhicule —
Partie 5: Installation et fixation d'un enfant dans un système de
réhausseur
PROOF/ÉPREUVE
Reference number
ISO 29061-5:2025(en) © ISO 2025

ISO 29061-5:2025(en)
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
PROOF/ÉPREUVE
ii
ISO 29061-5:2025(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Usability evaluation procedure and scoring principles . 4
4.1 Evaluation procedure .4
4.2 Scoring system . .4
5 Usability evaluation forms . 5
Annex A (informative) Recommendations regarding scoring and assessment . 19
Annex B (informative) Example usability rating classes .20
Bibliography .21
PROOF/ÉPREUVE
iii
ISO 29061-5:2025(en)
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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 22, Road vehicles, Subcommittee SC 36, Safety
and impact testing.
This second edition cancels and replaces the first edition (ISO 29061-5:2017), which has been technically
revised.
The main changes are as follows:
— reviewed terminology to cover technology and regulation updates since the first edition;
— editorial review.
A list of all parts in the ISO 29061 series can be found on the ISO website.
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.
PROOF/ÉPREUVE
iv
ISO 29061-5:2025(en)
Introduction
The usability of a child restraint system (CRS) in terms of ease of:
— installation of CRSs in various vehicles; and
— day-to-day use with a child (e.g. securing, harnessing, adaption for a growing child)
is of utmost importance to ensure that a CRS is used properly in accordance with the manufacturer's
intentions, and to ensure that a correctly installed CRS will provide the best possible protection in a
crash situation. An international agreement on usability criteria and measurements is beneficial for both
consumers and manufacturers.
The aim of this document is to provide a usability evaluation system for installation of booster system CRSs,
when installing them and securing a child, to promote improved design for an easy and correct use.
It provides child restraint and vehicle manufacturers with a tool for the assessment of the usability of new
and current systems. At the same time, it provides consumers (parents and caregivers) with usability
information on the key features related to the proper use of the attachment system and assist them in
selecting child restraints and vehicles that are easy to use properly.
The ISO usability evaluation system has been developed with participation from, and considering the
experiences from, usability rating systems of Canada (Transport Canada and ICBC), USA (NHTSA, IIHS) and
the European Union (EU) (NPACS and consumer rating programmes, such as ICRT, ADAC).
PROOF/ÉPREUVE
v
International Standard ISO 29061-5:2025(en)
Road vehicles — Methods and criteria for usability evaluation
of child restraint systems and their interface with vehicle
anchorage systems —
Part 5:
Installation and securing of child in a booster system
1 Scope
This document provides criteria for judgement of usability of booster seat child restraint systems (CRSs)
when installing them and securing a child.
This document provides criteria for judgement of:
— ease of availability of instructions;
— clarity of instruction manual and labelling; and
— ease of use of design related features of the CRS related to the installation in a vehicle.
The procedure can also be used for evaluation of vehicle integrated booster systems.
NOTE 1 CRS includes enhanced child restraint systems (ECRS) according to UN Regulation No. 129.
NOTE 2 Although ISOFIX is defined in the original “ISOFIX” standard (ISO 13216-1) to be a rigid system, the term
“ISOFIX” in this document is extended to include flexible CRS attachments (e.g. LATCH in USA, UAS in Canada).
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
audible
capable of being heard in normal environmental conditions
3.2
booster system
any kind of belt-positioning child restraint system (CRS) (3.3) where the vehicle seat belt is the primary
restraint for the child
PROOF/ÉPREUVE
ISO 29061-5:2025(en)
3.3
child restraint system
CRS
free-standing device intended to provide child vehicle occupants with an approved restraint
Note 1 to entry: CRSs comprise various categories such as car beds, infant-only restraints, toddler seats (forward or
rearward-facing), booster cushions, and booster seats. Combination products (multi modes CRS) cover two or more of
these product categories.
3.4
ISOFIX
system for the connection of child restraint systems (CRSs) (3.3) to vehicles, which has two rigid anchorages
(3.5) in a vehicle seating position located near the seat bight, corresponding rigid attachments (3.7) on the
CRS, and a means to limit the pitch rotation of the CRS (3.3)
Note 1 to entry: In this document, the term ISOFIX is extended to include flexible CRS attachments, e.g. LATCH (Lower
Anchorages and Tethers for CHildren) in USA and UAS (Universal Anchorage System) in Canada.
[SOURCE: ISO 13216-1:1999, 3.6, modified — Note 1 to entry has been added.]
3.5
anchorage
part of the universal interface provided in a vehicle
Note 1 to entry: See also ISOFIX anchorages (3.6), and top tether anchorage (3.11.1).
3.6
ISOFIX anchorage
one of two (2) prescribed 6 mm diameter round horizontal bars, in accordance with ISO 13216-1:1999,
provided at a vehicle seating position and extending from vehicle seat bight or seat structure to accept and
restrain a child restraint system (CRS) (3.3) with prescribed attachments (3.7)
Note 1 to entry: Anchorages (3.5) may be rigid or semi-rigid according to ISO 13216-1:1999, Annex A.
3.7
attachment
part of the universal interface provided with the child restraint system (CRS) (3.3)
Note 1 to entry: See also ISOFIX attachments (3.8).
3.8
ISOFIX attachment
one of two (2) prescribed connections, in accordance with ISO 13216-1:1999, extending from the child
restraint system (CRS) (3.3) structure, and compatible with an anchorage (3.5).
Note 1 to entry: Attachments (3.7) may be rigid or non-rigid (flexible) according to ISO 13216-1:1999, Annex B.
3.9
anti-rotational device
device intended to restrict forward or rearward rotation of a child restraint system (CRS) (3.3)
3.9.1
primary anti-rotational device
device intended to restrict forward rotation of a child restraint system (CRS) (3.3)
EXAMPLE Top tether (3.11) or support leg (3.10).
PROOF/ÉPREUVE
ISO 29061-5:2025(en)
3.10
support leg
type of anti-rotational device (3.8) comprising a permanent attachment to a child restraint system (CRS) (3.3),
creating a compressive load path between the CRS and a vehicle structure (for example, the vehicle floor) to
prevent or reduce forward rotation of the CRS.
Note 1 to entry: A support leg can be adjustable.
3.11
top tether
tether strap (or equivalent) attached at or near the top of a child restraint system (CRS) (3.3), incorporating a
device to enable it to be connected to a top tether anchorage (3.11.1)
3.11.1
top tether anchorage
device, such as a ring, bar, bracket, or webbing loop, and its underlying structure, either user-ready or
aftermarket-installed, to which a top tether (3.11) can be attached
3.11.2
top tether strap
webbing strap which extends from the top of a child restraint system (CRS) (3.3) to the top tether anchorage
(3.11.1) and which is equipped with an adjustment device, a tension-relieving device and a top tether (3.11)
connector (3.12)
[SOURCE: ISO 13216-2:2004, 3.3]
3.12
connector
connecting and locking device to the universal interface, provided with the CRS (3.3), and part of the
attachment (3.7)
3.13
single action
operation that can be completed without the need to undertake a secondary action
EXAMPLE A single action includes tightening a strap by pulling it without the need to release a locking system or
attaching to an anchorage (3.5) without the need to depress the seat cushion.
3.14
slack
looseness of an adjustable strap that is likely to affect the performance of the child restraint system (CRS)
(3.3) adversely
3.15
hidden slack
unintended looseness of an adjustable strap that is likely to affect the performance of the child restraint
system (CRS) (3.3) adversely, and that cannot be easily detected
3.16
usability
extent to which a vehicle or child restraint system (CRS) (3.3) is capable of being used and is convenient and
practical in use (separately or combined)
3.17
vehicle seat belt positioning device
device intended to maintain the appropriate shoulder strap in position on the child's torso
PROOF/ÉPREUVE
ISO 29061-5:2025(en)
4 Usability evaluation procedure and scoring principles
4.1 Evaluation procedure
This document provides a procedure to evaluate the usability of booster systems, i.e. booster seats with
or without seatbacks, including booster seats integrated in the vehicle seat, and the securing of a child in
the seat. The procedure evaluates the ease of availability of instruction, clarity of instruction manual and
labelling, and the ease of use of design-related features of the CRS related to the installation in a vehicle.
The assessment is done in three steps:
— a separate assessment of the booster system;
— a usability assessment when installing the booster system in specified vehicle seating positions; and
— securing a child or child dummy in the booster system.
The evaluation takes into consideration the various modes of installation and conversions between
installation modes. The usability protocol, consisting of two forms, is intended to be objective and repeatable.
The evaluation is most easily accomplished using a team of two people having basic knowledge of child
restraints and being familiar with the technical terms used. However, they should preferably be unfamiliar
with the CRS model to be evaluated. The procedure takes about 30 min.
The necessary materials include:
— the usability evaluation form (in either paper or electronic format);
— the vehicle owner’s manual;
— the CRS manual, including instruction video if applicable;
— a force gauge for measuring belt tension.
A copy of the terms and definitions from this document can also be helpful.
Initially, the booster system shall be in the condition as supplied to the consumer. The evaluation process
includes all the steps, including assembly, to complete the installation.
Unpacking the CRS, removing the box and plastic protections, detaching the handbook, etc. shall be disregarded
in the evaluation, but other initial one-time preparations are considered and assessed in the forms.
The mode of use for the booster system and the seating position in the vehicle shall be determined in advance
and documented in the evaluation form.
The evaluation process first addresses the labels and instructions, then the ease of positioning the booster
seat followed by securing the child or child dummy, and finally the removal of the CRS. Installation and
removal does not apply to integrated systems.
4.2 Scoring system
The scoring system consists of a good/average/poor rating (scored with 3/1/0 points) of each item assessed,
and an importance rating A/B/C (scored with 3/2/1 points) for each item. For each assessment, the scoring of
the above are multiplied. A maximum score for a "Good" solution on an item with "A" importance is 9 points.
In this document, “average” means “mid-level” and shall not be perceived as a statistical average between
good and poor.
The maximum possible score will depend on the features of the booster system. Different products can have
different maximum possible scores, and therefore, comparisons of the raw number of total points would not
be appropriate. The final rating consists of a total number of points that shall be expressed as a percentage
PROOF/ÉPREUVE
ISO 29061-5:2025(en)
of the maximum possible score for the particular conditions. See also further recommendations given in
Annex A. An example of usability rating classes is given in Annex B.
In addition, in some instances the rating will result in a total poor rating (or fail) if the product evaluated
does not score either a “good” or “average” in the most crucial questions of this rating. These instances are
identified in the evaluation sheets in the “notes” column against the relevant questions.
5 Usability evaluation forms
The following are the usability evaluation forms:
— Form 1: Booster system, separate evaluation;
— Form 2: interface – installing the booster system and securing the child;
To enhance the value and applicability of this document, the forms are also provided in a revisable [MS
1)
Excel ] format. These forms are provided at the following URL: https:// standards .iso .org/ iso/ 29061/ -5/ ed
-2/ en .
1) MS Excel is an example of a suitable product available commercially. This information is given for the convenience of
users of this document and does not constitute an endorsement by ISO of this product.
PROOF/ÉPREUVE
ISO 29061-5:2025(en)
PROOF/ÉPREUVE
Form 1: Booster system, separate evaluation
Date of evaluation Evaluated by Test no.

Child restraint system evalu-  Backless booster  Booster seat with seat-  Other (convertible/combination,
 Integrated booster system
ated cushion back etc.)
Booster system using vehicle
 Rigid attachments  Flexible attachments  Top tether  Support leg
ISOFIX anchorages
Manufacturer
Child seat make/brand and
model Booster system features:
Country/area of use  Multiple modes CRS (2-in-1)  Multiple modes CRS (3-in-1)
 Booster system using ISOFIX
a
Certification/ type approval no. attachment: evaluated  with /  without ISOFIX
Production no. (serial no./SAI  Booster system using top evaluated  with /  without top
no., etc.) tether attachment: tether
Date of manufacturing, yyyy-  Booster system with remov-
mm-dd able seatback:  seatback on  seatback off

Appropriate child size range
for this mode according to
instruction manual Mass range (where applicable) (kg): Height range (cm): Age range (months or years):
a
Where applicable.
ISO 29061-5:2025(en)
PROOF/ÉPREUVE
Form 1.1: CRS instructions and labels
Good Average Poor Importance N/A Notes
Do CRS instructions clearly show Illustrated clearly with CRS in Pictures plus written Method missing, partially illus-
how to prepare and/or install the vehicle seat. Visually obvious, instructions are provid- trated, or no illustrations. CRS
CRS in the vehicle (in t
...

ISO/DISPRF 29061-5:2025(en)
ISO/TC 22/SC 36
Secretariat: AFNOR
Date: 2025-07-1511-13
Road vehicles — Methods and criteria for usability evaluation of
child restraint systems and their interface with vehicle anchorage
systems — —
Part 5:
Installation and securing of child in a booster system
Véhicules routiers — Méthodes et critères pour l'évaluation de la facilité d'utilisation des systèmes de retenue
pour enfants, et leurs interfaces avec les systèmes d'ancrage dans le véhicule —Partie 5: Installation et fixation
d'un enfant dans un système de réhausseur
Partie 5: Installation et fixation d'un enfant dans un système de réhausseur
PROOF
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
EmailE-mail: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
ISO/DISPRF 29061-5:2025(en)
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Usability evaluation procedure and scoring principles . 4
4.1 Evaluation procedure . 4
4.2 Scoring system . 5
5 Usability evaluation forms . 5
Annex A (informative) Recommendations regarding scoring and assessment . 24
Annex B (informative) Example usability rating classes . 25
Bibliography . 26

iii
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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 22, Road vehicles, Subcommittee SC 36, Safety
and impact testing.
This second edition cancels and replaces the first edition (ISO 29061-5:2017), which has been technically
revised.
The main changes are as follows:
— — reviewed terminology to cover technology and regulation updates since the first edition;
— — editorial review.
A list of all parts in the ISO 29061 series can be found on the ISO website.
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.
iv
ISO/DISPRF 29061-5:2025(en)
Introduction
The usability of a child restraint system (CRS) in terms of ease of:
— — installation of CRSs in various vehicles; and
— — day-to-day use with a child (e.g. securing, harnessing, adaption for a growing child)
is of utmost importance to ensure that a CRS is used properly in accordance with the manufacturer's
intentions, and to ensure that a correctly installed CRS will provide the best possible protection in a crash
situation. An international agreement on usability criteria and measurements is beneficial for both consumers
and manufacturers.
The aim of this document is to provide a usability evaluation system for installation of booster system CRSs,
when installing them and securing a child, to promote improved design for an easy and correct use.
It provides child restraint and vehicle manufacturers with a tool for the assessment of the usability of new and
current systems. At the same time, it provides consumers (parents and caregivers) with usability information
on the key features related to the proper use of the attachment system and assist them in selecting child
restraints and vehicles that are easy to use properly.
The ISO usability evaluation system has been developed with participation from, and considering the
experiences from, usability rating systems of Canada (Transport Canada and ICBC), USA (NHTSA, IIHS) and
the European Union (EU) (NPACS and consumer rating programmes, such as ICRT, ADAC).
v
DRAFT International Standard ISO/DIS 29061-5:2025(en)

Road vehicles — Methods and criteria for usability evaluation of child
restraint systems and their interface with vehicle anchorage systems
— —
Part 5:
Installation and securing of child in a booster system
1 Scope
This document provides criteria for judgement of usability of booster seat child restraint systems (CRSs) when
installing them and securing a child.
This document provides criteria for judgement of:
— — ease of availability of instructions;
— — clarity of instruction manual and labelling; and
— — ease of use of design related features of the CRS related to the installation in a vehicle.
The procedure can also be used for evaluation of vehicle integrated booster systems.
NOTE 1 CRS includes enhanced child restraint systems (ECRS) according to UN Regulation No. 129.
NOTE 2 Although ISOFIX is defined in the original “ISOFIX” standard (ISO 13216--1) to be a rigid system, the term
“ISOFIX” in this document is extended to include flexible CRS attachments (e.g. LATCH in USA, UAS in Canada).
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— — ISO Online browsing platform: available at https://www.iso.org/obp
— — IEC Electropedia: available at https://www.electropedia.org/
3.1 3.1
audible
capable of being heard in normal environmental conditions
3.2 3.2
booster system
any kind of belt-positioning child restraint system (CRS) (3.3 (3.3)) where the vehicle seat belt is the primary
restraint for the child
3.3 3.3
child restraint system
CRS
free-standing device intended to provide child vehicle occupants with an approved restraint
Note 1 to entry: CRSs comprise various categories such as car beds, infant-only restraints, toddler seats (forward or
rearward-facing), booster cushions, and booster seats. Combination products (multi modes CRS) cover two or more of
these product categories.
3.4 3.4
ISOFIX
system for the connection of child restraint systems (CRSs) (3.3CRS (3.3)) to vehicles, which has two rigid
anchorages (3.5) in a vehicle seating position located near the seat bight, corresponding rigid attachments
(3.7) on the CRS, and a means to limit the pitch rotation of the CRS (3.3(3.3))
Note 1 to entry: In this document, the term ISOFIX is extended to include flexible CRS attachments, e.g. LATCH (Lower
Anchorages and Tethers for CHildren) in USA and UAS (Universal Anchorage System) in Canada.
[SOURCE: ISO 13216-1:1999, 3.6, modified — Note 1 to entry has been added.]
3.5 3.5
anchorage
part of the universal interface provided in a vehicle
Note 1 to entry: See also ISOFIX anchorages (3.6(3.6),), and top tether anchorage (3.11.1(3.11.1).).
3.6 3.6
ISOFIX anchorage
one of two (2) prescribed 6 mm diameter round horizontal bars, in accordance with ISO 13216-1:1999,
provided at a vehicle seating position and extending from vehicle seat bight or seat structure to accept and
restrain a child restraint system (CRS) (3.3 (3.3)) with prescribed attachments (3.7(3.7))
Note 1 to entry: Anchorages (3.5) may be rigid or semi-rigid according to Annex A of ISO 13216-1:1999, Annex A.
3.7 3.7
attachment
part of the universal interface provided with the child restraint system (CRS) (3.3 (3.3))
Note 1 to entry: See also ISOFIX attachments (3.8(3.8).).
3.8 3.8
ISOFIX attachment
one of two (2) prescribed connections, in accordance with ISO 13216-1:1999, extending from the child
restraint system (CRS) (3.3 (3.3)) structure, and compatible with an anchorage (3.5(3.5).).
Note 1 to entry: Attachments (3.7) may be rigid or non-rigid (flexible) according to Annex B of ISO 13216-1:1999, Annex
B.
3.9 3.9
anti-rotational device
device intended to restrict forward or rearward rotation of a child restraint system (CRS) (3.3 (3.3))
ISO/DISPRF 29061-5:2025(en)
3.9.1 3.9.1
primary anti-rotational device
device intended to restrict forward rotation of a child restraint system (CRS) (3.3 (3.3))
EXAMPLE Top tether (3.11) or support leg (3.10.).
3.10 3.10
support leg
type of anti-rotational device (3.8) comprising a permanent attachment to a child restraint system (CRS) (3.3
(3.3),), creating a compressive load path between the CRS (3.3) and a vehicle structure (for example, the
vehicle floor) to prevent or reduce forward rotation of the CRS (3.3).
Note 1 to entry: A support leg can be adjustable.
3.11 3.11
top tether
tether strap (or equivalent) attached at or near the top of a child restraint system (CRS) (3.3 (3.3),),
incorporating a device to enable it to be connected to a top tether anchorage (3.11.1(3.11.1))
3.11.1 3.11.1
top tether anchorage
device, such as a ring, bar, bracket, or webbing loop, and its underlying structure, either user-ready or
aftermarket-installed, to which a top tether (3.11(3.11)) can be attached
3.11.2 3.11.2
top tether strap
webbing strap which extends from the top of a child restraint system (CRS) (3.3 (3.3)) to the top tether
anchorage (3.11.1(3.11.1)) and which is equipped with an adjustment device, a tension-relieving device and
a top tether (3.11(3.11) )connector (3.12)
[SOURCE: ISO 13216-2:2004, 3.3.]]
3.12 3.12
connector
connecting and locking device to the universal interface, provided with the CRS (3.3(3.3),), and part of the
attachment (3.7(3.7))
3.13 3.13
single action
operation that can be completed without the need to undertake a secondary action
EXAMPLE A single action includes tightening a strap by pulling it without the need to release a locking system or
attaching to an anchorage (3.5) without the need to depress the seat cushion.
3.14 3.14
slack
looseness of an adjustable strap that is likely to affect the performance of the child restraint system (CRS) (3.3
(3.3)) adversely
3.15 3.15
hidden slack
unintended looseness of an adjustable strap that is likely to affect the performance of the child restraint system
(CRS) (3.3CRS (3.3)) adversely, and that cannot be easily detected
3.16 3.16
usability
extent to which a vehicle or child restraint system (CRS) (3.3(3.3)) is capable of being used and is convenient
and practical in use (separately or combined)
3.17 3.18
vehicle seat belt positioning device
device intended to maintain the appropriate shoulder strap in position on the child's torso
4 Usability evaluation procedure and scoring principles
4.1 Evaluation procedure
This document provides a procedure to evaluate the usability of booster systems, i.e. booster seats with or
without seatbacks, including booster seats integrated in the vehicle seat, and the securing of a child in the seat.
The procedure evaluates the ease of availability of instruction, clarity of instruction manual and labelling, and
the ease of use of design-related features of the CRS related to the installation in a vehicle.
The assessment is done in three steps:
— — a separate assessment of the booster system;
— — a usability assessment when installing the booster system in specified vehicle seating positions; and
— — securing a child or child dummy in the booster system.
The evaluation takes into consideration the various modes of installation and conversions between
installation modes. The usability protocol, consisting of two forms, is intended to be objective and repeatable.
The evaluation is most easily accomplished using a team of two people having basic knowledge of child
restraints and being familiar with the technical terms used. However, they should preferably be unfamiliar
with the CRS model to be evaluated. The procedure takes about 30 min.
The necessary materials include:
— — the usability evaluation form (in either paper or electronic format);
— — the vehicle owner’s manual;
— — the CRS manual, including instruction video if applicable;
— — a force gauge for measuring belt tension.
A copy of the terms and definitions from this document can also be helpful.
Initially, the booster system shall be in the condition as supplied to the consumer. The evaluation process
includes all the steps, including assembly, to complete the installation.
Unpacking the CRS, removing the box and plastic protections, detaching the handbook, etc. shall be
disregarded in the evaluation, but other initial one-time preparations are considered and assessed in the
forms.
The mode of use for the booster system and the seating position in the vehicle shall be determined in advance
and documented in the evaluation form.
ISO/DISPRF 29061-5:2025(en)
The evaluation process first addresses the labels and instructions, then the ease of positioning the booster
seat followed by securing the child or child dummy, and finally the removal of the CRS. Installation and
removal does not apply to integrated systems.
4.2 Scoring system
The scoring system consists of a good/average/poor rating (scored with 3/1/0 points) of each item assessed,
and an importance rating A/B/C (scored with 3/2/1 points) for each item. For each assessment, the scoring
of the above are multiplied. A maximum score for a "Good" solution on an item with "A" importance is 9 points.
In this document, “average” means “mid-level” and shall not be perceived as a statistical average between good
and poor.
The maximum possible score will depend on the features of the booster system. Different products can have
different maximum possible scores, and therefore, comparisons of the raw number of total points would not
be appropriate. The final rating consists of a total number of points that shall be expressed as a percentage of
the maximum possible score for the particular conditions. See also further recommendations given in
Annex AAnnex A. Example. An example of usability rating classes is given in Annex BAnnex B.
In addition, in some instances the rating will result in a total poor rating (or fail) if the product evaluated does
not score either a “good” or “average” in the most crucial questions of this rating. These instances are identified
in the evaluation sheets in the “notes” column against the relevant questions.
5 Usability evaluation forms
The following are the usability evaluation forms:
— — Form 1: Booster system, separate evaluation;
— — Form 2: interface – installing the booster system and securing the child;
To enhance the value and applicability of this document, the forms are also provided in a revisable [MS
1 1)
Excel ] ] format. These forms are provided at the following URL: https://standards.iso.org/iso/29061/-5/ed-
2/en.
MS Excel is an example of a suitable product available commercially. This information is given for the convenience of
users of this document and does not constitute an endorsement by ISO of this product.
1)
MS Excel is an example of a suitable product available commercially. This information is given for the convenience of
users of this document and does not constitute an endorsement by ISO of this product.
ISO/DIS 29061-5:2025(en)
Form 1: Booster system, separate evaluation
Date of evaluation  Evaluated by  Test no.

☐ Backless booster
Child restraint system evaluated ☐ Booster seat with seatback ☐ Integrated booster system ☐ Other (convertible/combination, etc.)
cushion
Booster system using vehicle
☐ Rigid attachments ☐ Flexible attachments ☐ Top tether ☐ Support leg
ISOFIX anchorages
Manufacturer
Child seat make/brand and
model  Booster system features:
Country/area of use  ☐ Multiple modes CRS (2-in-1) ☐ Multiple modes CRS (3-in-1)
☐ Booster system using ISOFIX
a
Certification/ type approval no.  attachment: evaluated ☐ with / ☐ without ISOFIX
Production no. (serial no./SAI no., ☐ Booster system using top
evaluated ☐ with / ☐ without top tether
etc.)  tether attachment:
Date of manufacturing, yyyy-mm- ☐ Booster system with
dd  removable seatback: ☐ seatback on ☐ seatback off

Appropriate child size range for
this mode according to
instruction manual Mass range (where applicable) (kg): Height range (cm): Age range (months or years):
a Where applicable.
ISO/DIS 29061-5:2025(en)
Form 1.1: CRS instructions and labels
Good Average Poor Importance N/A Notes
Do CRS instructions clearly show how Illustrated clearly with CRS in Pictures plus written Method missing, partially
to prepare and/or install the CRS in vehicle seat. Visually obvious, instructions are provided. illustrated, or no illustrations. CRS
the vehicle (in this mode)? able to use with pictures only. Labels on CRS are non self- shown without a vehicle seat. Only
1.1.1 Labels on CRS self-explanatory, explanatory, or viewable from written instructions provided (can
or not necessary to prepare. one direction only. also be non-self-explanatory
Illustrative video provided pictures) or nothing shown.
(included or through web link).
Labels on CRS ☐ ☐ ☐ A ☐
☐ ☐ ☐ ☐
Instruction manual C
Do CRS instructions clearly show how Illustrated clearly with no need  Belt routing label not next to
to route the vehicle belt and how to to read the text to route vehicle corresponding path. Vehicle seat
adjust it properly? seat belts. Label is directly next belt routing paths or devices are
to the corresponding b
...