For enhanced safety, the front and rear seat shoulder belts of the Mercedes GLA have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The Acura RDX doesn’t offer pretensioners for its rear seat belts.
The GLA’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The RDX doesn’t offer pre-crash pretensioners.
The GLA’s standard pretensioning seatbelts also sense rear collisions and remove slack from the seatbelts to help protect the occupants from whiplash and other injuries. The RDX doesn’t offer a whiplash protection system.
The GLA offers an optional Post Collision Brake, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The RDX doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.
Both the GLA and RDX have rear cross-traffic warning, but the GLA has Active Brake Assist (automatically applies the brakes) to better prevent a collision when backing near traffic. The RDX’s Rear Cross Traffic Monitor doesn’t automatically brake.
The GLA’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The RDX doesn’t offer a driver alert monitor.
Both the GLA and the RDX have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, blind spot warning systems, rearview cameras, rear cross-path warning, available all wheel drive, lane departure warning systems and around view monitors.