ACB’s comments to the National Highway Traffic Safety Administration (NHTSA) concerning the Notice of Proposed Rule Making on the Pedestrian Safety Enhancement Act.

March 15, 2013
Department of Transportation
National Highway Traffic Safety Administration
49 CFR Part 571
Docket No. NHTSA-2011-0148
RIN 2127-AK93
Federal Motor Vehicle Safety Standards
Minimum Sound Requirements for Hybrid and Electric Vehicles

The American Council of the Blind (ACB) is pleased to provide comment on the Notice of Proposed Rule Making (NPRM) published on January 14, 2013 concerning minimum sound requirements for hybrid and electric vehicles.

ACB is a national membership organization whose purpose is to work toward independence, security, equality of opportunity, and improved quality of life for all blind and visually impaired people. Founded in 1961, ACB's members work through more than 70 state and special-interest affiliates to improve the well-being of all blind and visually impaired people by: serving as a representative national organization; elevating the social, economic and cultural levels of blind people; improving educational and rehabilitation facilities and opportunities; cooperating with the public and private institutions and organizations concerned with blind services; encouraging and assisting all people with severely impaired vision to develop their abilities and conducting a public education program to promote greater understanding of blindness and the capabilities of people who are blind.

Over all, ACB is encouraged by the contents of the NPRM. Once implemented, this promises to allow for a far greater degree of safety and security for all pedestrians who traverse the streets and roadways in this country.


  1. Sound During Stationary but Active: ACB supports NHTSA’s finding that “stationary but active” is a critical operating scenario during which vehicles must emit a level of sound that is adequate to be detectable by pedestrians who are blind or visually impaired. We appreciate NHTSA’s recognition of the importance of sound to the independent and safe travel of such individuals. With regard to the agency’s query as to whether a “commencing motion” sound would be appropriate in lieu of a “stationary but active” sound, ACB strenuously opposes this recommendation. Unless a blind pedestrian is made aware that a vehicle is likely to be set in motion at any time, he/she will not have an adequate opportunity to react safely once that vehicle begins to move. For this reason, we believe that the “stationary but active” sound is the only appropriate means of communicating a vehicle’s presence and likely movement in this situation.
  2. Crossover Speed: ACB supports NHTSA’s finding that under the provisions of the Pedestrian Safety Enhancement Act, an appropriate crossover speed should be 30 km/h (18 MPH).
  3. ACB believes that the second option set forth by NHTSA: setting the minimum sound levels for EVS and HVS based on the sound level produced by light ICE vehicles, is the most appropriate option since it is this sound level on which blind/visually impaired pedestrians rely for safe navigation.

Agency Requests for Comment

  1. The agency solicits comment on possible configurations of the alert sound that would lower or deactivate the alert sound in situations in which pedestrians are not present. One of the methods proposed for mitigating the noise caused by stationary EVs and HVs would be to allow the vehicle to reduce or turn off its sound after the vehicle had been stationary for a period of five to ten minutes. ACB concurs with the agency’s position that the Pedestrian Safety Enhancement Act prohibits the agency from allowing a driver to deactivate this sound. We agree with the agency’s position that “stationary” is a critical operating scenario that absolutely must be covered by this rule. There are many factors about the design of an intersection which people who are blind can only detect by evaluating audible cues created by the sound of vehicles. Both vehicles that are in motion and those that are stationary provide essential information. Appropriate evaluation of this information is imperative for safe pedestrian travel. Additionally, here are numerous situations wherein a vehicle may be left with the engine running and stopped across a pedestrian right-of-way, (e.g., where a sidewalk crosses a driveway). This is frequently the case with delivery vehicles whose operator may be gone for a significant length of time. On the streets, instances in which a vehicle extends into the crosswalk, engine running, are also not uncommon.
  2. The agency seeks comment on whether requiring a ``commencing motion sound'' is as an effective approach to implementing the requirements in the PSEA that an alert sound allow pedestrians to discern the ``presence, direction, location and operation'' of the vehicle as establishing minimum sound requirements for when the vehicle is activated but stationary. For the reasons stated previously, we believe that the establishment of minimum sound requirements for when a vehicle is “stationary but activated” is the only acceptable solution.
  3. The agency seeks comment on the speed at which alert sounds should activated/deactivated. As we alluded to above, ACB believes that 30 km/h (18 mph) should be the crossover speed for determining when alert sounds will be activated or deactivated. This contention is based on solid research and required to protect the safety of both pedestrians and drivers.
  4. The agency solicits comment on whether 500 milliseconds is a sufficient amount of time for the alert sound to activate after the vehicle’s starting system is engaged. ACB believes that it is.
  5. The agency seeks comment on whether a start-up sound should be included as an operating condition for which the agency should establish minimum sound and additional acoustic requirements. Since the alert sound should be activated any time a vehicle is activated, we do not believe there is any need for a specific “startup” sound.
  6. The agency seeks comment on whether the requirements in this proposal should apply to LSVs. ACB believes that low speed vehicles should be included in this rulemaking because of the very fact that they are traveling at speeds and in environments where they are likely to be in close proximity to pedestrians. If these vehicles are silent, this combination increases the risk of accidents.
  7. The agency seeks comment on whether the minimum sound level requirements proposed in this rule should apply to electric motor cycles. ACB does not believe there is any justification for exempting these vehicles from the minimum sound levels contained in this rulemaking. After all, they travel the same roadways as other hybrid and electric vehicles and can present pedestrians with the same safety challenges.
  8. The agency seeks comment on whether the application of this rule should be limited to vehicles with a gross vehicle weight rating of ten thousand pounds or less. The agency has indicated that introduction of hybrid and electric vehicles weighing greater than ten thousand pounds is forthcoming. There is no reason to think they won’t present the same dangers to pedestrians as their lightweight counterparts. Therefore, we believe they should be subject to the same standards.
  9. The agency also solicits comment on whether heavy duty vehicles that are equipped with a backup sound should be required to emit additional sound when moving in reverse. ACB believes that such a requirement is both redundant and unnecessary. In fact, backup sounds emitted by heavy duty vehicles are very recognizable and should be sufficient.
  10. Finally, the agency seeks comment on whether this proposal should include a maximum sound level requirement. ACB does not recommend that a maximum sound level requirement be established. These standards should remain flexible enough to allow for changes in the design of both vehicles and roadways that we cannot predict at this time.

This webpage last updated March 15, 2013.