European Enhanced Vehicle-Safety Committee

WG20 Terms of Reference

Rear Impact Test Procedure(s) and the Mitigation of Neck Injury

The purpose of the EEVC Working Groups is to provide the EEVC Steering Committee with impartial advice, based upon scientific evidence, in order to support the development and enhancement of European safety standards and legislation. The specific activities of the Working Groups will be as directed by the Steering Committee from time to time. EEVC Working Group 20's general remit is to respond to EEVC Steering Committee request to develop test procedures for rear-end collisions, with a prime focus on neck injury reduction (Whiplash).

WG20 - Specific Activities
Each of the following activities shall be considered by the Working Group and a delivery plan developed. The plan shall include the resource requirement, timelines and interdependencies with other Working Groups or outside bodies. Each plan shall also contain milestones suitable for review by the regular meetings of the Steering Committee and, where appropriate, break points. Provision shall be made to ensure that any final recommendation is accompanied by an impact assessment suitable for use in the regulatory arena. The plan shall be submitted to the EEVC Steering Committee for their final approval.

1) Static Test of Head Restraint Geometry
The Working Group shall develop a static test of head restraint geometry as a first stage in the mitigation of injuries in low-speed rear impacts. The WG will validate the repeatability and reproducibility of the test procedure and test tools. A cost-benefit analysis will be undertaken, and based on this recommendations for limits on head restraint back-set and height requirements will be made.
Deliverable: A validated test procedure and cost-benefit analysis.

2) Dynamic Test of Head Restraint Geometry
The Working Group should consider the development of a dynamic test of head restraint geometry as an optional alternative to the static assessment. The Working Group shall provide advice to the Steering Committee as to whether this option should be pursued further and, if so, develop a validated test procedure for the dynamic assessment of head restraint geometry.
Deliverables
a) A recommendation to the EEVC Steering Committee as to whether the option of a dynamic test of head restraint geometry should be pursued further.
b) If so, a validated test procedure and an extension to the cost-benefit analysis of the static test procedure to cover optional dynamic testing.


3) Dynamic Injury Prediction Test Procedure
The Working Group shall develop a dynamic test procedure for rear-end collisions, with a prime focus on neck injury reduction. The procedure should be a sled-based test with a generic crash pulse, unless this can be shown to be inappropriate. The test conditions should be appropriate with regard to real world accident data, and it may be necessary to have tests at more than one severity; for instance to prevent optimisation of safety systems to a single test pulse, to test seat integrity at high severities, or to test the integrity of energy absorbing systems at high severities.
In order to ensure that neck injury risk is not reduced at the cost of an increase in other injuries (e.g. lumbar or thoracic spine, or soft tissue), due regard should be given to a holistic approach to rear impact injury risk reduction. The test procedure must address the range of vehicle properties that can influence occupant loading as a function of the vehicle crash pulse, e.g. use of the seat-belt system and the seat system with vehicle body attachment points. The procedure must include consideration of active safety systems that are triggered by crash sensor information, pre-crash sensor information or occupant interactions and position.
The Working Group will collaborate with EEVC WG12 (Biomechanics):

  • WG20 and WG12 will select the most appropriate size of dummy for the test procedure
  • WG12 will recommend the dummy for the dynamic test procedure
  • WG12 will recommend biomechanically based injury criteria and to recommend injury risk functions for those criteria
  • WG20 will supply WG12 with all the necessary input data regarding crash conditions, instrumentation and requirements and the interface between dummy and test set-up
  • WG20 will be responsible for co-ordination with WG12

Deliverable: A validated test procedure and cost-benefit analysis.

4) Contribute to GRSP
EEVC WG20 shall provide the EEVC contribution to the GRSP Global Technical Regulation Informal Working Group (IWG) on head restraints. This will be an ongoing task for the duration of the IWG on head restraints.

Approved by the EEVC Steering Committee - October 2006