Strength of student seat and their anchorages of special school bus
1 Scope
This document specifies the requirements and test methods for strength of student seat and their anchorages of special school bus.
This document applies to student seats on special school buses and anchorages used to mount the seats, as well as to restraining barriers mounted in front of these student seats.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB 14166 Safety-belts, restraint systems, child restraint systems and ISOFIX child restraint systems for occupants of power-driven vehicles
GB 24407 The safety technique specifications of special school buses
ISO 6487: 2015 Road vehicles - Measurement techniques in impact tests - Instrumentation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB 24407 and the following apply.
3.1
student seat
seat intended for preschool children over 3 years old or students in compulsory education phase on special buses
Note: according to the applicable occupants, student seats are divided into infants’ seats, primary school students' seats and primary and secondary school students' seats.
3.2
adjustment system
device by which the seat or its parts can be adjusted to a position suited to the morphology of the seated occupant
[Source: GB/T 13057-2023, 3.2]
3.3
displacement system
device by which the seat or one of its parts can be displaced laterally or longitudinally, without a fixed intermediate position, to permit easy access of the occupants
[Source: GB 13057-2023, 3.3]
3.4
locking system
device ensuring that the seat and its parts are maintained in the position of use
[Source: GB/T 13057-2023, 3.4]
3.5
anchorage
vehicle body part for anchoring a seat, including parts such as bolts for mounting the seat to the body
[Source: GB/T 13057-2023, 3.5]
3.6
seat attachment
part of the seat used for connection with the vehicle body
Note: such as chair legs and side hanging.
[Source: GB/T 13057-2023, 3.6]
3.7
seat spacing
If the seat is in the design position, the distance in the vehicle forward direction between the vertical front raised portion of the seat back of the rear seat and the vertical rear raised portion of the seat back (or restraining barrier) of the front seat is measured horizontally at a height of 200 mm above the highest point of the upper surface of the seat cushion of the rear seat.
[Source: GB 13057-2023, 3.11, modified]
3.8
restraining barrier
device which is mounted on the body structure and used to restrain or protect passengers immediately behind it during a collision or emergency braking [Source: GB/T 13057-2023, 3.12]
3.9
G point
intersection point of the vertical line tangent to the backrest surface and the upper surface of the seat cushion on the center plane of the seat in case that the seat is in the design position; intersection point of the extension line of the backrest surface and the upper surface of the seat cushion for semi-backrest seats
[Source: GB/T 13053-2008, 3.4.14, modified]
4 Requirements
4.1 Seat requirements
4.1.1 Principle
All student seats shall be mounted forward facing. Each adjustment system and displacement system provided shall be equipped with an automatic locking system, which shall remain locked after the test even though deformation and partial breakage are allowed on the adjustment system, displacement system and locking system. If a headrest is mounted, it shall not be completely disengaged from the seat during the test assessing the performance requirements of 4.1.2 and 4.1.3.
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Requirements
4.1 Seat requirements
4.2 Requirements for seat cushion
4.3 Requirements for anchorages
5 Test methods
5.1 Frontal impact dynamic test
5.2 Rear impact dynamic test
6 Judgment on the same type
7 Implementation of this standard
Annex A (Normative) Determination of injury criterion
Annex B (Normative) Measurement system and data processing
Bibliography
