UN R129 Base text (05 series) · UNECE Regulation No. 129 (ECE R129) — Uniform provisions concerning the approval of Enhanced Child Restraint Systems used on board of motor vehicles (ECRS).
UN R129 — 05 series of amendments
Changes from 04 series of amendments (supplement 5)
- What changed
- Annex 18, Table 1 has new shoulder height values for statures from 40 cm to 70 cm.
- A new note to Table 1 says that the minimum shoulder height dimension for statures below 40 cm must be determined by extrapolation.
- Paragraph 6.2.1.1. now allows a separate insert layer for small babies with a stature < 50 cm, if only one layer is used for each range.
- Why
- The text was prepared to improve the shoulder height requirements to properly take the dimensions of premature newborns into account.
- The Justification says that the shoulder height from ≤ 40 cm until 75 cm does not correspond with real-life anthropometrical data of children.
Q1What changed31 changes
Shoulder heights for statures from 40 cm to 70 cm (Annex 18, Table 1)
Annex 18, Table 1 has new shoulder height values in the rows for statures from 40 cm to 70 cm. For example, for a stature of 45 cm, the shoulder height values change from 27.4 and 29.0 to 17.6 and 23.5. The row for ≤40 is now marked 40*. A new table note says that the minimum shoulder height dimension for statures below 40 cm must be determined by extrapolation. The note also says that there must be no minimum stature dimension declared < 35 cm.
Insert layer for small babies (para. 6.2.1.1.)
Paragraph 6.2.1.1. still says that inserts must form only one layer on the seat surface. To give protection for small babies with a stature < 50 cm, a separate insert layer may now be made available. The condition is that only one layer is used for each range. Additional ‘comfort’ inserts are permitted for any stature, provided they are not needed to comply with the requirements of the regulation. Before, the paragraph said that the one-layer rule did not preclude the use of additional ‘comfort’ inserts, with the same condition.
Transitional provisions for the 05 series (paras. 16.17. to 16.17.4.)
New paragraph 16.17. gives the transitional provisions applicable to the 05 series of amendments. From the official date of entry into force, no Contracting Party applying this Regulation may refuse to grant or accept 05 series UN type-approvals. As from 1 September 2028, Contracting Parties are not obliged to accept UN type-approvals to the preceding series first issued after 1 September 2028. As from 1 September 2029, they are not obliged to accept type-approvals issued to the preceding series of amendments. They must continue to accept, and grant extensions to, these approvals for Enhanced Child Restraint Systems not affected by the 05 series changes (paragraph 16.17.4.).
Approval mark examples (Annex 2)
In the examples of Annex 2, the approval number is now 052439, instead of 042439 or 042450. The explanatory texts now refer to the 05 series of amendments instead of the 04 series of amendments.
Q2Why it changed
- Proposed by
- Expert from the Kingdom of the Netherlands
- Working party
- GRSP, 78th session (December 2025)
Reasons
After discharge from hospital, premature newborns are frequently transported home by car. The distance between the seat bottom and the lowest shoulder harness outlet is often too large, so the ECRS provides only an inappropriate fit. There is a need for type-approved ECRSs starting from 40 cm with a proper harness fit.
Sources (3)
“After discharge from hospital, premature newborns are frequently transported home by car and need a safe child restraint system.”
“The distance between the seat bottom and the lowest shoulder harness outlet is often too large and the ECRS thus provides only an inappropriate fit.”
“There is a need for type-approved ECRSs starting from 40 cm with a proper harness fit.”
The shoulder height from ≤ 40 cm until 75 cm does not correspond with real-life anthropometrical data of children. The updated shoulder height data are based upon NHS Anthropometry data.
Sources (2)
“The shoulder height from ≤ 40 cm until 75 cm does not correspond with real-life anthropometrical data of children.”
“The updated shoulder height data are based upon NHS Anthropometry data (see Schleuning et al: 2022).”
Paragraph 6.2.1.1. is changed to allow an insert layer for premature infants, so that ECRS manufacturers are able to comply with the requirements.
Source
“Paragraph 6.2.1.1. is modified to allow for one additional insert layer in order for ECRS manufacturers to be able to comply with the requirements, for premature infants”
The value for statures below 40 cm is changed, so that manufacturers do not declare such statures without properly addressing their shoulder heights. For that purpose, the shoulder heights below 40 cm may be extrapolated, rather than taking the value at 40 cm as in the original provisions.
Sources (2)
“In Annex 18 table 1, the value for statures below 40 cm has been modified, in order to make sure that manufacturers do not declare statures below 40 cm, without properly addressing their corresponding shoulder heights.”
“For that purpose, the shoulder heights below 40 cm may be extrapolated rather than taking the value at 40 cm, as was the case with the original provisions.”
Proposer's reason (informal document GRSP-78-47-Rev.1)
A minimum of 35 cm was added to prevent manufacturers from starting to declare unrealistic low statures.
Submitted by Expert from the Kingdom of the Netherlands. Working party adoption: ECE/TRANS/WP.29/GRSP/78, para. 34.
Source
“In order to prevent manufacturers to start declaring unrealistic low statures, a minimum of 35 cm was added.”
Document trail
- —ProposalGRSP-77-35Informal proposal by the Kingdom of the Netherlands that the working document is based on
- 2025-09ProposalECE/TRANS/WP.29/GRSP/2025/32Proposal by the expert from the Kingdom of the Netherlands
- —Amended in sessionGRSP-78-47-Rev.1Modifications to ECE/TRANS/WP.29/GRSP/2025/32
- —Working party adoptsECE/TRANS/WP.29/GRSP/78Session report, para. 34 (text in Annex VI)
- 2026-03Sent to WP.29ECE/TRANS/WP.29/2026/55Text that GRSP sent to WP.29 and AC.1
- 2026-06-24WP.29 adoptsECE/TRANS/WP.29/1192Adopted at the 199th session (session report, para. 103)
- PendingIn forceDate not yet known
Q3Who is affected
Vehicle manufacturer
- Check your ECRS against the new shoulder height values in Annex 18 for statures from 40 cm to 70 cm.
- If you declare statures below 40 cm, make sure their minimum shoulder height is determined by extrapolation.
- Make sure that no minimum stature dimension below 35 cm is declared for your ECRS.
- If you offer a separate insert layer for small babies (stature < 50 cm), use only one layer for each range.
- Check your approvals to the preceding series of amendments against paragraphs 16.17.2. to 16.17.4.
Component supplier
- No direct action for this role.
Technical service / Approval authority
- Use the new Annex 18 shoulder height values to check ECRS for statures from 40 cm to 70 cm.
- Check that no minimum stature dimension below 35 cm is declared.
- Be ready for requests for UN type-approvals to the 05 series of amendments (paragraph 16.17.1.).
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ⓘ This report gives advice only. It is not legal or type-approval advice.
More UN R129 change reports
- 05 series — Supplement 1
- 04 series — Supplement 6
- 04 series — Supplement 5
- 04 series — Supplement 4
- 04 series — Supplement 3
- 04 series — Supplement 2
- 04 series — Supplement 1
- 04 series — Base text
- 03 series — Supplement 12
- 03 series — Supplement 11
- 03 series — Supplement 10
- 03 series — Supplement 9
- 03 series — Supplement 8
- 03 series — Supplement 7
- 03 series — Supplement 6
- 03 series — Supplement 5