Abstract
The passive safety is one of the most important approval subject in the legislation of vehicles. Considering - as an example - the required strength of bus superstructures in case of a rollover accident, the paper discusses generally some essential questions like: the standard accident, the acceptable survival criteria, the approval tests, and gives concrete solutions from the bus example.
An international expert group is working in Geneva on the modification of ECE Regulation 66. (Strength of bus superstructure) Therefor this paper has an up-to-dateness, too, and its presentation and discussion can help to find internationally acceptable solutions to the modification of Reg.66. The paper is based on the experiences of about twenty bus rollover tests performed in Hungary. These rollover tests represent 8 different types of test.