The agenda includes installation of belted child restraint systems and seat belt minimum length, amendment to UN R107 per document STCBC-TF173-07-02, amendment to UN R173 per document STCBC-TF173-06-05, and amendment to UN R145 per document STCBC-TF173-07-03.

UN R145 and UN R173 establish optional ISOFIX installation for vehicles of category M₂ and M₃. ISOFIX seating positions require compatibility with specific Child Restraint Fixture volumes and lower isofix forward strength of 8kN. I-Size seating positions require minimum 440mm distance between adjacent positions, compatibility with ISO/F2X and ISO/R2, and additional support leg strength testing. The document proposes allowing labels on bus windows and removing marking requirements for M₂ and M₃ from UN R145.

Proposal to modify definitions 2.9 “ISOFIX position” and 2.24 “i-Size seating position”. The revised definition of ISOFIX position specifies which types of ISOFIX child restraint systems as defined in UN R44 and UN R129 may be installed. The definition of i-Size seating position clarifies that such positions are designed to accommodate i-Size child restraint systems as defined in UN R129. The modification bases these definitions on strength test requirements rather than child restraint system category.

ISOFIX position means a position satisfying regulation requirements to allow installation of ISOFIX child restraint systems as defined in UN R44 and UN R129. i-Size seating position means a seating position satisfying regulation requirements to allow installation of i-Size child restraint systems as defined in UN R129.

The document addresses how to define and measure effective seat belt webbing length for buses of category M₂/M₃. It proposes defining effective length by pulling the lap belt at the geometrical midpoint under a 60-degree angle to form an equilateral triangle, where the leg on the buckle side defines 50 percent of pursued effective length for 2-point belts and 25 percent for 3-point belts. Additional webbing for attachment, handling, connection to spool, and spool length must be added based on seat design and geometry. The proposal suggests the definition may work using diagonal belt alone in the ghost position and questions where to include it in UN R173.

Proposed pictograms for CRS installation under UN R107 specify the following dimensions: ISOFIX pictograms with diameter 65 mm, i-Size pictograms with lateral size 65 mm, and RWF CRS in RWF adult seats pictograms with diameter 65 mm.

Initial working draft text to amend UN R107 by inserting a new definition 2.49 for Child Restraint System and adding paragraph 7.7.8.7 to Annex 3 establishing requirements for Child Restraint Systems in vehicles of category M₂ and M₃. Requirements include fitting pictograms to ISOFIX-seating positions meeting UN R145 and UN R173, fitting pictograms to i-Size-seating positions meeting those same regulations, and prohibiting rearward-facing CRS in rearward-facing passenger seats with appropriate pictograms. Three new pictograms are added to Annex 4.

The agenda includes installation of belted child restraint systems, including seat belt minimum length feedback and definition of minimum effective belt length, installation of ISOFIX child restraint systems, amendments to UN R107, ISO pictogram wording revision and dimensions, clarification of the table for M₁ vehicles, introduction of seat belt length requirements for belted child restraint systems on M₂ and M₃ vehicles, amendments to UN R145, ISOFIX force reduction, and proposals to improve ISOFIX definitions across UN Regulations.