World Blind Union Office
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Toronto, ON M4G 3E8
Telephone: 1-416-486-9698
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E-mail: info@wbuoffice.org
WBU External Position Statement
Hybrid/Quiet Vehicles
Approval:
Date Reviewed: February, 2013
By WBU Officers
Author: Mobility & Transportation Working Group, 2008-2012
Mitch Pomerantz, Chair
Note:
Executive Summary:
The World Blind Union (WBU) is a non-governmental organization
representing the interests of approximately 285 million blind and
partially sighted persons world-wide. Pursuant to a resolution passed
at the WBU’s 7th General Assembly in 2008, an initiative was
incorporated into the WBU's 2008-'12 Workplan to task the Mobility
and Transport Working Group with drafting a position statement on the
issue of hybrid/silent vehicles, including strategies to inform and
educate WBU members and to offer approaches for addressing this
growing problem. This paper outlines WBU's position relative to the
increasing prominence of such vehicles. It draws heavily from one
previously prepared by the European Blind Union and we wish to
acknowledge their efforts.
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Background
Since the mid-2000's, hybrid and electric vehicles have become
popular among an increasingly environmentally sophisticated
population concerned about air pollution and its impact on health,
rising fuel prices, and the need for new direction for a struggling
automobile industry. Blind and partially sighted people around the
world welcome this trend as long as the technology does not
jeopardize our safe and independent mobility.
Hybrid vehicles operate on a fuel-powered engine when driving above
20 MPH (32 KPH) and revert to a virtually silent electric motor when
idling or traveling at slower speed. All-electric cars such as the
Chevrolet Volt and the Smart Car operate silently without the usual
engine noise, regardless of speed. Such vehicles pose a serious threat
of injury or death to persons relying mainly on their hearing to assess
whether it is safe to cross streets or in other hazardous areas (e.g.
parking lots). Other pedestrians such as children, seniors, runners,
cyclists, or merely inattentive walkers are also at increased risk. In
their current stage of development, hybrid and electric vehicles are not
fully in line with universal design principles.
According to experiments conducted by researchers at the University
of California Riverside, vehicles operating in electric mode can be hard
to hear below 20 MPH (32 KPH). Above that speed the sound of tires
and air flowing over the vehicle start to make it audible. Researchers
determined that a Toyota Prius needed to be as much as 65 percent
closer to test subjects than a car with a standard internal combustion
engine before testers could judge its direction correctly. During the
tests, the Prius was not heard until it was 10 feet (3.30 meters) from
blindfolded volunteers. A recent study authorized by the United States
National Highway Traffic Safety Administration in 12 states showed a
50 percent higher rate of accidents involving pedestrians for hybrids
than for standard internal combustion vehicles.
Progress and Current Status
The WBU adopted a resolution on this subject at its 7th General
Assembly in 2008. The resolution called upon "all regions where large
numbers of vehicles are in use to advocate for research into
technologies and standards to identify independently vehicles while
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traversing streets or other areas where vehicles may be encountered,"
and "the United Nations and national governments to adopt a standard
of sound adequate to alert pedestrians to the presence, speed, and
direction of vehicles within the environment."
Regarding the first imperative, serious research into what would
constitute an appropriate warning sound commenced in 2010. Noise
generators for quiet cars have been studied by Warwick University in
the United Kingdom. In the U.S., General Motors has been conducting
tests using sounds which closely imitate those of gasoline powered
engines. Fiat, Lotus and Nissan have recognized the problem and
have also been involved in various stages of research and testing.
Japan has looked into developing guidelines, or even mandating
minimum noise levels for such vehicles.
Regarding the second imperative, the United Nations has been working
to address the hazard posed by quiet vehicles to the safety of blind
people and other pedestrians. The World Forum for Harmonization of
Vehicle Regulations (WP.29), "Working Party on Noise" (GRB) created
the Quiet Road Transport Vehicle (QRTV) working group charged with
developing guidelines for designing alert sound devices. In early 2010,
as the QRTV was working on developing voluntary guidelines, the
National Federation of the Blind and the American Council of the Blind
were able to persuade the United States Congress to adopt legislation
mandating a minimum sound standard for hybrid electric and other
quiet vehicles. As a result of the U.S. law, the United States and Japan
proposed that the GRB develop a Global Technical Regulation, rather
than voluntary guidelines.
A new working group was formed in mid-2012 to draft the text of the
Global Technical Regulation. Thus far, the group has met twice, in midJuly and in December 2012. Developing a Global Technical Regulation
is complex and will involve reaching international agreement on a
number of issues of immediate concern to blind individuals.
Key Issues
While there is consensus on developing a Global Technical Regulation,
specifics about what that regulation should be are undecided.
Engineers are still determining what kind of alert sound would be
easily recognized as a motor vehicle, what sound level will provide
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reasonable safety, and at what speed does the sound of the tires on
the pavement and wind emit enough warning that the alert sound is
no longer needed (cross-over speed). The WBU must provide direction
on these issues so that the Global Technical Regulation fully protects
the right of blind people to travel safely and independently.
Replicating the sound of a conventional internal combustion vehicle is
difficult, but it is important that the alert sound be one that is
intuitively recognizable as coming from a vehicle. If the sound is not
identical to that of an ordinary car, it must be close enough that the
pedestrian will recognize it without the need for significant training.
Additionally, the Global Technical Regulation must not specify a sound
level so minimal as to compromise the safety of blind and other
pedestrians. In working to find a reasonable balance between a quiet
sound that puts blind pedestrians in danger and a loud sound that
disturbs people, safety should be the highest consideration. Regarding
the cross-over speed, sound engineers have determined that vehicles
emit more sound as the speed of the vehicle increases. When the
naturally occurring sound made by the vehicle reaches the same level
as the alert device, the alert sound is no longer needed. Determining
the correct crossover speed is essential to ensuring that blind
pedestrians are able to detect the presence of a quiet vehicle from a
safe distance.
Other questions persist, like should a minimum sound standard apply
solely to hybrid electric and electric vehicles or should it also apply to
quiet vehicles using internal combustion engines? Do hybrid electric
and electric vehicles need to make an alert sound while temporarily
stopped, and if so, should the same requirement apply to internal
combustion engines using stop/start technology? If not, should
vehicles come equipped with an on-off switch allowing the driver to
disable the alert sound? Does the alert sound need to change in pitch
as the vehicle accelerates and decelerates? The WBU must take a
position on these questions so that the safety of blind pedestrians is
not compromised by the Global Technical Regulation.
Hybrid electric and electric vehicles are virtually silent at low speeds,
and internal combustion engines are becoming increasingly quiet,
potentially posing the same hazard to blind and other pedestrians as
vehicles operating on electric power. Because of this, the minimum
sound standard should apply to any quiet vehicle regardless of its
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power source. Furthermore, both types of vehicles need to make an
alert sound while temporarily stopped, (i.e. at a traffic light), because
a stationary vehicle may begin to move at any time. If the blind
person is unaware of the presence of the car, he or she may step out
unexpectedly just as the driver begins to accelerate. Vehicles
operating on electric power begin moving more quickly than standard
vehicles, and some newer internal combustion engines with start/stop
technology literally shut off the engine and are silent while stopped. It
is critical for the pedestrian to be aware of the presence of a vehicle
that may suddenly start moving.
Although it has been argued that there is no need for the vehicle to
emit an alert sound when on a highway with no pedestrian traffic or
during a late drive through a quiet residential neighborhood, allowing a
driver to turn the device off would compromise the safety of blind
people and other pedestrians. The driver, however well intentioned,
may forget to turn the device back on or may falsely believe that he or
she is in a situation in which the device is not needed. The WBU
objects to an on-off switch because of the potentially dangerous
consequences.
Finally, it is generally understood that a change in the pitch of the
alerting sound should increase as the vehicle increases speed and
decreases as the vehicle slows. Today's internal combustion engines
naturally change in pitch in response to a change in speed. This is
known as pitch shifting. Blind people rely on changes in the pitch of
internal combustion engines to make judgments about when it is safe
to cross a street and to monitor the vehicle's movement. Therefore,
the design of an alert sound device must incorporate pitch shifting to
indicate changes in the vehicle's speed.
WBU Action Items
The World Blind Union urges all member nations to push for a Global
Technical Regulation to have a minimum sound standard that:
a. Is similar in character to the sound emitted by an internal
combustion engine;
b. Requires sound be emitted whenever the vehicle is in operation,
including when stopped;
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c. Applies to any quiet vehicle including electric, hybrid electric and
quiet internal combustion engines; and
d. Prohibits the inclusion of a driver controlled on/off switch.
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