Appendix ANNEX A PASSIVE SAFETY — CRASHWORTHINESS

Detailed description of the passive safety provisions covered in Section 4.1.7b of this document.

Collision is a risk of train operation that may be analysed depending on the nature of the different obstacles encountered. In the case of a railway obstacle (another train or rail vehicle), such an eventuality should normally be under the control of the railway system, signalling system, the operational rules, the automatic control mechanisms and the brakes which should be designed to reduce the probability of such an event to as close to zero as possible.

However, obstructions from outside the rail system such as road vehicles or lumps of rock may accidentally occur in the path of a train.

In the event of such a collision, an energy absorbing system allows the controlled deformation of parts specially designed for this purpose.

Improvements to rolling stock passive safety (to limit damage in the event of a collision) are not designed to compensate for any shortcomings in the active safety (collision avoidance) of the railway system but to supplement it in order to take account of events outside the railway system's control.

The guiding principles of this improvement are:

• to avoid overriding in the event of a collision between the two vehicles involved or between two vehicles behind one another in the same trainset,

• to limit the degree of deceleration in areas of the train reserved for passengers and the crew,

• to ensure minimal penetration of areas of the train reserved for passengers and the crew,

• to ensure the controlled deformation of the leading vehicle and the rest of the train by introducing elements that can absorb the energy generated by a collision elements and/or crumple zones.

Three reference accidents are considered:

Collision between two identical high speed trainsets at a relative speed of 36 km/h

Collision between a high-speed trainset and a railway vehicle equipped with side buffers at a speed of 36 km/h. The railway vehicle is a four-axle freight wagon UIC 571-2 with an 80 tonne mass.

Collision at a speed of 110 km/h at a level crossing with a 15 tonne lorry represented by a rigid mass presenting a vertical surface for impact.

• For Scenario 1 the driver's cab and the passenger saloons should not present plastic deformations which could affect the occupants' safety.

  For Scenarios 2 and 3 the driver's cab may deform but the passengers saloons should not present plastic deformations which could affect the occupants' safety. The rear of the cab shall be fitted with a rigid survival cell for the driver with a length of at least 0,75 m. Access to the staff or passenger compartment located behind the cab shall be kept free at all times. Drivers' cabs at the ends of vehicles must have at least a door or a gangway allowing easy access for staff in an emergency to a longitudinal corridor leading to the opposite end. If a door is provided, it must open outwards from the driver's cab and must be as airtight as possible.

  However, it must be possible to open the door just by pushing or in some other simple and quick manner. If there is any risk of obstruction (baggage, passengers), the door must be of the swing-type (opening outwards and inwards) or of the sliding type.

  The exit must be easily accessible, not only to the driver, but also to the second man.

  Accordingly the seat(s) must not be a major obstacle to reaching the exit.

  It must be possible to exit from the driver's cab safely and without difficulty over a distance of at least 2 m. The exit should measure at least 1 800 mm in height, at least 500 mm in width, and the free door space should measure a minimum of 1 700 mm × 430 mm.

• 6 MJ of crash energy shall be dissipated, of which at least 75 % shall be in the front part of the first vehicle of the trainset and the remainder distributed over all the intercar links down the train,

• crashworthiness shall be increased in passenger saloons located in the leading vehicle and in the driver's survival cell. These sections shall be designed with a static load limit of at least 1 500 KN above the mean crush force of the crumple zones for the three collision scenarios considered,

• the crashworthiness of the leading vehicles should be consistent with that of the other vehicles in the trainset. The forces experienced in the crumple zones should not result in mean accelerations exceeding 5g in the passenger areas in the leading vehicle or in the driver's survival cell,

• anti-climbing devices shall be fitted between the vehicles comprising the train set.