ISO 29061-1

ISO/DISPRF 29061-1:2025(en)
ISO/TC 22/SC 36/WG 2
Secretariat: SIS 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 1:
Vehicles and child restraint systems equipped with ISOFIX
anchorages and attachments
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 1: Véhicules et systèmes
de retenue pour enfants équipés d’ancrages et attaches ISOFIX
Partie 1: Véhicules et systèmes de retenue pour enfants équipés d'ancrages et d'attaches ISOFIX
PROOF
ISO/PRF 29061-1:2025(en)
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ii
ISO/DISPRF 29061-1:2025(en)
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 ISOFIX usability evaluation procedure and scoring principles. 5
4.1 Evaluation procedure . 5
4.2 Scoring system . 6
5 Usability evaluation forms . 6
Annex A (informative) Recommendations regarding scoring and assessment . 25
Annex B (informative) Example usability rating classes . 27
Bibliography . 28

iii
ISO/PRF 29061-1:2025(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
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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).
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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 29061-1:2010), which has been technically
revised.
The main changes compared to the previous edition 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 29061-1:2025(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 ISOFIX systems to promote improved
ISOFIX design for easy and correct use.
It provides child restraint and vehicle manufacturers with a tool for the assessment of the usability of new and
current ISOFIX 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 ISOFIX system and assists them in selecting
CRSs and vehicles with ISOFIX systems that are easier 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 29061-1:2025(en)

Road vehicles — Methods and criteria for usability evaluation of child
restraint systems and their interface with vehicle anchorage systems
— —
Part 1:
Vehicles and child restraint systems equipped with ISOFIX anchorages
and attachments
1 Scope
This document provides criteria for judgement of usability of child restraint systems (CRSs) with ISOFIX
attachments and their corresponding anchorage systems in vehicles.
This document provides criteria for a separate evaluation of the CRS ISOFIX attachments, of the ISOFIX
anchorage installation in vehicles, and an evaluation of the interface issues when installing a CRS in a certain
vehicle.
This document covers both rigid and flexible attachments of the CRS to the vehicle ISOFIX anchorages.
NOTE 1 CRS includes enhanced child restraint system (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
anchorage
part of the universal interface provided in a vehicle
Note 1 to entry: See also ISOFIX anchorages (3.9.2(3.9.2),), top tether anchorage (3.17.1(3.17.1)) and lower tether
anchorage (3.13(3.13).).
3.2 3.2
anti-rotational device
device intended to restrict forward or rearward rotation of a child restraint system (CRS) (3.6(3.6))
ISO/PRF 29061-1:2025(en)
3.2.1 3.2.1
primary anti-rotational device
device intended to restrict forward rotation of a child restraint system (CRS) (3.6(3.6))
EXAMPLE Top tether (3.17(3.17)) or support leg (3.16(3.16).).
3.2.2 3.2.2
secondary anti-rotational device
device intended to restrict rearward rotation of a rearward-facing child restraint system (CRS) (3.6(3.6))
EXAMPLE Rebound bar (3.11(3.11)) or lower tether (3.12(3.12).).
3.3 3.3
attachment
part of the universal interface provided with the child restraint system (CRS) (3.6(3.6))
Note 1 to entry: See also ISOFIX attachments (3.9.3(3.9.3).).
3.4 3.4
audible
capable of being heard in normal environmental conditions
3.5 3.5
base
part of the child restraint system (CRS) (3.6(3.6)) equipped with ISOFIX attachments (3.9.3(3.9.3)) which can
be attached to the ISOFIX anchorages (3.9.2(3.9.2)) separately from the CRS shell
Note 1 to entry: The CRS shell is attached on the CRS base in the normal use.
3.6 3.6
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.
3.7 3.7
connector
connecting and locking device to the universal interface, provided with the child restraint system (CRS)
(3.6(3.6),), and part of the attachment (3.3(3.3))
3.8 3.8
slack
looseness of an adjustable strap that is likely to affect the performance of the child restraint system (CRS)
(3.6(3.6)) adversely
3.8.1 3.8.1
hidden slack
unintended looseness of an adjustable strap that is likely to affect the performance of the child restraint system
(CRS) (3.6(3.6)) adversely, and that cannot be easily detected
ISO/DISPRF 29061-1:2025(en)
3.9 3.9
ISOFIX
system for the connection of child restraint systems (CRSs) (3.6(3.6)) to vehicles, which has two rigid
anchorages (3.1(3.1)) in a vehicle seating position located near the seat bight (3.14(3.14),), corresponding
rigid attachments (3.3(3.3)) on the CRS, and a means to limit the pitch rotation of the CRS
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.]
3.9.1 3.9.1
ISOFIX accessibility tester
device used to check the accessibility of an ISOFIX anchorage (3.9.2(3.9.2))
Note 1 to entry: The dimensions are defined in ISO 13216-1:1999, Figure 3.
3.9.2 3.9.2
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 (3.14(3.14)) or seat structure to
accept and restrain a child restraint system (CRS) (3.6(3.6)) with prescribed attachments (3.3(3.3))
Note 1 to entry: Anchorages (3.1(3.1)) may be rigid or semi-rigid according to ISO 13216-1:1999, Annex A.
3.9.3 3.9.3
ISOFIX attachment
one of two (2) prescribed connections, in accordance with ISO 13216-1:1999, extending from the child
restraint system (CRS) (3.6(3.6)) structure, and compatible with an anchorage (3.1(3.1))
Note 1 to entry: Attachments (3.3(3.3)) may be rigid or non-rigid (flexible) according to ISO 13216-1:1999, Annex B.
3.10 3.10
pictogram
illustration or photo used to represent a concept or an operation
Note 1 to entry: A pictogram can be supplemented by text.
3.11 3.11
rebound bar
type of anti-rotational device (3.2(3.2)) intended to restrict the rearward rotation of a rearward-facing child
restraint system (CRS) (3.6(3.6))
Note 1 to entry: It usually comprises a rigid device that, when in its operational position, rests against the vehicle
seatback.
3.12 3.12
lower tether
type of anti-rotational device (3.2(3.2)) intended to restrict the rearward rotation of a rearward-facing child
restraint system (CRS) (3.6(3.6))
Note 1 to entry: It usually comprises a tether strap or other hardware attached near the back or base (3.5(3.5)) of the CRS
that connects to a lower tether anchorage (3.13(3.13).). It incorporates a device to enable it to be connected to such an
anchorage (3.1(3.1).).
ISO/PRF 29061-1:2025(en)
3.13 3.13
lower tether anchorage
anchorage (3.1(3.1)) on the vehicle seat track or on or close to the vehicle floor to which a lower tether
(3.12(3.12)) can be attached
[SOURCE: ISO 13216-4:2020, 3.1]
3.14 3.14
seat bight
area close to the intersection of the surfaces of the vehicle seat cushion and the seat back
[SOURCE: ISO 13216-1:1999, 3.8, modified — "“or squab"” was deleted from the end of the definition.]
3.15 3.15
single action
operation that can be completed without the need to undertake a secondary action
EXAMPLE This includes tightening a strap by pulling it without the need to release a locking system; or attaching to
an anchorage (3.1(3.1)) without the need to depress the seat cushion.
3.16 3.16
support leg
type of anti-rotational device (3.2(3.2)) comprising a permanent attachment (3.3(3.3)) to a child restraint
system (CRS) (3.6(3.6),), or a base (3.5(3.5)) of a CRS, 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.
3.17 3.17
top tether
tether strap (or equivalent) attached at or near the top of a child restraint system (CRS) (3.6(3.6),),
incorporating a device to enable it to be connected to a top tether anchorage (3.17.1(3.17.1))
3.17.1 3.17.1
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 (3.17(3.17)) can be attached
3.17.2 3.17.2
top tether strap
webbing strap which extends from the top of a child restraint system (CRS) (3.6(3.6)) to the top tether
anchorage (3.17.1(3.17.1)) and which is equipped with an adjustment device, a tension-relieving device and
a top tether (3.17(3.17) )connector (3.7(3.7))
[SOURCE: ISO 13216-2:2004, 3.3]
3.18 3.18
usability
extent to which a vehicle or child restraint system (CRS) (3.6(3.6)) is capable of being used and is convenient
and practical in use (separately or combined)
3.19 3.19
visible
capable of being seen without tools (other than spectacles) in normal environmental conditions
ISO/DISPRF 29061-1:2025(en)
3.20 3.20
harness
child restraint system (CRS) (3.6(3.6)) belt assembly comprising shoulder restraints, a crotch strap and
optionally lap straps
4 ISOFIX usability evaluation procedure and scoring principles
4.1 Evaluation procedure
This document provides a procedure to evaluate the usability of ISOFIX attachments on CRSs, ISOFIX hardware
in vehicle seating positions, and the interface between ISOFIX systems for specific combinations of CRSs and
vehicle seating positions. The evaluation takes into consideration CRSs that are equipped with either flexible
or rigid ISOFIX attachments including those that include a top tether or other anti-rotation device(s). The
usability protocol is intended to be objective and repeatable.
The evaluation is most easily accomplished using a team of two people having basic knowledge of CRSs and
being familiar with the technical terms used. However, they should preferably be unfamiliar with the CRS
model to be evaluated.
The procedure for all three aspects of the process: the CRS, the vehicle seating position and the resulting
interface, takes about 45 min.
The necessary materials include:
— — the usability evaluation form (in either paper or electronic format),);
— — the vehicle owner’s instruction manual,;
— — the CRS instruction manual, including instruction video if applicable,; and
— — a screwdriver, or a simple prying/turning tool.
A copy of the terms and definitions from this document can also be helpful.
For the independent assessment of CRS ISOFIX connector function, the use of an ISOFIX bar dummy is
recommended. In its simplest form this can be a straight 6 mm bar of at least 280 mm length, it can consist of
two aligned ISOFIX anchorages connected to a rigid supporting material, or a demo seat equipped with ISOFIX
anchorages.
For the independent assessment of vehicle ISOFIX anchorages and the available space around them, the use
of an ISOFIX accessibility tester, or a standard ISOFIX connector is recommended, fulfilling the requirements
of ISO 13216-1:1999, Figure 3.
Initially, the CRS shall be in the condition as supplied to the consumer. The evaluation process includes all the
steps necessary, including assembly, to complete the installation.
Unpacking the CRS, removing the box, 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 CRS (i.e. forward-facing/rearward-facing, upright/reclined, with base/without base)
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, followed by the ease of installation and
removal of the CRS.
ISO/PRF 29061-1:2025(en)
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 and usage of the restraint and vehicle. 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: ISOFIX child restraint system;
— — Form 2: Vehicle ISOFIX and top tether anchorages;
— — Form 3: Interface — Installing the CRS, or base with seat, in the vehicle.
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/-1/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 29061-1:2025(en)
Form 1: ISOFIX child restraint system
For the independent assessment of CRS ISOFIX connector function, the use of an ISOFIX bar dummy is recommended (see 4.14.1).).
Date of evaluation  Evaluated by   Test no.

☐ Rigid attachments ☐ Flexible attachments ☐ Top tether ☐ Support leg ☐ Secondary anti-rotational device
Child restraint ISOFIX system
Manufacturer
a a
Child seat make/brand and model   Base make/brand and model model
Country/region of use   Country/region of use
b b
Certification/type approval no.   Certification/type approval no.
Production no. (serial no./SAI no., etc.)   Production no. (serial no./SAI no., etc.)
Date of manufacturing (yyyy-mm-dd)   Date of manufacturing (yyyy-mm-dd)
☐ Forward-facing ☐ Rearward-facing
Mode tested
Type (infant, group 0, integral, A2, etc.)   CRS inclination tested ☐ Upright/normal ☐ Reclined

Appropriate child size range for this
mode according to instruction
manual Mass range (kg):  Height range (cm): Age range (months or years):
a If applicable.
b Where applicable.
ISO/DIS 29061-1:2025(en)
a
Form 1.1: CRS ISOFIX instructions and labels
N/
Good Average Poor Importance Notes
A
Do CRS or base Visually obvious, able to Pictures plus written Only written
instructions clearly show use with pictures only. instructions provided. instructions provided or
how to prepare and Labels on CRS self- Labels on CRS non self- non self-explanatory
use/attach the ISOFIX explanatory, or not explanatory, or viewable pictures, or nothing
1.1.1
attachments? necessary. from one direction only. shown.
Labels on CRS ☐ ☐ ☐ A ☐
Instruc
...