NHTSA Rulemaking Activities for Quiet Vehicles Alert Sound Standard

1. QRTV-07-08 NHTSA Rulemaking Activities for Quiet Vehicles Alert Sound Standard 7th Meeting of the Quiet Road Transport Work Group Osaka, Japan

2. Rulemaking Schedule • January 4, 2011 President Obama signs Pedestrian Safety Enhancement Act requiring NHTSA to issue a standard mandating alerts sounds for quiet vehicles in 36 months • Summer 2011 NHTSA begins Phase III Quiet Vehicles Research to develop compliance test procedures, performance metrics, and pass/fail criteria • July 12, 2011 NHTSA published Notice of Intent (NOI) to prepare an Environmental Assessment • August 11, 2011 comment period for NOI closes • Fall 2011 complete Phase III Research • July 5, 2012 release of proposed Quiet Vehicles Standard in Notice of Proposed Rulemaking and Environmental Assessment

3. Rulemaking Alternatives NHTSA believes that Alternatives 2-5 described in the NOI are all feasible approaches for a pedestrian alert sound regulation

4. Alternative 2 – Recording of Sounds from Internal Combustion Vehicles • Compliance would be based on acoustic parameters designed around ICE like sounds • Sound would be recognizable as a motor vehicle in operation • Represents low cost option for compliance – manufacturers are not required to develop synthetic sounds • Current soundscape is unchanged lessening concerns about annoyance caused by multiple sounds with different acoustic profiles

5. Alternative 3 – Synthesized ICE Equivalent Recording • Recorded ICE sounds processed by digital signal processor • Would have fewer spectral components than Alternative 2 • Compliance test would be similar to Alternative 2 • Possible that these synthetic sounds could have enhanced detectability • Sound would be recognizable as a motor vehicle in operation

6. Alternative 4 – Synthesized Non-ICE Sounds with ICE Components • Synthetically created ICE-like sounds with components that enhance detectability • Compliance test would include acoustic measurement for sound levels • Recognizability would be determined by jury testing or acoustic measurement • Greater likelihood that the sound will be recognizable • Potential to offer enhanced detectability • Could prove more acceptable to the public than other synthetic pedestrian alert sounds

7. Alternative 5 – Synthesized Non-ICE Sounds Developed to Enhance Detectability • Characteristics common to these sounds include pitch shifting, prominent harmonics in the 150 Hz to 4000 Hz range and four or more frequencies with an average sound pressure level above 50 dba. • Compliance test would include acoustic measurement for sound levels • Recognizability would be determined by jury testing or acoustic measurement • It is possible that these sounds will offer better detectability than ICE like sounds • multiple sounds with different acoustic profiles could prove annoying to the public

8. Requirements of Pedestrian Safety Enhancement Act • Alert sound must allow pedestrians to be able to discern “vehicle presence, direction, location, and operation” when the vehicle is operating below the crossover speed • Determine the sound level necessary to allow blind and sighted pedestrians “to reasonably detect a nearby electric or hybrid vehicle operating at or below the cross-over speed”