This SAE Recommended Practice is intended to establish guidelines for conducting passenger car roll-over tests so that data obtained by various test facilities may be more readily compared. A description is provided of the facilities and procedures for a curved rail-ramp technique, which has been found to be successful in producing roll-overs. Techniques and instrumentation for the study and evaluation of vehicle structure effects and occupant movement resulting from roll-overs produced by the curved rail-ramp system are also specified.

The curved rail-ramp procedure has been evolved from laboratory and field studies and tests which have sought to establish procedures which would provide realistic simulations of roll-over accidents without collision, and which would be reproducible among laboratories and between different types of passenger cars. The original issue of SAE J857 described ground level and hill roll-over techniques. However, it was found that these procedures were not always successful in producing roll-overs and the results were never reproducible. Study of the deficiencies of the previous techniques led to the addition of a curved guide rail to the ramp method of ground level roll-over, described in the original version of J857. While reproducibility of results is still limited, the curved rail-ramp system has been found to achieve roll-overs consistently, a significant step forward in the study of the roll-over event.

Because there remains some general interest in the ground level and hill roll-over techniques reported originally and for historical continuity, these techniques are reported in the Appendix to this recommended practice.

Procedures and equipment described will be subject to continuing review and will be revised as experience and improvements in the technology warrant.