DEKRA accident research division has carried out indepth analyses of 371 accidents involving 395 buses which occurred from 1985 to 1997 in Germany. From these, pointers were derived toward possible improvements in the active safety and, in conjunction with crash test results, in the passive safety of buses.

With regard to the pre-crash phase of the accidents, findings emerge on, among other things, the relative significance and frequency of the following characteristics:​ speed being driven before collision, critical situation triggering the accident (accident type), consequences of bus occupants and opposites. From these findings, potential benefits of technical aids and bus equipment can be assessed.

A main focus of actual accidento ccurrencesin volving buses concerns in which buses topple over their side. On this point, relevant characteristics resulting from the accident assessmentsa re also described. The results of actual accident simulations carried out at the DEKRA crash centre involving the overturning of a moving bus onto its side complete this topic.

From the collision parameters (kind of opposite, driving and collision velocity etc.) pointers emerge regarding the performance of appropriate crash tests for the analysis of internal bus safety. In this context there is also a discussion of the results of bus crash tests carried out at the DEKR4 crash centre (vehicle damage, seat- and passenger-stresses).

Lastly, using actual accident occurrences, there is a discussion of external bus safety. A description of the relevant characteristics of collisions with other traffic participants (trucks, buses, cars, two-wheeled vehicles, pedestrians) provides pointers to potential improvements