UN R129 Supplement 4 (04 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 — Supplement 4 to the 04 series of amendments
Supplement 3 → 4
- What changed
- Paragraph 2.57. now lists a new use of a module, “as a stand-alone booster seat”, and deletes “Universal” from “stand-alone Integral Universal Belted”.
- This supplement deletes paragraph 5.5., which did not allow a Unique Identifier (UI) to replace the approval mark prescribed in paragraph 5.4.
- Paragraphs 5.6. to 5.8. become paragraphs 5.5. to 5.7.
- Why
- The proposal says that the definition of module was quite restrictive. It only allowed integral modules to be approved, and only those of a universal type.
- The proposal opens the possibility to approve an ECRS with a module that is, or can be, converted into a booster seat.
- After AC.1 amended Schedule 5 of the 1958 Agreement in March 2025, the IWG IWVTA prepared amendments to delete the UI descriptions.
Q1What changed5 changes
Definition of “Module” (para. 2.57.)
Paragraph 2.57. now lists a new use of a module: “as a stand-alone booster seat”. Before, the definition said “as a stand-alone Integral Universal Belted to restrain a child in a vehicle” and did not name a booster seat. The word “Universal” is now deleted from this use. The definition now says “one or more bases” instead of “one or more base”. It also says that a module “hosts the child” instead of “hosts and restrains the child”.
Unique Identifier (UI) paragraph deleted and paragraphs renumbered (paras. 5.5. to 5.7.)
This supplement deletes former paragraph 5.5. That paragraph said that the approval mark prescribed in paragraph 5.4. may not be replaced by a Unique Identifier (UI). This is the UI as referred to in Schedule 5 of the 1958 Agreement. Former paragraphs 5.6. to 5.8. become paragraphs 5.5. to 5.7. The text of new paragraph 5.7. begins with “The labels referred to in paragraph 5.6. above”. New paragraph 5.6. says that the particulars referred to in paragraph 5.4. may be affixed by means of a label or by direct marking.
Q2Why it changed
- Proposed by
- Expert from the Kingdom of the Netherlands (for the UI deletion, on behalf of the IWVTA IWG)
- Working party
- GRSP, 77th session (May 2025)
Reasons
The current definition of module was quite restrictive. It only allowed integral modules to be approved, and only those of a universal type.
Source
“The current definition of module is quite restrictive, only allowing integral modules to be approved and only those of a universal type.”
The proposal opens the possibility to approve an ECRS with a module that is, or can be, converted into a booster seat. It also opens the possibility to approve an ECRS with a module of a vehicle-specific application. It would allow more combinations of applications to be approved within one type of ECRS.
Sources (2)
“This proposal opens the possibility to approve an Enhanced Child Restraint System (ECRS) with a module that is, or can be, converted into a booster seat or an ECRS with a module of a vehicle-specific application.”
“This proposal would allow more combinations of applications to be approved within one type of ECRS.”
AC.1 adopted an amendment to Schedule 5 of the 1958 Agreement in March 2025. After this, the IWG IWVTA prepared amendments to delete the Unique Identifier (UI) descriptions from UN Regulation No. 129 and other UN Regulations.
Sources (2)
“following the adoption by AC.1 of an amendment to Schedule 5 of the 1958 Agreement during its March 2025 session, IWG IWVTA had prepared amendments to delete the Unique Identifier (UI) descriptions from UN Regulations Nos. 16”
“and 129 (informal documents GRSP-77-09, GRSP-77-10, GRSP-77-11 and GRSP-77-12)”
Proposer's reason (informal document GRSP-77-12)
The proposal says that ECE/TRANS/WP.29/2025/17 puts the implementation of the UI marking on hold by amending Schedule 5 of the 1958 Agreement. As the UI concept was not yet implemented in the UNECE secure internet database ‘DETA’, UI markings could not have been applied yet. A supplement was therefore considered appropriate.
Submitted by The Kingdom of the Netherlands. Working party adoption: ECE/TRANS/WP.29/GRSP/77, para. 26.
Sources (2)
“That proposal puts the implementation of the Unique Identifier (UI) marking on hold by amending Schedule 5 of the 1958 Agreement accordingly.”
“As the UI concept was not yet implemented into the UNECE secure internet database ‘DETA’, UI markings could also not have been applied yet. A Supplement is therefore considered appropriate.”
Proposer's reason (informal document GRSP-77-12)
The proposal says that the reference in paragraph 5.8. does not need to be renumbered, as it is currently incorrect. With the deletion of paragraph 5.5., it will refer again to the correct paragraph number.
Submitted by The Kingdom of the Netherlands. Working party adoption: ECE/TRANS/WP.29/GRSP/77, para. 26.
Source
“The reference in paragraph 5.8. does not need to be renumbered as this is currently incorrect and will now, with the deletion of paragraph 5.5. refer again to the correct paragraph number”
Document trail
- —ProposalGRSP-76-19Module proposal by the expert from the Netherlands, on which ECE/TRANS/WP.29/GRSP/2025/4 is based
- 2025-02ProposalECE/TRANS/WP.29/GRSP/2025/4Module proposal by the expert from the Kingdom of the Netherlands
- —ProposalGRSP-77-12UI deletion proposal by the expert from The Netherlands on behalf of the IWVTA IWG
- —Working party adoptsECE/TRANS/WP.29/GRSP/77GRSP session report, para. 26
- 2025-08Sent to WP.29ECE/TRANS/WP.29/2025/129Text that GRSP sent to WP.29 and AC.1
- 2025-11WP.29 adoptsECE/TRANS/WP.29/1188Adopted at the 197th session (session report, para. 110)
- 2026-06-04In forceC.N.225.2026.TREATIES-XI.B.16.129UN depositary notification
Q3Who is affected
Vehicle manufacturer
- No direct action for this role.
Component supplier
- Review your ECRS module designs against the new wording of the “Module” definition in paragraph 2.57.
- Update your documents that quote paragraphs 5.6. to 5.8. to the new numbers 5.5. to 5.7.
Technical service / Approval authority
- Use the new paragraph 2.57. wording of “Module” when you assess Enhanced Child Restraint Systems with a module.
- Update your checklists to the new paragraph numbers 5.5. to 5.7.
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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
- 05 series — Base text
- 04 series — Supplement 6
- 04 series — Supplement 5
- 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