Buses and coaches

Transport by bus and coach is the safest mode of road travel. However every year, around 20,000 European buses and coaches are involved in crashes causing injury or death producing 30,000 casualties, 150 of whom die. As identified by the major European ECBOS project [113] vehicle safety design can address a range of identifiable problems. Currently, the vehicle safety performance of buses is regulated by seven ECE (Economic Commission for Europe) regulations and 5 corresponding EC directives. Various research-based improvements have been identified within ECBOS to inform current policymaking, particularly crash protection measures.

Crash avoidance

Digital tachographs

Driving fatigue has been identified as a special problem for commercial transport, given the long distances which need to be covered and irregular shift patterns which affect sleep. Research indicates that fatigue is most prevalent in long distance lorry driving [112] and a factor in 20-30% of commercial road transport crashes in Europe and the United States [42] [27]. The Commission has moved to strengthen driving and working time rules and enforcement in recent years.

Council Regulation (EC) 2135/98, which amends Regulation (EEC) 3821/85, introduces a new generation of fully digital tachographs. The digital tachograph is a more secure and accurate recording and storage device than the present equipment. The new device will record all the vehicle’s activities, for example distance, speed and driving times and rest periods of the driver. The system will include a printer, for use in road side inspections and the driver will be given a card incorporating a microchip, which he must insert into the tachograph when he takes control of the vehicle. This personal driver card will ensure that inspections remain simple. The technical specifications for the digital tachograph have been laid down in Commission Regulation (EC) 1360/2002, to be mandatorily fitted in new vehicles from August 2004 European Commission overview.

Crash protection

Crash analysis shows that the occupants in the first row (driver, guide) can be ejected through the front window, or affected by the intrusion. Coupled to the seat, restraints can control better the occupant movement during a crash such that the driver remains conscious, allows driver control of the vehicle until it comes to rest and to facilitate evacuation. While the use of seat belts prevents ejection and reduces the risk of severe injury, there remains the problem of the energy absorbing capacity of the frontal area and intruding objects through the windscreen.

Frontal crash protection

In depth research shows that special protection devices need to be designed for the driver protection in the front of the coach since driver safety is not adequately considered in current regulations. Research is needed to define the requirements for front structures, a suitable test for buses and to modify the actual designs to preserve the integrity of drivers in frontal of front-lateral impacts [113].

Restraint systems

Analysis of real world crashes shows that the partial or total ejection is a mechanism for severe injury. The injury severity of the casualties is less if the bus is equipped with a seat restraint system and with laminated glasses. A side airbag especially developed for rollover movement could also prevent occupant ejection. Research has also shown that seats and their anchorages are often unable to resist the forces to which they are exposed in large coach crashes [113]. The risk of being injured by failing seat and anchorages can be reduced by integrated systems and improved standards to control the strength of seats and their anchorages.

Rollover protection

In cases of rollover where the side windows get broken, the risk of passenger ejection and injury increases. The most common body regions injured in a rollover, when no ejection occurs, are the head, the neck and the shoulder. Crash analysis indicated that injury in rollover crashes can be caused by the impact of the occupants on the side panel, on the luggage rack and also by the effects of occupant interaction. The development of new test dummies and rollover tests have been proposed [113].

Evacuation

Crash injury research shows that in serious crashes bus passengers are hindered from using the emergency doors either because they are severely injured or the doors are locked due to the impact.

ECE-Regulation 107 currently sets out the technical rules with respect to emergency doors. An effective measure would be a side window which, even broken, would remain in position and would act as a safety net keeping passengers in the bus interior. At the same time the design of coach corridors should enable rapid evacuation of bus occupants. This would require the possibility of ejecting windows easily after the coach comes to rest by pyrotechnic charges [84].

Safety of wheelchair users in coaches

A study assessing the safety of wheelchair users in coaches in comparison with travellers seated in conventional seats (fitted with headrests) has made various suggestions for modifications [108]. The work found that the heads and necks of wheelchair users were particularly vulnerable but that this could be addressed through the use of a head and back restraint. However, such a restraint should meet the requirements of ECE Regulation 17 for strength and energy absorption and the wheelchair should fit well up against the head and back restraint for maximum benefit. Further recommendations from the work were that an upper anchorage location for diagonal restraints is preferable to a floor mounted location and that the restraint anchorages should meet more rigorous strength requirements than are required at present. A protected space envelope for forward facing wheelchair passengers is also recommended. Under normal transit conditions a vertical stanchion is preferable to a horizontal bar in terms of preventing excessive movement of the wheelchair.