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Bicycle Fact Sheets:
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| Geography | Population 2000 Census | Workers 2000 Census | Bike_to_Work 2000 Census | Percent of Mode Share | BFW Members November 2005 |
| Wisconsin | 5,363,675 | 2,690,704 | 11,635 | 0.43% | 2,249 |
| Out of State | n/a | n/a | n/a | n/a | 208 |
| Dane | 426,526 | 242,542 | 4,216 | 1.74% | 815 |
| Milwaukee County | 940,164 | 427,620 | 1,234 | 0.29% | 389 |
| Portage | 67,182 | 35,088 | 527 | 1.50% | 29 |
| Winnebago | 156,763 | 81,109 | 418 | 0.52% | 53 |
| Sheboygan | 112,646 | 58,546 | 401 | 0.68% | 41 |
| La Crosse | 107,120 | 55,971 | 359 | 0.64% | 30 |
| Outagamie | 160,971 | 84,571 | 350 | 0.41% | 33 |
| Brown | 226,778 | 118,872 | 293 | 0.25% | 65 |
| Waukesha | 360,767 | 192,602 | 276 | 0.14% | 165 |
| Eau Claire | 93,142 | 48,603 | 250 | 0.51% | 28 |
| Fond du Lac | 97,296 | 50,732 | 236 | 0.47% | 14 |
| Racine | 188,831 | 89,494 | 224 | 0.25% | 51 |
| Manitowoc | 82,887 | 42,406 | 222 | 0.52% | 14 |
| Marathon | 125,834 | 65,680 | 171 | 0.26% | 32 |
| Rock | 152,307 | 75,033 | 135 | 0.18% | 41 |
| Jefferson | 74,021 | 39,264 | 131 | 0.33% | 28 |
| Grant | 49,597 | 24,705 | 130 | 0.53% | 4 |
| Dodge | 85,897 | 42,598 | 121 | 0.28% | 11 |
| Walworth | 93,759 | 48,172 | 114 | 0.24% | 36 |
| Sauk | 55,225 | 28,694 | 97 | 0.34% | 18 |
| Kenosha | 149,577 | 72,053 | 96 | 0.13% | 23 |
| Marinette | 43,384 | 19,991 | 93 | 0.47% | 4 |
| Wood | 75,555 | 36,803 | 88 | 0.24% | 25 |
| Ashland | 16,866 | 7,674 | 81 | 1.06% | 2 |
| Dunn | 39,858 | 20,248 | 70 | 0.35% | 6 |
| Chippewa | 55,195 | 27,294 | 69 | 0.25% | 4 |
| Pierce | 36,804 | 20,818 | 68 | 0.33% | 4 |
| Clark | 33,557 | 15,683 | 64 | 0.41% | 6 |
| Ozaukee | 82,317 | 43,544 | 62 | 0.14% | 54 |
| Columbia | 52,468 | 26,991 | 55 | 0.20% | 9 |
| Green | 33,647 | 17,997 | 51 | 0.28% | 14 |
| Waupaca | 51,731 | 24,979 | 48 | 0.19% | 13 |
| Langlade | 20,740 | 9,517 | 47 | 0.49% | 2 |
| Shawano | 40,664 | 19,667 | 46 | 0.23% | 4 |
| Washington | 117,493 | 63,620 | 46 | 0.07% | 38 |
| Monroe | 40,899 | 19,927 | 45 | 0.23% | 7 |
| St.Croix | 63,155 | 34,428 | 44 | 0.13% | 12 |
| Calumet | 40,631 | 21,913 | 43 | 0.20% | 9 |
| Crawford | 17,243 | 8,127 | 43 | 0.53% | 1 |
| Door | 27,961 | 13,614 | 43 | 0.32% | 13 |
| Lincoln | 29,641 | 14,319 | 41 | 0.29% | 3 |
| Douglas | 43,287 | 20,323 | 37 | 0.18% | 0 |
| Oneida | 36,776 | 16,791 | 33 | 0.20% | 17 |
| Trempealeau | 27,010 | 13,863 | 33 | 0.24% | 4 |
| Adams | 18,643 | 7,700 | 28 | 0.36% | 2 |
| Polk | 41,319 | 20,288 | 27 | 0.13% | 4 |
| Waushara | 23,154 | 10,288 | 27 | 0.26% | 3 |
| Barron | 44,963 | 22,214 | 26 | 0.12% | 4 |
| Vernon | 28,056 | 12,930 | 24 | 0.19% | 6 |
| Oconto | 35,634 | 17,444 | 21 | 0.12% | 9 |
| Rusk | 15,347 | 6,888 | 21 | 0.30% | 0 |
| Iowa | 22,780 | 12,467 | 19 | 0.15% | 5 |
| Richland | 17,924 | 8,794 | 19 | 0.22% | 0 |
| Sawyer | 16,196 | 6,979 | 18 | 0.26% | 4 |
| Bayfield | 15,013 | 6,542 | 15 | 0.23% | 5 |
| Green Lake | 19,105 | 9,465 | 15 | 0.16% | 10 |
| Burnett | 15,674 | 6,734 | 14 | 0.21% | 0 |
| Washburn | 16,036 | 7,015 | 14 | 0.20% | 1 |
| Buffalo | 13,804 | 7,129 | 13 | 0.18% | 1 |
| Jackson | 19,100 | 8,750 | 13 | 0.15% | 5 |
| Price | 15,822 | 7,322 | 12 | 0.16% | 1 |
| Lafayette | 16,137 | 8,421 | 11 | 0.13% | 1 |
| Kewaunee | 20,187 | 10,580 | 9 | 0.09% | 2 |
| Marquette | 15,832 | 6,513 | 8 | 0.12% | 2 |
| Taylor | 19,680 | 9,700 | 8 | 0.08% | 2 |
| Juneau | 24,316 | 11,220 | 7 | 0.06% | 3 |
| Forest | 10,024 | 3,961 | 6 | 0.15% | 2 |
| Iron | 6,861 | 2,806 | 5 | 0.18% | 0 |
| Vilas | 21,033 | 8,876 | 4 | 0.05% | 5 |
| Florence | 5,088 | 2,296 | 0 | 0.00% | 0 |
| Menominee | 4,562 | 1,365 | 0 | 0.00% | 0 |
| Pepin | 7,213 | 3,531 | 0 | 0.00% | 1 |
"Bicycling and the Environment" Fact Sheet
A short, four-mile round trip by bicycle keeps about 15 pounds of pollutants out of the air we breathe. (WorldWatch Institute: http://www.worldwatch.org/)
If the average person biked to work or shopping once every two weeks instead of driving, we could prevent the pollution of close to one billion gallons of gasoline from entering the atmosphere every year. (Interview with Patrick McCormick, Communications Director for the League of American Bicyclists in It All Adds Up to Cleaner Air Newsletter: http://www.italladdsup.gov/newsletter/fall04/experts.html)
Since 1982, while the U.S. population has grown nearly 20 percent, the time Americans spend in traffic has jumped an amazing 236 percent. In major American cities, the length of the combined morning-evening rush hour has doubled, from under three hours in 1982 to almost six hours today. (Center for Transit Oriented Development: http://www.newurbanism.org/pages/496683/page496683.html?refresh=1116595957683)
In 1982, Boston drivers wasted 40 million gallons of gasoline simply sitting in traffic; by 2002, that number had increased to 130 million gallons. (Texas Transportation Institute 2005 Urban Mobility Report: http://tti.tamu.edu/documents/mobility_report_2005_wappx.pdf)
60% of the pollution created by automobile emissions happens in the first few minutes of operation, before pollution control devices can work effectively. Since "cold starts" create high levels of emissions, shorter car tripswhich can easily be bicycledare more polluting on a per-mile basis than longer trips. (bicyclinginfo.org, Pedestrian and Bicycle Information Center: http://www.bicyclinginfo.org/pp/benefits/enviroben/index.htm).
Nationwide, motor vehicle exhaust contributes 55% of nitrogen oxides, and 60% of carbon monoxide emissions, including as much as 95% of carbon monoxide pollution in urban areas. (The U.S. Environmental Protection Agency - Air Pollutants, Carbon Monoxide and Nitrogen Oxides: http://www.epa.gov/ebtpages/airairpollutants.html)
Air pollution contributes to the deaths of 70,000 people nationwide, more than the total deaths from breast and prostate cancers combined. (Harvard School of Public Health Press Release Air Pollution Deadlier Than Previously Thought March 2, 2000: http://www.hsph.harvard.edu/press/releases/press03022000.html).
Diesel engine emissions are responsible for 125,000 cancers nationwide, including an estimated 2,900 in Boston alone. (State and Territorial Air Pollution Program Administrators and the Association of Local Air Pollution Control Officials, Cancer Risk from Diesel Particulate: National and Metropolitan Area Estimates for the United States, March 15, 2000: http://www.4cleanair.org/comments/Cancerriskreport.PDF)
Originally Compiled by Sarah Hencke for MassBike
"Bicycling and Health" Fact Sheet
A 15-minute bike ride to and from work five times a week burns off the equivalent of 11 pounds of fat in a year. ( The British United Provident Association: http://www.bupa.co.uk/health_information/html/healthy_living/lifestyle/exercise/cycling/cycling_health.html)
64% of adults and over 15% of kids are overweight today, resulting in 300,000 premature deaths and a cost to society of $117 billion a year. More than 50% of U.S. adults do not get enough physical activity to provide health benefits: 26% are not active at all in their leisure time. (Center for Disease Control and Prevention Overweight and Obesity FAQ: http://www.cdc.gov/nccdphp/dnpa/obesity/faq.htm, and Physical Activity and Good Nutrition: http://www.cdc.gov/nccdphp/aag/aag_dnpa.htm )
Inactivity is a factor in 10% of total deaths and 25% of chronic disease related deaths. (League of American Bicyclists: http://www.bikeleague.org/educenter/factsheets/commutepublichealth.htm)
One reason for Americans' sedentary lifestyle is that "walking and cycling have been replaced by automobile travel for all but the shortest distances." (CDC: October 27, 1999 issue of the JAMA)
On 350 calories one apple tart a cyclist can travel 10 miles, a pedestrian 3.5 miles, and an automobile 100 feet. (Transportation Alternatives: http://www.transalt.org/blueprint/chapter1/chapter1g.html)
For every extra 30 minutes commuters drive each day, they have a 3 percent greater chance of being obese than their peers who drive less. How much time a person spends driving has a greater impact on whether a person is obese than other factors such as income, education, gender or ethnicity. (Obesity Relationships with Community Design, Physical Activity, and Time Spent in Cars, Frank LD, Andresen MA, Schmid TL. American Journal of Preventive Medicine 2004 Aug;27(2):87-96.: http://www.scarp.ubc.ca/faculty%20profiles/frank-paper.pdf )
Even though cyclists breathe two to three times as much air as
motorists during the same trip, motorists actually breathe in about 60%
more carbon monoxideand significantly higher levels of other air
pollutantsdue to being enclosed in their vehicle. Cyclists also
benefit from the physical exercise, increasing their resistance to air
pollution. ( The exposure of cyclist, car drivers and pedestrians
to traffic-related air pollutants, Van Wijen, Verhoeff, Henk, Van
Bruggen. Environmental Health 67 pp 187-193: http://europe.eu.int/comm/environment/cycling/cycling_en.htm)
Originally Compiled by Sarah Hencke for MassBike
Bicyclist Injuries: Learning from the Statistics
by Paul Schimek, Ph.D.
Public Health Data Sources Crash Types Falls
Car-Bike Collisions Experience Sidewalk Riding Head
Injury
Bicycling Can Improve Public Health
Improving bicycle safety means reducing the number and severity of injuries
related to bicycling. It may seem that not bicycling is safer than bicycling,
but this might not be so. Those who bicycle frequently enjoy better than
average health. Therefore from a broader perspective, including the effect
of regular exercise on disease, more bicycling has the potential to improve
both individual and public health. The Surgeon General has declared that
lack of exercise is dangerous to your health. This potential to improve
overall public health can only be realized if the injury and fatality
rate can be reduced.
Bicycle-related injury and fatality rates can be reduced by preventing crashes and reducing the risk of injury, or at least its severity, should a crash occur. ("Crash" is a better term than "accident"see below.) Bicyclists can use helmets, if fitted properly, to substantially reduce the risk of a head injury in the event of a crash. This is crucial because head injuries are responsible for most permanent and fatal injuries which happen to cyclists. Cycling gloves can prevent major injuries when the hands are used to break a fall. Although more widespread helmet use can reduce the incidence of fatalities and serious and permanent injuries, some fatalities, many serious injuries, and the majority of non-serious bicycle injuries can only be prevented by reducing the crash rate.
Because bicycling is a low-impact activity, if crashes can be avoided it is one of the safest forms of aerobic exercise and an easy way for those out of shape to gradually become more fit. Americans do not get enough exercise: "Despite common knowledge that exercise is healthful, more than 60 percent of American adults are not regularly active, and 25 percent of the adult population are not active at all" (CDC 1996).
Incorporating exercise into ones daily routine is necessary to get the regular exercise that health promotion experts advise ("30 minutes of physical activity of moderate intensity [such as brisk walking] on most, if not all, days of the week) (CDC 1996). Cycling for transportation is one way people can get a daily workout without making time for exercise.
Definitions and Data Sources
Highway safety specialists now use the term "crash" instead
of the term "accident" to emphasize the fact that most crashes
are predictable, preventable events. Bicycles are single-track, balance
vehicles: a bicyclist can sustain an injury simply by falling, without
a prior collision. Bicycle collisions are almost always followed by a
fall. As used here, a fall is an event not proceeded by a collision. Bicycle
crashes are the sum of all falls and collisions.
Studying bicycle crashes helps in identifying countermeasuresmethods
to prevent future crashes. Data on previous crashes come from several
sources:
Bicyclist surveys. This is the only method providing both complete event data (minor and major injuries) and some data on "exposure" (number of miles ridden), but provides no information on fatalities.
Hospital records. These in theory could provide complete data on injuries that were serious enough to require a visit to an Emergency Room.
Police records. In most jurisdictions, only crashes involving at least one motor vehicle are recorded, so the majority of bicycle crashes (those that do not involve motor vehicles) are not even eligible to be reported. In Moritzs 1998 study, 28% of bicycle crashes with $50 or more of property damage or medical expenses were reported to the police.
All of these sources provide some valuable information and are necessary to provide a complete picture.
Types of Crashes
The share of crashes by type is shown in Table 1 for both bicycle club
members and bicyclists visiting emergency rooms. The data show that 50%
to 60% of all crashes are falls. The next most common type of crash is
a collision with a fixed object. These two types together account for
75% to 80% of all bicycle crashes.
Falls and crashes with fixed objects happen because of problematic surface
conditions and/or bicycle operator error. Many falls produce very minor
injuries, but others can result in major injuries or even fatalities.
Most bicycling injuries are the result of falling (hitting the ground),
whether preceded by a collision or not.
Table 1 Percentage Distribution of Crash Types from Two Studies
The data show that only a minority of bicycle crashes are due to automobiles. As shown in Table 1, car-bike collisions represented 11% of the total reported by club members, and 15% of those reported by emergency rooms. Although car-bike collisions are a small proportion of all bicycle crashes, they are the largest cause of fatal bicycle crashes.
For bicycle club members, bike-bike collisions are almost as common as bike-car collisions. Such collisions can be serious, even fatal, as can collisions with pedestrians and dogs. (Pedestrians can also be injured or even killed by colliding with bicyclists.)
Falls
Since falls account for such a large share of bicycle crashes, it is helpful
to understand the different types of falls and their countermeasures.
The most serious type of fall is a stopping fall, which occurs when the
front wheel suddenly stops moving: the cyclist does not and is launched
off the bicycle, often landing head first. These falls can occur if the
wheel falls into a road defect such as parallel drain grate slots, parallel
cracks, or bridge expansion joints; if a stick or piece of metal gets
caught in the wheel and hits the front fork, acting like a brake; or if
the cyclist hits a curb head-on or applies the front brake very hard.
Countermeasures include eliminating poor surface conditions and dangerous
road features (such as certain types of drain grates and expansion joints),
keeping roads and paths free of debris such as sticks, and training cyclists
to avoid these hazards and in proper use of brakes.
Skidding falls happen when the rear wheel slides out. They typically occur
when turning, and when something slippery has reduced the friction between
road and tire. Countermeasures include eliminating slippery areas (e.g.
some types of paint and thermoplastic, metal grate bridges, and metal
covers), improving maintenance to remove sand, gravel, wet leaves, oil,
and ice from the roadway, and training cyclists to avoid such areas or,
at the least, coast over them without turning.
Diverting falls happen when the cyclist is prevented from turning the front wheel into the lean to maintain his or her center of gravity. These falls can occur when the cyclist rides next to a parallel ridge such as a streetcar track or any seam or ridge in the road. Metal grate bridges and railroad tracks crossing the road at an angle can also produce this type of fall. Countermeasures include removing these road features where possible, and training cyclists about these hazards and the need to either avoid them or deliberately steer over them.
Insufficient speed falls are generally the least serious type. They happen when a cyclist does not, or cannot, remove a foot from a toe clip or "clipless" pedal system soon enough, or when he or she intends to go forward but is suddenly blocked by traffic. The only countermeasure is to improve cyclists use of clips and pedal systems.
Car-Bike Collisions
Most car-bike collisions, about 80%, happen when either the cyclist or
motorist is turning or crossing, usually at an intersection or driveway
(Hunter et al 1996; other studies have found very similar figures). The
share of collisions at intersections is even higher for urban areas (89%),
and most car-bike collisions happen in urban areas (also 89%), because
that is where most cycling occurs (Forester 1994). Bikes and cars collide
at intersections when they are approaching from opposite directions or
when one is turning and the other continuing straight.
The most detailed analysis of car-bike collisions can be found in Foresters
Bicycle Transportation, pp. 46-54 (1994). His analysis is based on data
from 919 car-bike collisions in four metropolitan areas collected in a
study sponsored by the National Highway Traffic Safety Administration
(Cross and Fisher 1977). The Hunter et al. (1996) study provides more
recent data of the same type, but the published reports do not permit
a detailed analysis of the circumstances of collisions. The frequency
distributions of crashes by crash type in the two studies are very similar.
Although they are the most feared of all bike crashes, fewer than 10% of car-bike collisions occur when the motorist is overtaking. When they happen, it is usually in rural areas or at night, or when the motorist is impaired or drunk (Foresters [1994] analysis of Cross and Fisher 1977).
In his analysis of the Cross and Fisher data, Forester found that the cyclist was riding in the roadway in the direction of traffic in only 37% of all car-bike collisionsin the remaining cases, the majority, the cyclist was entering the roadway, riding against traffic, turning or swerving from the curb lane, or riding on the sidewalk. In general, bicyclists are more likely to be at fault (in the sense of disobeying the rules for drivers of vehicles) than motorists when the two collide. The figures in the 1996 Hunter et al. study reveal that the bicyclist was solely at fault in 54% of cases, the motorist solely in 30%, and both were at fault in 30% of car-bike collisions where culpability was determined.
Foresters analysis shows that car-bike collisions can be grouped by age of cyclist: child (under 13), teen, and adult. Most victims of bike crashes in which the cyclist rides out into traffic are children. Children also account for most of the crashes in which the cyclist swerves or runs a stop sign. Teen cyclists seem to have learned to avoid ride-out and swerving crashes, but they have more intersection crashes, with causes including wrong-way cycling, sidewalk cycling, and turning left from the curb lane. Adults have mostly learned to avoid the mistakes that teens and children make, but they are subject to a variety of crashes involving motorist error, some of which can be avoided by riding skills such as proper lane positioning and emergency maneuvers.
A study of car-bike collisions in the Boston metropolitan area (Plotkin and Komornick 1984) revealed a high incidence of bike hitting car door crashes; these represented 5.3% of all crashes compared to 0.8% in the Cross and Fisher (1977) study. By comparison, motorist overtaking crashes represented only 3.5% of the total. The high rate of car-door collisions and the low rate of overtaking collisions is because the crashes studied were all in urban areas (towns inside Rt. 128), and may be related to the narrow travel and parking lanes common on many urban roads in the area.
Wrong-Way Cycling Cycling against traffic is one of the most dangerous cycling behaviors. The obvious danger of a head-on collision with a lawful cyclist or motorist is only one of several types of crashes caused by wrong-way cycling. A motorist pulling out from a stop sign, commercial driveway, or turning right at a stop sign or traffic signal (including right turn on red) looks in the direction of traffic, not in the direction of the wrong-way cyclist, and then often has no time to avoid a collision. Cyclists riding against traffic accounted for nearly 1/3 of car-bike collisions in the Hunter et al. 1996 study and ¼ in the Boston area study (Plotkin and Komornick 1984).
Red-Light Running In the Boston study, 6.5% of car-bike collisions, a relatively high share, were caused by the cyclist entering the intersection on a red signal (by comparison, in only 2% of crashes did the motorist run a stop sign or red light). Many cyclists in the Boston area (and elsewhere) routinely ignore traffic signals and stop signs. One contributing factor is the lack of enforcementin most places in the Commonwealth, police departments never give citations to cyclists. Another contributing factor is the traffic lights themselves: many are controlled for at least some portion of the day by an actuator that consists of a loop of wire buried under the asphalt. An unknown percentage of these detectors are set so that they are insensitive to the amount of mass on a bicycle. When a cyclist is the first to arrive on a red light at such an intersection, he or she will not receive a green light until a motorist arrives to trigger the signal. This lack of responsiveness encourages cyclists to go through on red; and indeed, in some cases (such as a side street crossing a main road late at night), the alternative to entering on red may be waiting for a very long time.
Motorist Left and Right Turn The motorist left turn collision occurs when a motorist turns left into an intersection or driveway and hits a cyclist coming from the opposite direction. This is the most common motorist-caused car-bike collision, accounting for 7.6% of urban car-bike collisions in the Cross and Fisher (1977) study and 10.2% in the Boston study (Plotkin and Komornick 1984).
The motorist right turn collision occurs when a right-turning motorist collides with a cyclist to his or her right. It can occur when the motorist has overtaken too close to the intersection, when a cyclist passes on the right, or when the two are parallel, with the cyclist in the motorists blind spot. This type accounted for 4.8% of collisions in the Cross and Fisher study and 6% in the Boston area study.
Both of the motorist turn collisions are more likely to occur to adults, which perhaps explains their higher representation in the Boston area, where apparently there is a higher share of adult cyclists compared to the national average. Although these two accident types together account for only 12% to 16% of car-bike collisions, they are a much higher percentage of the collisions which occur to cyclists riding on the roadway with the flow of traffic.
A cyclist can reduce the risk of a motorist left turn collision by being more visible by (1) using a head light at night and (2) riding close to the stream of traffic, not near the curb (nor on the sidewalk). A cyclist can potentially avoid an incipient left-turn collision by turning right, inside the motorists turn. Making such a sharp turn is usually possible only if the cyclist has previously practiced making forced turnstaking advantage of the counter-steering principle to get the bicycle leaned over quickly by steering very briefly to the left, and then immediately bring the wheel back to the right and leaning into the turn.
A cyclist can reduce the risk of a motorist right turn collision by moving to the center of the right lane, certainly to the left of any right-turn only lane, when approaching an intersection; by never passing on the right side of a moving motor vehicle, especially not at an intersection or driveway; and by waiting in front or behind, not beside, a stopped motor vehicle when waiting to proceed at an intersection. A cyclist can also potentially avoid an incipient right-turn collision by turning right, inside the motorists turn, in the same manner as described above.
Nighttime Safety Certain types of car-bike collisions occur disproportionately at night, including motorist entering from side street or on-street parking, motorist turning left, motorist overtaking, and wrong-way cyclist hit head-on (Forester 1994 based on Cross and Fisher 1977). In the first two of these crash types, the motorist must yield to the bicyclist already in the road, but the motorists headlamps will not be shining on the bicyclist. Therefore the bicyclist needs, and is required by law to use, a headlight to be seen by vehicles in these situations. A significant number of motorist overtaking collisions occur when the cyclist was unseen at night. Increasing the cyclists conspicuity from the rear by equipping the bicycle with a red tail light and a brighter, automotive reflector instead of a bicycle reflector, is the key countermeasure for this crash type. None of the crash studies have information on the lack of required nighttime equipment among bicyclists hit. However, because very few of those cycling at night use lights, the contribution of this behavior to the bicycle crash problem is likely to be high. In a Boston study, 15% of cyclists were observed using either a headlight or taillight at night (Osberg, Stiles, and Asare 1998). The headlight is required in Massachusetts (and every other state), although a rear reflector alone meets the legal requirements. Although not required, tail lights are highly desirable and are probably more in use then headlights currently, since low-power, battery-powered red LEDs are available, and since cyclists are often more afraid of being hit from behind than from the front.
The Effect of Experience on Crash Rates
The more years and miles of cycling experience, the lower the crash rate.
College students have a lower crash rate than elementary school students,
but not by that much considering that college students are adults and
typically licensed drivers (see Table 2). Bicycle club members, on the
other hand, have a crash rate which is dramatically lower than both other
groups (and their crash rates were essentially the same in 1975 and 1996
surveys). Crash rates decline with years of experience, but more rapidly
if bicyclists participate in club rides where they may learn from the
example of other riders. More commonly, since club riders are a small
minority of bicyclists, new riders learn by trial and error to avoid dangerous
behaviors, as the above analysis of accident types shows. The learning
process takes some time because most cyclists receive no training, neither
in formal classes nor from riding with knowledgeable cyclists. On the
road, bad habits are rarely punished and safe and lawful riding is sometimes
discouraged. Since bicyclists are rarely stopped even for flagrant violations
of the traffic rules such as wrong-way riding, they may persist in their
bad habits. Further, the frequent advice given to cyclistsstay off
the road, or at least stay as far to the right as you possibly canmay
hinder the learning of skills such as riding to the left of a right-turn
only lane when proceeding straight or preparing well in advance to turn
left by merging to the center of the road. Cyclists who perform these
maneuvers correctly are sometimes told by motorists, or even police, to
get off of the road.
Table 2 Mean Annual Miles of Bicycling and Mean Crash Rates from Five Studies
Risk of Sidewalk and Wrong-way Riding
Bicyclists who habitually ride on the sidewalk and across crosswalks are
more at risk than those who ride on adjacent roadways. A 1994 study in
California compared the accident rate per mile of sidewalk riding compared
to the accident rate for road riding (on the same roads) and found that
the rate for sidewalk accidents was 1.8 times greater (Wachtel and Lewiston
1994).
The same California study found that the relative risk of riding the wrong way (against traffic) was 3.6 times as high for those riding with traffic. In Hunter et al. 1996, about 1/3 of all bicyclists hit by cars were riding against traffic. The Boston study found that about ¼ of all cyclists hit were riding against traffic.
Riding on the sidewalk opposite the flow of traffic is more than 4 times as dangerous as riding on the road with the flow of traffic. The California study found that this risk was 4.3 times greater than riding on the road with the direction of traffic.
Contrary to intuition, cyclists riding on bicycle paths (now called "shared use paths") have a higher crash rate than cyclists riding on roads, although not as high a crash rate as cyclists riding on sidewalks (Aultman-Hall and Kaltenecker 1998). The risk of injuries on paths compared to roads has been calculated as 40%, 80%, and 260% higher (Moritz 1998, Aultman-Hall and Kaltenecker 1998, Kaplan 1976). Some of the increased risk may be explained by the greater likelihood of inexperienced cyclists to use paths or sidewalks (Aultman-Hall and Adams 1998). However, the studies of bicycle club members, who are much more experienced than average cyclists, reveal a higher crash rate on paths even for these riders.
Preventing Head Injury
Helmets can only protect against head (including brain) and facial injuriesbut
these are the injuries most likely to be permanently disabling or fatal.
In a 1996 study, 35% of injured bicyclists admitted to emergency rooms
had facial injuries and 22% had head injuries (see Table 3). Extremities
were the most common location of injuries. The most common types of injuries
were abrasions, lacerations, and contusions. One-fourth of the patients
with bicycle-related injuries suffered fractures.
Table 3 Region of injury or injuries of Seattle-area bicyclists visiting
emergency rooms
Helmet Effectiveness Rivera et al found that 57% of injured cyclists without head trauma were wearing helmets, but only 24% of cyclists with severe brain injuries were wearing helmets. They calculated the implied reduction in risk of head and brain injury as approximately 70% (see Table 4). This figure may understate the effectiveness of helmets because it can be assumed that some bicyclists experiencing a crash did not have injuries requiring medical attention and therefore were not represented in the control group, bicyclists with non-head injuries. Table 4 also shows that helmets are effective in reducing upper facial area injuries, but not at all in lower facial injuries. The study also found that the risk reduction was about the same70%for all age groups.
Helmet Fit Helmets must be snug and low against the forehead for maximum effectiveness. The Harborview study (Rivara et al. 1996) asked injured cyclists or their parents to report on helmet snugness, position on the head, use of pads, adjusting of straps, if the helmet covered the forehead, and whether the helmet could be removed while the strap was still fastened. Cyclists who reported their helmets fit poorly were almost twice as likely to suffer head injury as cyclists whose helmets fit best (Rivara et al. 1996). They found that cyclists whose helmets came off during a crash were three times more likely to have head injuries than cyclists with snug helmets. The study also found that parents assessment of fit did not correspond well to that of trained personnel using standard protocols.
Table 4 Relative risk reduction of Seattle-area bicyclists visiting emergency rooms
Summary on Helmets The evidence indicates that helmets are effective in reducing head and face injuries. Since head injuries account for most of the serious and fatal injuries that happen to cyclists, wearing a helmet is very important. Other injuries, while more common, tend to be less serious and usually result in a complete recovery. Helmets are much more effective if they fit properly. Helmets should be used when cycling in any location, even where there is no motor traffic, since any fall can result in head injury, and falls are by far the most common cause of injury.
References
Aultman-Hall, Lisa and Michael F. Adams, Jr. 1998. Sidewalk Bicycling Safety Issues. Paper presented at the Transportation Research Board. 77th Annual Meeting.
Aultman-Hall, Lisa and M. Georgina Kaltenecker. 1998. Toronto Bicycle Commuter Safety Rates. Paper presented at the Transportation Research Board. 77th Annual Meeting.
The Centers for Disease Control and Prevention (CDC). 1996. Physical Activity and Health: A Report of the Surgeon General.
Cross, Kenneth D. and Gary Fisher. 1977. A Study of Bicycle/Motor Vehicle Accidents: Identification of Problem Types and Countermeasure Approaches. National Highway Traffic Safety Administration.
Forester, John. 1994. Bicycle Transportation. Cambridge, MA: MIT Press.
Hunter, William W. Jane C. Stutts, Wayne E. Pein, and Chante L. Cox. 1996. Pedestrian and Bicycle Crash Types of the Early 1990s. U.S. Department of Transportation. FHWA-RD-95-163.
Kaplan, Jerald A. 1976. Characteristics of the Regular Adult Bicycle User. FHWA. National Technical Information Service. Washington, DC.
Moritz, William E. 1998. Adult Bicyclists in the United StatesCharacteristics and Riding Experience. Transportation Research Board. 77th Annual Meeting.
Osberg, J. Scott, Sarah C. Stiles and Ohene Kwaku Asare (1998) Bicycle Safety Behavior in Paris and Boston. Accident Analysis and Prevention 30, 5, 679-687.
Plotkin, Wendy and Anthony Komornick, Jr. 1984. Bicycle-Motor Vehicle Accidents in the Boston Metropolitan Region. A Study of Reported Accidents Occurring within Route 128 in 1979 and 1980. Boston, MA: Metropolitan Area Planning Council.
Rivara, Frederick P., Diane C. Thompson, and Robert S. Thompson. 1996. Circumstances and Severity of Bicycle Injuries. Snell Memorial Foundation. Harborview Injury Prevention and Research Center.
Wachtel, Alan and Diana Lewiston. 1994. Risk Factors for Bicycle-Motor Vehicle Collisions at Intersections. ITE Journal. September. pp. 30-35.
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