Since approximately half of all vehicle occupants that die in crashes are unbelted, NHTSA’s occupant crash protection standard (FMVSS No. 208) mitigates crash risk to unbelted occupants through performance requirements involving crash testing with unbelted dummies. To meet these performance requirements, manufacturers configure cabins in relatively homogenous manners and tailor air bag and knee bolster designs for unbelted occupants. Manufacturers may also be limited in their ability to optimize safety designs to protect properly belted occupants. This rulemaking would seek public comment on a potential regulatory action to implement a compliance option by which vehicles equipped with Seat Belt Assurance Systems (SBAS), which ensure proper seat belt use by outboard front seat occupants through an advanced detection system that limits vehicle functionality when front seat occupants are unbelted, are exempt from the current unbelted crash test requirements of FMVSS No. 208. This additional compliance option would remove the regulatory and testing burden associated with unbelted crash tests and associated design requirements for vehicles that ensure that the front seat occupants are belted.