The United Nations Economic Commission for Europe (UN ECE) Regulation on the protection of occupants in the event of a frontal impact, ECE Regulation No. 94, was first published in 1995. This Regulation applies to M1 category vehicles, i.e. passenger cars and multipurpose passenger vehicles, with a GVW not exceeding 2,500 kg; it requires them to be subjected to a frontal impact into an offset deformable barrier at a speed of 56 km/h with 50th percentile male Hybrid III dummies in both the driver’s and front outboard passenger seating positions.
Although this Regulation has been amended a number of times since its original publication, the basic test procedure has remained unchanged. Therefore, in 2008, the UN ECE Working Party responsible for occupant protection, the Working Party on Passive Safety (GRSP), set up an Informal Group to review the front impact test procedure with a view to updating it and/or supplementing it with additional test procedures to improve occupant protection levels, whilst also taking into account potential future requirements on the crash compatibility between vehicles.
The Informal Group considered the latest data and research available from expert groups such as the European Enhanced Vehicle Safety Committee (EEVC) and from research projects such as Frontal Impact and Compatibility Assessment Research (FIMCAR) project, and identified a number of potential new frontal impact test scenarios. Most of the identified front impact test procedures would require considerable development before they could be implemented in an ECE Regulation. However, the group identified one test procedure that would improve overall occupant protection, but which could be implemented relatively quickly; a 50 km/h frontal impact into a full width rigid barrier.
Whilst it is generally recognised that the 56 km/h offset deformable barrier front impact test is a more severe test of the vehicle and body structure, the 50 km/h rigid barrier front impact is generally accepted as providing a more rigorous assessment of the restraint system's performance. Furthermore, as compliance with a 50 km/h rigid barrier front impact test is already specified within the legal requirements of a number of countries around the world, e.g. USA, Japan, etc., a wealth of experience and data relating to this test specification already exists. For these reasons, the Informal Group initially focussed on creating a 50 km/h rigid barrier front impact test specification, which would be introduced as a new ECE Regulation rather than as an additional test procedure for inclusion into ECE 94.
The full test specification developed by the Informal Group applies to all M1 category vehicles with a GVW not exceeding 3,500 kg and requires a 50th percentile male Hybrid III dummy to be placed in the driver's seating position and a 5th percentile female Hybrid III dummy to be placed in the front outboard passenger seating position. During the test, limits on head performance criterion (HPC), neck injury criteria, thorax compression criterion, thorax viscous criterion and femur force criterion must be met for both dummies. Additionally, requirements on steering column movement, door openability, fuel system leakage and, in the case of vehicles with electric powertrains, requirements on electrolyte spillage, isolation resistance and protection against electric shock are specified.
The draft Regulation, which has been given the title "approval of passenger cars in the event of a frontal collision with focus on the restraint system", was submitted to the World Forum for Harmonisation of Vehicle Regulations (WP.29) at its 167th session in November 2015, where it was formally adopted. It has been provisionally given the Regulation no. 137, but has not yet been allocated a provisional entry into force date. Official publication of the final version of ECE 137 is expected during June / July 2016.
An 01 series of amendments to Regulation No. 137, which introduces a more stringent limit on the thorax compression criteria for the 5th percentile female dummy seated in the front outboard passenger seat, was also adopted at the 167th session of WP.29 in November 2015. This 01 series of amendments is also expected to be officially published around June / July 2016.