RoSPA – 3. Motorcycle Accidents & Casualties

3.1 Despite forming only 1% of road traffic, motorcyclists account for 14% (one in seven) of road deaths and serious injuries. However, casualties amongst motorcyclists have dropped significantly from their 1981-1985 average. As can be seen in Table 5, motorcyclist fatalities have fallen by 45%, serious injuries by 68%, and slight injuries by 57%. Overall TWMV user casualties have decreased by 60%.

[table delimiter=”|”]
Table 5 : TWMV Casualties in Great Britain, 1981/85 and 1999[attr colspan=”4″]
Casualties| 1999| 1981-85| % change
Fatal| 547| 989| – 45
Serious| 6,361| 19,714| – 68
Slight| 19,284| 44,490| – 57
Total| 26,192| 65,193| – 60
[/table]

3.2 Worringly, the number of motorcyclists killed rose by 10% between 1998 and 1999, the number seriously injured rose by 7% and those slightly injured by 6% . This may be due to a 16% rise in motorcycle traffic between 1998 and 1999, which means that the motorcycle casualty rate by distance travelled fell by 8%. However, caution should be used when interpreting trends from changes in accident data from one year to the next.

3.3 The vast majority (94%) of motorcyclist casualties are riders, with passengers forming just 7% of casualties. Casualty reductions in absolute numbers for pillion passengers have been even greater than those for riders.

[table delimiter=”|”]
Table 6 : TWMV Rider and Passenger Casualties in Great Britain, 1981/85 and 1999[attr colspan=”4″]
Casualties| 1999| 1981-85| % change
Riders[attr colspan=”4″]
Fatal| 525| 861| – 39
Serious| 5,918| 17,649| – 66
Slight| 18,073| 39,945| – 55
Total| 24,516| 58,455| – 58
Passengers[attr colspan=”4″]
Fatal| 22| 128| – 83
Serious| 443| 2,064| – 78
Slight| 1,211| 4,544| – 73
Total| 1,676| 6,736| – 75
[/table]

3.4 Casualty Rates
While some of the changes in motorcyclist casualties may be attributed to the fall in motorcycle use, the motorcyclist casualty rate per billion kilometres travelled in 1999 had also fallen by 26% from its 1981 – 85 level.

3.5 Motorcyclist casualty rates are much higher than other road users, as can be seen in Table 7.

[table delimiter=”|”]
Table 7: Casualty Rates per 100 million vehicle kilometres by Road User Group, 1999[attr colspan=”4″]
Road user Group| Killed| KSI| All Severities
Pedal Cyclists| 4.1| 7.6| 544
TWMV Riders| 11| 140| 533
Car Drivers| 0.3| 3.4| 35
All Riders & Drivers| 0.4| 5.1| 41
[/table]

3.6 The casualty rate for motorcyclists is 15 times higher than that of car drivers, but similar to that of pedal cyclists. The fatality rate for motorcyclists is three times higher than for pedal cyclists, but 40 times higher than that for car drivers, reflecting the fact that motorcyclists are not protected by a vehicle body, seat belts or the other occupant protection systems that car drivers enjoy.

3.7 Vehicle Involvement Rates Vehicle accident involvement rates show that motorcyclists are more likely to be involved in accidents. Table 8 shows that motorcycles are seven times more likely to be involved in an accident than a car, and 14 times more likely to be involved in a fatal or serious accident.

[table delimiter=”|”]
Table 8: Vehicle Involvement Rates by Type of Vehicle, 1999[attr colspan=”4″]
Road user Group| Fatal| Fatal & Serious| All Severities
Pedal Cycles| 4.5| 80| 563
TWMVs| 13| 159| 592
Cars| 1.0| 11| 87
All Vehicles| 1.2| 13| 91
[/table]

3.8 Motorcyclist Casualties by Age
There is a clear relationship between motorcyclist casualties and age, as can be seen in Table 9. There are few casualties below the age of 16 years because two wheeled motor vehicles are generally not used by children. Moped users show a casualty peak between the ages of 16 and 19 years. Motorcycle and motorcycle scooter user casualties peak between 20 – 49 years. These patterns probably reflect usage patterns of different types of motorcycles.

[table delimiter=”|”]
Table 9: Motorcyclist Casualties by Age, 1999[attr colspan=”3″]
[attr colspan=”1″]| Moped Users[attr colspan=”3″]| Motorcycle and Scooter Users[attr colspan =”3″]
| Killed| KSI| All| Killed| KSI| All
0 – 15| 1| 26| 65| 2| 39| 93
16 – 19| 6| 266| 1,734| 38| 578| 2,415
20 – 29| 2| 96| 576| 170| 1,756| 6,527
30 – 39| 1| 44| 305| 173| 2,042| 7,225
40 – 49| 1| 29| 190| 75| 921| 3,002
50 – 59| 2| 25| 140| 29| 387| 1,314
60 +| 4| 33| 125| 19| 130| 412
All Ages*| 17| 527| 3,192| 508| 5,937| 21,421|
[/table]
* Includes age not reported.

3.9 Motorcyclist Casualties by Gender
Motorcyclist casualties are predominately male. Men account for 93% of motorcyclist deaths and 88% of total motorcyclist casualties.

[table delimiter=”|”]
Table 10: Motorcyclist Casualties by Gender, 1999[attr colspan=”4″]
| Male| Female| All
Killed| 508| 39| 547
KSI| 6,256| 651| 6,907
Total| 23,263| 2,920| 26,183
[/table]

3.10 Casualties by Location
Overall, almost three quarters (72%) of motorcyclist casualties occur on built-up roads (roads with a speed limit of up to 40 mph), even though such roads carry less than half of motorcycle traffic. The pattern differs for different types of motorcycle. Around 85% of moped and scooter casualties occur on built up roads, compared to around 70% of motorcycle casualties.

3.11 One quarter ( 26%) of casualties occur on rural roads (roads with a speed limit of over 40 mph). And just 1% of motorcyclist casualties occur on motorways, which carry 7% of motorcyclist traffic.

3.12 However, the pattern for motorcyclist fatalities differs: 60% of motorcyclist deaths occur on non built-up roads, 37% on built-up roads and 3% on motorways.

[table delimiter=”|”]
Table 11: Motorcyclist Casualties by Type of Roads, 1999[attr colspan=”4″]
| Killed| KSI| All
Motorways| 16| 148| 458
Built-up Roads| 195| 3,444| 16,039
Non Built-up Roads| 319| 2,789| 6,503
All Speed Limits*| 530| 6,381| 23,000
[/table]
* Includes speed limit not reported

3.13 Casualty rates by distance travelled show that built-up A roads have a significantly higher rate for motorcyclists than other types of road, followed by built-up minor roads.

3.14 An analysis of motorcycle accidents in Cheshire indicate a shift in the balance of casualties from urban to rural roads, along with an increase in the proportion of casualties who are killed or seriously injured.

3.15 Motorcyclist Casualties by Month
Motorcyclist casualties are highly seasonal. Fatalities and overall casualties peak during the Spring and Summer months, which probably reflects increased riding, and hence accident exposure, during this period.

[table delimiter=”|”]
Table 12: Motorcyclist Casualties by Month: 1999[attr colspan=”4″]
Month| Killed| KSI| All
January| 20| 299| 1,473
February| 21| 349| 1,438
March| 43| 531| 2,042|
April| 51| 570| 2,072
May| 64| 740| 2,499
June| 54| 677| 2,459
July| 72| 914| 2,876
August| 71| 698| 2,552|
September| 45| 655| 2,470
October| 51| 598| 2,420
November| 39| 548| 2,364
December| 16| 329| 1,527
[/table]

3.16 Casualties by Time and Day
Fridays have the highest number of motorcyclist casualties, followed by the other days of the week which each have a similar level. The number of weekend casualties is slightly lower. During the week, motorcyclist casualties peak between the hours of 4:00 pm and 6:00 pm and between 7:00 am and 9:00 am. At the weekend, powered two wheeler casualties are more evenly spread throughout the day, with a slight peak between midday and 6:00 pm. This is similar to the pattern for all road users.

3.17 Road Surface Condition
Motorcyclists, being two-wheelers, are more susceptible to the condition of the road surface. They are more likely to skid on both dry and wet road surfaces, and in particular are put at greater risk by mud or oil on the road. Snow and ice seems to affect car drivers just as much as motorcyclists, although motorcycle use probably drops significantly when ice and snow make riding very difficult and unpleasant.

[table]
Table 13: Percentage of Vehicles Skidding by Road Surface Condition: 1999[attr colspan=”6″]
Road user Group, Dry, Wet or Flood, Snow or Ice, Mud or Oil, All Conditions
TWMV, 17.9, 26.2, 53.6, 66.4, 20.6
Cars, 10.4, 18.6, 49.5, 52.3, 14.3
All Riders & Drivers, 10.2, 18.3, 48.3, 52.0, 13.9
[/table]

3.18 Motorcyclist Casualties by Manoeuvre
As with all road user groups (except pedestrians) most motorcycle accidents are listed as “Going ahead other”. However, 13% of motorcycle accidents are listed as “Going ahead on a bend”, compared to only 8% of cars. Similarly, 12% occur when the rider is overtaking another vehicle, compared to only 4% of car accidents during this manoeuvre. This may reflect motorcyclists’ greater vulnerability during these manoeuvres.

[table delimiter=”|”]
Table 14: Motorcycle Accidents by Manoeuvre: 1999[attr colspan =”2″]
| Number
Going ahead other| 15,980
Overtaking a moving or stationary vehicle| 3,801
Going ahead on a bend| 3,582
Turning or waiting to turn right| 1,189
Waiting to go ahead| 660
Turning or waiting to turn left| 697
Stopping| 541
Changing lane| 311
Starting| 184
Parked| 60
U-Turning| 64
Reversing| 19
All known manoeuvres*| 27,122
[/table]
* Includes manoeuvre not reported

3.19 Almost one in five (18%) motorcycle accidents involve the motorcyclist losing control, without any other road user being involved. The equivalent figure for cars is 14%. However, not all loss of control accidents are due to rider error; deceptive bends, poor road surfaces and avoiding other road users also are a factor in a proportion of these accidents.

3.20 The Booth report, published in 1989, assessed nearly 10,000 motorcycle accidents in the Metropolitan Police area. It concluded that nearly two-thirds (62%) of motorcycle accidents were primarily caused by the other road user. Half of the accidents were caused by car drivers, and 10% by pedestrians. The report found that two-thirds of motorcycle accidents where the driver was at fault were due to the driver failing to anticipate the action of the motorcyclist.

3.21 In contrast, the analysis of motorcycle accidents in rural Cheshire found that 67% of motorcycle accidents were due to rider error, with losing control on a bend and overtaking featuring strongly.

3.22 Motorcyclists and Drink Driving
There is little difference in the rate of breath test failures between motorcycle riders and car drivers.

[table delimiter=”|”]
Table 15: Breath Tests: 1999[attr colspan=”6″]
Road User| No. Involved in RTA| No. Tested (%)| No. Failed| Fails as % of Involved| Fails as % of Tested
Car Drivers| 329,866| 175,916 (53%)| 6,669| 2%| 3.8%
TWMV Riders| 27,122| 12,970 (48%)| 443| 1.6%| 3.4%
[/table]

3.23 However, a lower proportion of motorcyclist fatalities (9%) were over the drink drive limit than car driver fatalities (16%). And the percentage of TWMV rider fatalities who were over the drink drive limit has fallen considerably more than the equivalent figure for drivers.

[table]
Table 16: Percentage of TWMV Riders and Motor Vehicle Driver Fatalities Over the Legal Blood Alcohol Limit: GB 1988-1999[attr colspan=”3″]
Year, ,
1988, 23, 20
1989, 21, 18
1990, 19, 18
1991, 17, 20
1992, 26, 17
1993, 15, 20
1994, 18, 22
1995, 15, 21
1996, 13, 23
1997, 13, 19
1998, 11, 17
1999 Provisional figures, 9, 20
[/table]

3.24 Motorcyclist Injury Patterns
Various studies have assessed the types and frequencies of injuries to motorcyclists. Legs are the most commonly injured, followed by the head and arms.

[table]
Table 17: Proportion of Injuries to Motorcyclists[attr colspan=”2″]
Site of Injury, % of all Injuries
Legs, 39%
Head, 23%
Arms, 19%
Shoulder/Thorax, 10%
Abdomen/Pelvis, 7%
Neck, 1%
[/table]

3.25 Around 80% of motorcyclist casualties suffer leg injuries, 56% suffer injuries to the arms and 48% to the head. However, head injuries are usually more severe than those to the legs or arms, and account for 80% of motorcyclist fatalities. Injuries to the thorax and pelvis are infrequent, but usually severe.

[table]
Table 18: Proportion of Motorcyclists by Injury[attr colspan=”2″]
Site of Injury, % of Casualties
Legs, 80%
Head, 48%
Arms, 56%
[/table]

3.26 Head Injuries
Head injuries account for 80% of motorcyclist fatalities and can include cuts and abrasions, concussion, severe facial injuries, skull fractures and injuries to the brain. They appear to be more likely in crashes in which the motorcyclist collides with another vehicle at right angles and the head impacts against the vehicle, or in cases where the rider slides along the ground and strikes their head on a kerb or piece of roadside furniture. Skull fractures may occur at speeds of 30 km/h or more, but brain injuries may happen at much lower speeds, from 11 km/h upwards.

3.27 Leg Injuries
Leg injuries account for 60% of serious injuries and may include cuts and abrasions, fractures, broken bones and dislocated joints. The knee and lower leg appear to be the most vulnerable. Leg injuries are most frequently caused in accidents which involve the motorcyclist striking the side of a vehicle at an oblique angle, or a vehicle striking the motorcyclist side-on. The injuries are caused by a direct impact or the leg being trapped and crushed between the vehicles.