The Audi A7 has standard driver and front passenger side knee airbags mounted low on the dashboard. These airbags helps prevent the driver and front passenger from sliding under their seatbelts or the main frontal airbags; this keeps them better positioned during a collision for maximum protection. Knee airbags also help keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The S90 doesn’t offer a front passenger side knee airbag.
Earlier warning of stopped traffic, traffic signals, dangerous road conditions, weather, or accidents, can keep driver's safer and prevent crashes. The A7 has Traffic Light Information, a system that seamlessly communicates important warnings to the driver about impending danger, if they're available. The S90 doesn’t offer a system that can receive automated systems from infrastructure.
Both the A7 and the S90 have standard driver and passenger frontal airbags, front and rear side-impact airbags, driver knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, all wheel drive, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, post-collision automatic braking systems, daytime running lights, lane departure warning systems, rearview cameras, available blind spot warning systems, around view monitors and rear cross-path warning.

