Road Risk

In Kent

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WELCOME

Welcome to the SIGNPOST SERIES, a suite of reports to support professionals working in Road Safety. Designed

by Road Safety Analysis, these profiles provide an authoritative overview of performance that can assist in

directing investment and effort to reduce casualties on the roads.

For more information on other services offered by Road Safety Analysis, please visit

www.roadsafetyanalysis.co.uk

Contents

Welcome .................................................................................................................................................................. 2

Introduction ............................................................................................................................................................. 3

Overview of Kent ..................................................................................................................................................... 3

Overall road risk ....................................................................................................................................................... 4

Crashes of all severities ........................................................................................................................................ 4

Fatal or serious injury crashes ............................................................................................................................. 4

Progress in reducing road risk .............................................................................................................................. 4

Road risk for pedestrians and pedal cyclists ............................................................................................................ 5

Pedestrian road risk ............................................................................................................................................. 5

Pedestrian risk on all roads .............................................................................................................................. 5

Pedestrian risk on urban roads ........................................................................................................................ 5

Pedal cycle road risk............................................................................................................................................. 6

Pedal cycle risk on urban roads ....................................................................................................................... 6

Road risk for vulnerable motor vehicle users .......................................................................................................... 7

Motorcycle user road risk .................................................................................................................................... 7

Motorcycle road risk ........................................................................................................................................ 7

Moped road risk ............................................................................................................................................... 7

Young driver involvement road risk ..................................................................................................................... 7

Appendix .................................................................................................................................................................. 9

Data sources......................................................................................................................................................... 9

Highway Authority Network Classification System .............................................................................................. 9

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SIGNPOSTS IN ROAD SAFETY 2013: RISK OF

CRASHES ON ROADS IN KENT

BY ROAD SAFETY ANALYSIS

INTRODUCTION

The SIGNPOST SERIES are road safety profile documents which provide comprehensive insight into risk faced by

local communities. Each profile examines either road risk on the network of a specific highway authority, or

risk experienced by the residents of a particular local authority district area. This profile examines risk of

crashes on Kent’s road network.

All crash, vehicle, driver and casualty information in this document is derived from national STATS19 data for a

six year period from 2007 to 2012. The figures in this profile refer to crashes recorded within the boundaries of

the Kent council area. The STATS19 dataset is available to the road safety community for detailed analysis in

MAST Online. A less detailed version can be downloaded as a raw dataset from HM Government's transparency

website at data.gov.uk.

This profile examines crashes on Kent’s roads, rather than the individual casualties and drivers who were

involved in them. This approach is the most suitable method of assessing risk on a road network, because the

overall circumstances of each incident are more likely to be relevant to its safety performance than personal

factors. Risk profiling for individuals is examined in separate profile documents in the SIGNPOST SERIES, since it is

more appropriate to examine the 'people' aspect of risk on the basis of residency rather than crash location.

OVERVIEW OF KENT

The English County council area of Kent (ONS code E10000016) covers an area of 1363.9 square miles approx

and had a total population of 1,463,740 residents approx based on 2011 mid-year estimates. With 1,073

residents per square mile it falls in the 7th decile of national population density, lying 132nd out of 205

highway authority areas.

As a county authority, Kent consists of 12 separate local authority districts. SIGNPOST SERIES profiles which

assess resident casualty risk on the basis of district residency are available separately.

Based on statistics produced by the Department for Transport in 2011, the total length of roads in Kent was

5,646.1 miles. This places it in the 1st decile of absolute road length, lying 4th out of 205 highway authority

areas. 1,840.2 miles of the network (33%) consists of non-motorway urban roads, placing the authority in the

8th decile of urban roads extent with a ranking of 148th out of 205 highway authority areas.

Kent had an average annual traffic flow of 8,885.67 million motor vehicle miles per year over the period 2007

to 2012. This places it in the 1st decile of absolute traffic flow, lying 2nd out of 205 highway authority areas.

The area’s average traffic density per mile of road is around 4,309 motor vehicles per day, placing it in the 5th

decile of relative traffic density with a ranking of 99th out of 205 highway authorities.

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OVERALL ROAD RISK

This section calculates risk based on all reported crashes on the roads of Kent over the six year period 2007 to

2012, regardless of age, residency or road user type of the casualties and drivers involved. It is likely that

additional unreported crashes occurred, but no estimate of these can be included in this report. Crash figures

in this section are also indexed and ranked relative to overall traffic flow, expressed as the average number of

million motor vehicle miles travelled per reported crash. Kent’s overall risk and progress in comparison to other

similar areas is illustrated in Chart B.

Crashes of all severities

On average, approximately 4,419 crashes per year are reported on Kent’s roads. These figures include crashes

resulting only in slight injuries such as minor cuts, bruises, shock and whiplash. Kent’s overall road risk rate

relative to traffic is 2.01 million mv miles per crash. In comparison, the national rate is 1.90 million mv miles

per crash.

Consequently, Kent’s national road risk index is 95, where a value of 100 represents the national rate. This

means that road risk on Kent's roads is 5% lower than the national average. Kent has a national road risk

ranking of 110th (where first place indicates the highest risk), placing it in the 6th decile of road risk across 205

highway authorities in Britain.

Fatal or serious injury crashes

On average, approximately 516 crashes per year resulting in fatal or serious injury are reported on Kent’s

roads. This figure includes an average of 57.0 crashes per year resulting in one or more fatalities, but excludes

crashes resulting in slight injuries only. Kent’s fatal and serious road risk rate relative to traffic is 17.21 million

mv miles per crash. In comparison, the national rate is 12.80 million mv miles per crash.

Consequently, Kent’s national fatal and serious road risk index is 74, where a value of 100 represents the

national rate. This means that fatal and serious road risk on Kent’s roads is 26% lower than the national

average. Kent has a national fatal and serious road risk ranking of 163rd (where first place indicates the highest

risk), placing it in the 8th decile across 205 highway authorities in Britain.

Progress in reducing road risk

These statistics measure the change in road risk over time on Kent’s roads. A local trend is established by

comparing a baseline period (2007 to 2009) to the most recent information available (2010 to 2012). Progress

is assessed by evaluating this trend relative to nationwide change over the same period. A comparison of

recent progress to overall risk is illustrated in Chart A.

The average number of crashes reported on Kent’s roads has changed by -403 crashes per year over three

years. This includes a change of -87 crashes per year over three years which resulted in fatal or serious injuries.

Kent has a road risk progress index of 104, where a value of 100 represents the national rate of progress and

higher values indicate less progress. The corresponding fatal and serious road risk progress index is 96. This

means that progress in improving Kent’s road risk is 4% slower than the national rate over the last three

years, while progress in improving fatal and serious road risk is 4% faster than the national rate.

Kent’s national road risk progress ranking is 144th (where first place indicates the best progress), placing it in

the 7th decile across 205 highway authorities in Britain. The corresponding fatal and serious road risk progress

ranking is 90th, placing it in the 5th decile of progress.

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ROAD RISK FOR PEDESTRIANS AND PEDAL CYCLISTS

This section assesses the risk of crashes involving injury to vulnerable road users without motor vehicles. The

scope of this section covers all crashes involving injury to such road users on Kent’s roads over the six year

period 2007 to 2012. It is likely that additional unreported crashes occurred. Crash figures in this section are

also indexed and ranked relative to road network length, expressed as miles of road per reported crash. Since

motorway regulations do not permit pedestrians and non motor vehicles, motorway crashes have been

omitted from this analysis and motorways have been excluded from network length calculations. Progress

indices and rankings are only available in categories where sample sizes are generally large enough for results

to be meaningful.

Pedestrian road risk

Pedestrian risk on all roads

On average, there are approximately 614.8 crashes per year on the roads of Kent which result in at least one

pedestrian casualty. This equates to an annual rate of 9.0 miles of road per crash in the area. In comparison,

the national pedestrian crash rate is 9.3 miles of British road per crash each year. This calculation completely

excludes motorways (both crashes and road miles) but includes all other urban and rural roads.

Consequently, Kent’s pedestrian road risk index is 103, where a value of 100 represents the national rate. This

means that pedestrian road risk in Kent is 3% higher than the national average. The authority has a national

pedestrian road risk ranking of 116th (where first place indicates the highest risk), placing it in the 6th decile of

pedestrian road risk across 205 highway authorities in Britain.

The average number of crashes resulting in pedestrian injury has changed by -6 crashes per year over three

years (excluding motorways). Kent has a pedestrian road risk progress index of 112, where a value of 100

represents the national rate of progress and higher values indicate less progress. This means that progress in

improving pedestrian road risk in Kent is 12% slower than the national rate over the last three years. Kent’s

national pedestrian road risk progress ranking is 161st (where first place indicates the best progress), placing it

in the 8th decile of progress across 205 highway authorities in Britain. A comparison of pedestrian progress to

overall pedestrian risk is illustrated in Chart A.

Pedestrian risk on urban roads

On average, there are approximately 486.5 crashes per year on urban roads in Kent which result in at least

one pedestrian casualty. This equates to an annual rate of 3.0 miles of urban road per crash in the area. In

comparison the national pedestrian crash rate is 3.4 miles of British urban road per crash each year. This

calculation completely excludes all rural roads and motorways (in terms of both crashes and road miles).

Consequently, Kent’s urban pedestrian road risk index is 113, where a value of 100 represents the national

rate. This means that urban pedestrian road risk in Kent is 13% higher than the national average. The

authority has a national urban pedestrian road risk ranking of 66th (where first place indicates the highest risk),

placing it in the 4th decile of urban pedestrian road risk across 205 highway authorities in Britain.

The average number of crashes resulting in pedestrian injury has changed by -16 crashes per year over three

years (urban roads excluding motorways). Kent has an urban pedestrian road risk progress index of 110,

where a value of 100 represents the national rate of progress and higher values indicate less progress. This

means that progress in improving urban pedestrian road risk in Kent is 10% slower than the national rate

over the last three years. Kent’s national urban pedestrian road risk progress ranking is 138th (where first place

indicates the best progress), placing it in the 7th decile of progress across 205 highway authorities in Britain. A

comparison of urban pedestrian progress to overall urban pedestrian risk is illustrated in Chart A.

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Pedal cycle road risk

On average, there are approximately 328.5 crashes per year on the roads of Kent which involve at least one

pedal cycle. These figures include injury crashes involving a pedal cycle but not necessarily where a pedal cycle

rider or pillion passenger was injured. This equates to an annual rate of 16.9 miles of road per crash in the

area. In comparison, the national pedal cycle crash rate is 13.6 miles of British road per crash each year. This

calculation completely excludes motorways (both crashes and road miles) but includes all other urban and rural

roads.

Consequently, Kent’s pedal cycle road risk index is 81, where a value of 100 represents the national rate. This

means that pedal cycle road risk in Kent is 19% lower than the national average. The authority has a national

pedal cycle road risk ranking of 124th, (where first place indicates the highest risk), placing it in the 7th decile

of pedal cycle road risk across 205 highway authorities in Britain.

Pedal cycle risk on urban roads

On average, there are approximately 223.5 crashes per year on urban roads in Kent which involve at least

one pedal cycle. This equates to an annual rate of 5.6 miles of urban road per crash in the area. In

comparison, the national pedal cycle crash rate is 5.0 miles of British urban road per crash per year. This

calculation completely excludes all rural roads and motorways (in terms of both crashes and road miles).

Consequently, Kent’s urban pedal cycle road risk index is 88, where a value of 100 represents the national rate.

This means that urban pedal cycle road risk in Kent is 12% lower than the national average. The authority has

a national urban pedal cycle road risk ranking of 85th (where first place indicates the highest risk), placing it in

the 5th decile of urban pedal cycle road risk across 205 highway authorities in Britain.

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ROAD RISK FOR VULNERABLE MOTOR VEHICLE USERS

This section assesses road risk for motor vehicle users who may be among the most vulnerable to injury or

crash involvement. The scope of this section covers all reported crashes involving selected road user types on

Kent’s roads over the six year period 2007 to 2012. It is likely that additional unreported crashes occurred.

Crash figures in this section are also indexed and ranked relative to overall traffic flow, expressed as the

average number of million motor vehicle miles travelled per reported crash. Progress indices and rankings are

only available in categories where sample sizes are generally large enough for results to be meaningful. A

comparison of risk between different road user groups is illustrated in Chart A.

Motorcycle user road risk

In order to improve insight into local issues and priorities, motorcycle user road risk has been split into two

categories for separate analysis. For the purpose of this report, motorcycles include all powered two wheeled

vehicles with a reported engine capacity of 50 cc and over. Mopeds are two wheeled vehicles with a reported

engine capacity of under 50cc. Figures include all crashes involving one or more motorcycle or moped where

there was an injury but not necessarily to the rider or pillion passenger of the motorcycle or moped.

Motorcycle road risk

On average, there are approximately 454.5 crashes per year on the roads of Kent which involve at least one

motorcycle with an engine size of 50cc and over. This equates to an annual rate of 19.55 million mv miles per

crash. In comparison, the national motorcycle crash rate is 17.68 million mv miles per crash. Consequently,

Kent’s motorcycle road risk index is 90, where a value of 100 represents the national rate. This means that

motorcycle road risk in Kent is 10% lower than the national average. The authority has a national motorcycle

road risk ranking of 86th (where first place indicates the highest risk), placing it in the 5th decile of large

motorcycle road risk across 205 highway authorities in Britain.

Moped road risk

On average, there are approximately 118.3 crashes per year on the roads of Kent which involve at least one

moped. This equates to an annual rate of 75.09 million mv miles per crash. In comparison, the national moped

crash rate is 86.20 million mv miles per crash. Consequently, Kent’s moped road risk index is 115, where a value

of 100 represents the national rate. This means that moped road risk in Kent is 15% higher than the national

average. The authority has a national moped road risk ranking of 72nd (where first place indicates the highest

risk), placing it in the 4th decile of moped road risk across 205 highway authorities in Britain.

Young driver involvement road risk

This section examines all reported crashes on Kent’s roads involving young adult drivers, regardless of personal

injury. This approach is used to scrutinise the exposure of younger drivers to road risk. All analysis within this

section excludes riders of pedal cycles, motorcycles and mopeds, since risk for these road user groups has been

considered separately. For the purposes of this analysis, young adults are all persons aged between 17 and 24

inclusive.

On average, there are approximately 1263.7 crashes per year on the roads of Kent which involve at least one

young adult driver. This equates to an annual rate of 7.03 million mv miles per crash. In comparison, the

national young driver involvement crash rate is 7.48 million mv miles per crash. Consequently, Kent’s young

driver involvement road risk index is 106, where a value of 100 represents the national rate. This means that

young driver involvement road risk in Kent is 6% higher than the national average. The authority has a

national young driver involvement road risk ranking of 97th (where first place indicates the highest risk),

placing it in the 5th decile of young driver involvement road risk across 205 highway authorities in Britain.

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The average number of crashes involving young adult drivers has changed by -201 crashes per year over

three years (excludes pedal cycles, motorcycles and mopeds). Kent has a young driver involvement road risk

progress index of 110, where a value of 100 represents the national rate of progress and higher values indicate

less progress. This means that progress in improving young driver involvement road risk in Kent is 10% slower

than the national rate over the last three years. Kent’s national young driver involvement road risk progress

ranking is 166th (where first place indicates the best progress), placing it in the 9th decile of progress across

205 highway authorities in Britain. A comparison of young driver involvement progress to overall young driver

involvement risk is illustrated in Chart A.

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APPENDIX

Data sources

Reported road casualties by residency: MAST Online

http://www.roadsafetyanalysis.org/mast-online/

Subset of raw STATS19 dataset released by HM Government: Data.gov.uk

http://data.gov.uk/dataset/road-accidents-safety-data

Motor vehicle traffic by Local Authority: Department for Transport

http://www.dft.gov.uk/statistics/tables/tra8901/

Road lengths by Local Authority: Department for Transport

http://www.dft.gov.uk/statistics?post_type=release&series=road-lengths-series

Population and area in England and Wales: Office for National Statistics

http://www.ons.gov.uk/ons/taxonomy/index.html?nscl=Population+Estimates

Population and area in Scotland: General Register Office for Scotland

http://www.gro-scotland.gov.uk/statistics/theme/population/estimates/mid-year/index.html

Highway Authority Network Classification System

As mentioned in the National Signpost Report 2013, there appears to be a problem with comparing authorities

nationally using the road risk measurement. The trend is for authorities with very dense networks and very

high traffic flows to have much higher road risk indexes. This flaw applies equally to the DfT measures used in

the Outcome Indicators section of the Strategic Framework which are essentially the same but expressed as a

rate, rather than as an index. This makes meaningful local comparison impossible unless you are able to

instead compare similar authorities.

In order to allow fairer comparison between authorities, RSA have devised a classification system based on the

network density and proportion of urban roads in each highway authority. This allows highway authorities to

compare their performance to areas with similar road network characteristics. Chart B shows Kent’s

performance and progress in relation to authorities which have similar road network characteristics.

There are five groups which are defined as:

Class Class Description

1 Super densely networked, super urban London Boroughs

2 Very densely networked, very urban authorities including some relatively less densely populated London Boroughs

3 Densely networked urban areas

4 Less densely networked, less urban authorities

5 Mostly rural authorities with lower road network densities

95 74

103 113

81 88 90

115 106

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Chart A - Kent Road Risk and Progress Indices (2007-2012)

KSI CrashesAll

Crashes

Urban Pedestrian

CrashesPedestrian

Crashes

Pedal Cycle Crashes

MC Crashes

Moped Crashes

Young Adult Crashes

Urban Pedal Cycle

Crashes

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All Resident Casualties Index

Chart B - Performance and Progress in Kent - HANC Group 4

Kent

High risk, more improvement

Low risk, more improvement

Low risk, less improvement

High risk, less improvement