The passenger compartment of the RZ remained stable in the frontal offset test. Dummy numbers showed good protection of the knees and femurs of both the driver and passenger. Lexus showed that a similar level of protection would be provided to occupants of different sizes and to those sitting in different positions.  Protection of all critical body areas was good for the front passenger.  Analysis of the deceleration of the impact trolley during the test, and analysis of the deformable barrier after the test, revealed that the RZ would be a moderately benign impact partner in a frontal collision. In the full-width rigid barrier test, chest protection was rated as weak for the rear passenger, based on dummy readings of compression.  Otherwise, protection of both dummies was good or adequate in this test. In the side barrier test, protection of all critical body areas was good and the car scored maximum points. However, in the side pole impact, dummy readings of rib compression indicated a marginal level of protection.  Control of excursion (the extent to which a body is thrown to the other side of the vehicle when it is hit from the far side) was found to be good. The RZ has a counter-measure to mitigate against occupant to occupant injuries in such impacts and this performed well in Euro NCAP's test. The centre airbag is mounted on the driver's seat but provides protection to both front seat occupants in a side impact.  Tests on the front seats and head restraints demonstrated good protection against whiplash injuries in the event of a rear-end collision.  A geometric analysis of the rear seats also indicated good whiplash protection.   The RZ has an advanced eCall system which alerts the emergency services in the event of a crash.   The car also has a system which applies the brakes after an impact, to avoid secondary collisions.  Lexus demonstrated that, if the car entered water, the doors and windows of the RZ would remain functional long enough to allow the occupants to escape.

In both the frontal offset and side barrier tests, good protection was provided to all critical body areas for both child dummies, and the Lexus RZ scored maximum points in this part of the assessment.  The front passenger airbag can be disabled to allow a rearward-facing child restraint to be used in that seating position.  Clear information is provided to the driver regarding the status of the airbag and the system was rewarded.  The vehicle is equipped with an indirect child presence detection system, which warns when a child or infant may have been left in the car.   All of the child restraint types for which the RZ is designed could be properly installed and accommodated in the car. 

Protection of the head of a struck pedestrian or cyclist was predominantly good or adequate, with poor results recorded only on the stiff windscreen pillars.  Protection of the pelvis was good at all test locations and that of the femur was at least adequate.  However, protection of the knee and tibia was poor towards the centreline of the car.  The autonomous emergency braking (AEB) system of the Lexus can respond to vulnerable road users as well as to other vehicles.  The system performed well in tests of its response to pedestrians and full points were scored in tests of the system’s reaction to cyclists, including dooring, in which the car prevents or warns against door opening if a cyclist is approaching from behind.  Similarly, the AEB system performed well in all tests of its response to motorcyclists and scored full points.

The autonomous emergency braking (AEB) system of the Lexus RZ performed well in tests of its reaction to other vehicles, including the head-on scenarios.  A seatbelt reminder system is fitted as standard to the front and rear seats and the car is equipped with a system to detect driver fatigue, such as drowsiness and long distraction, where the driver is not focussed on the driving task.  The system does not recognise short distraction or phone use.  The lane support system gently corrects the vehicle’s path if it is drifting out of lane and also intervenes in some more critical situations.  The speed assistance system identifies the local speed limit, and the driver can choose to allow the limiter to be set automatically by the system.