Both the Ioniq 9 and CX-90 have child safety locks to prevent children from opening the rear doors. The Ioniq 9 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The CX-90’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
The Ioniq 9 has a standard front seat center airbag, which deploys between the driver and front passenger, protecting them from injuries caused by striking each other in serious side impacts. The CX-90 doesn’t offer front seat center airbags.
The Hyundai Ioniq 9 comes with a standard Surround View Monitor, while the Mazda CX-90 doesn’t offer a camera washer, requiring manual cleaning.
To help make backing out of a parking space safer, the Ioniq 9 has standard Rear Cross-Traffic Collision Warning with Rear Cross-Traffic Collision-Avoidance Assist, systems which detect vehicles approaching from the sides and can automatically apply the brakes to prevent a collision. Only the CX-90 Premium Plus/Turbo S offers Rear Cross Traffic Braking.
Both the Ioniq 9 and the CX-90 have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras, rear cross-path warning, driver alert monitors and available around view monitors.