By Bob Cakebread
Sian Thornthwaite Consultants, Ltd.

European Commission Directives have, until the latest amendments, required seat belts (lap belts) on exposed seats in coaches and the front outboard seats in minibuses. An exposed seat being one that does not have another high backed seat in front of it.

There was growing evidence that passengers were being ejected, or partially ejected from minibuses and coaches mainly in frontal and roll-over accidents resulting in a disproportionate number of fatal injuries. Research in the United Kingdom (UK) also showed the risk of roof collapse of coaches in roll-over accidents and that the risk of passenger injury in frontal impact accidents involving minibuses was not dissimilar to that of cars.

A spate of accidents in the UK in 1993/94 put these issues back into the European spotlight - the UK being unable to enforce any legislation that went beyond the then current EC Directives.

At this point it is worth noting that vehicle regulations developed by the United Nations Economic Commission for Europe (UN/ECE) included one covering the strength of the superstructure (UN/ECE R66) and one covering energy absorbing seats (UN/ECE R80), both intended for large passenger vehicles. Although they are called regulations, they are more like standards in their optional application.

In 1993, UK legislation requiring coaches to comply with UN/ECE R66 came into effect but could not legislate for seat belts on all seats in minibuses and coaches as seat belts were already covered by EC Directives.

The European Commission proposed an amendment to the seat belt and seat belt anchorage Directives - three point belts for small vehicles, two point (lap) belts for large ones. There was much concern that coach passengers may not wear their belts and that a lap belt may cause injuries from contact with the seat in front. EC funded research to establish whether it was possible to design a seat that was strong enough to take seat belt anchorages and yet be energy absorbing (i.e. comply with UN/ECE R80) and whether or not the seat back could be designed to be compatible with a lap belted occupant in the seat behind. The outcome was positive, leading to amendment to the relevant Directives as follows:

• Three point belts on vehicles up to (7,700 lbs.) 3500 kg. with seat standards the same as those applicable to cars.

• Vehicles over 11,000 lbs. (5,000 kg.) lap belts (3 point optional) with energy absorbing seat (equivalent to UN/ECE R80) and seat back head impact performance criteria.

• Vehicles over 3500 kg. but not exceeding 5000 kg. to have the option of either of two requirements above.

The UK went further with research that has shown that it is technically feasible to design a seat that will take a three-point belt and comply with the energy absorbing seat back and head impact criteria of the latest Directives.

A new EC Directive on bus and coach construction is also in the pipeline that will include a strength of superstructure requirement and a vehicle stability test in line with current UK practice.

The United Kingdom

Accidents in the UK in 1993/94 not only drew attention in Europe but much more so in the UK - much of which focused on the safety of school transport.

While the spotlight in Europe turned to the development of new Directives that would take some years to come into effect, the UK government was under pressure to act. A review of the issue was undertaken where the possibility of a limited UK action without crossing the boundaries of EC law was established. School transport being the focus of public concern action was taken on this limited but significant sector.

Regulations were introduced in April 1996 requiring:

• A seat with a seat belt for a least the number of children carried;

• A child being aged 3-15 inclusive;

• A minimum of a lap belt;

• Applies to home to school transport, school trips and other trips where the vehicle is hired to transport children;

• Regular bus services available to the general public are exempt.

The regulations apply to vehicles when used to transport children which resulted in retro-fitting of belts in most cases.

Small vehicles i.e. minibuses (typically less than 3500 kg [7700 lbs]) were less affected by this legislation. The demand for seat belts on these vehicles was such that the major UK manufacturers fitted belts as standard on new vehicles - these being lap and diagonal belts from around 1993 onwards.

The future

Current seat and seat belt requirements have been developed on the basis of forward facing seats, however rearward facing seats perhaps can offer greater benefits although studies suggest that some people may suffer travel sickness.

To date there are no seat performance requirements for rearward facing seats, and whether or not it is feasible to develop an acceptable system for side facing seats remains to be seen.