The NHSTA proposes to amend FMVSS 141
The National Highway Traffic Safety Administration (NHSTA) proposes to amend the test procedure in section S6.7.3 of Federal Motor Vehicle Safety Standard (FMVSS) No. 141.
The proposal mainly focuses on Minimum Sound Requirements for Hybrid and Electric. The original regulation, which was proposed on September 17, 2019, now is being amended to have to specify the single point in time that should be used when determining one-third octave band levels of ambient noise measurements in compliance testing.
The proposed regulations will continue to provide protection for pedestrians and other road users, because FMVSS No. 141 requires Hybrid and Electric Vehicles to emit a pedestrian warning sound under certain conditions. The warning sound of the vehicle is allowed to change depending on the speed or direction of operation. There are five different operating conditions defined by the Standard. This applies when the vehicle is stationary, in neutral or in forward gear and at a constant vehicle speed below 10 km/h, when reversing, at a constant vehicle speed from 10 km/h up to and including 20 km/h, from 20 km/h to 30 km/h and at or just above 30 km/h. Beyond this speed, warning sounds are not required by FMVSS No. 141.
Furthermore, Section 5.5 of the standard, titled “Requirement for Uniformity,” requires that two vehicles of the same make, model, model year, body type, and trim level have the same pedestrian warning sound in each operating mode. This final rule is effective on 12 August 2022.
The texts of the Regulation can be consulted HERE.