How Fast Do Airbags Deploy MPH

Airbags do not deploy at one fixed vehicle speed or a single mph threshold. Deployment is based mainly on crash severity and the rapid change in speed detected by the vehicle’s sensors. For some frontal airbag systems, deployment in a moderate or severe crash may correspond roughly to an impact comparable to hitting a rigid barrier at around 10 to 16 mph for an unbelted occupant, but thresholds vary by vehicle and restraint design. That does not mean an airbag will always deploy whenever the speedometer shows 10, 15 or 20 mph. A vehicle can be travelling quickly without triggering an airbag if the collision does not create the required type of deceleration, while a lower-speed impact can sometimes produce deployment. Side and curtain airbags have separate sensors and deployment criteria. Seat-belt use, impact direction and other factors may also influence the restraint strategy. If deployment or non-deployment is important after a crash, vehicle data and an expert inspection are more reliable than estimating from road speed alone.