CRASH MODIFICATION FACTORS CLEARINGHOUSE

Study Details

Study Title: Handbook of Road Safety Measures

Authors: Elvik, R. and Vaa, T.

Publication Date: 2004

Abstract:

Study Citation: Elvik, R. and Vaa, T., "Handbook of Road Safety Measures." Oxford, United Kingdom, Elsevier, (2004)

CMFs Associated With This Study

Category: Access management

Countermeasure: Provide a raised median

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.94	-94		All	K,A,B,C	Not specified	Rural

2.28

-128

All

O

Not specified

Rural

0.61[B]

39

All

K,A,B,C

Not Specified

Urban

0.78[B]

22

All

A,B,C

Principal Arterial Other

Urban

1.09[B]

-9

All

O

Principal Arterial Other

Urban

0.88[B]

12

All

A,B,C

Principal Arterial Other

Rural

0.82[B]

18

All

O

Principal Arterial Other

Rural

Countermeasure: Reduce driveways from 10-24 to less than 10 per mile

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.75[B]	25		All	A,B,C	Minor Arterial	Urban and suburban

Countermeasure: Reduce driveways from 26-48 to 10-24 per mile

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.69[B]	31		All	A,B,C	Minor Arterial	Urban and suburban

Countermeasure: Reduce driveways from 48 to 26-48 per mile

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.71[B]	29		All	A,B,C	Minor Arterial	Urban and suburban

Category:Advanced technology and ITS

Countermeasure: Individual changeable speed warning signs

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.59	41		All	A,B,C	Not specified	Not specified

Countermeasure: Install changeable "Queue Ahead" warning signs

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.84[B]	16		Rear end	A,B,C	Principal Arterial Other Freeways and Expressways	Urban

1.16[I]

-16

Rear end

O

Principal Arterial Other Freeways and Expressways

Urban

Countermeasure: Install changeable crash ahead warning signs

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.56[I]	44		All	A,B,C	Principal Arterial Other Freeways and Expressways	Urban

Countermeasure: Install changeable speed warning signs for individual drivers

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.54[I]	46		All	All	Not specified	Not specified

Countermeasure: Provide active close-following warning signs

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.94	6		Rear end		Not specified	Not specified

Category:Bicyclists

Countermeasure: Raised bicycle crossings

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.09	-9		Vehicle/bicycle	A,B,C	Not specified	Not specified

Category:Delineation

Countermeasure: Add lane lines on multilane roadway segments

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.82	18		All	All	Principal Arterial Other	Urban

Countermeasure: Install distance markers (angle symbols) on roadway segments

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.44	56		All	A,B,C	Principal Arterial Other Freeways and Expressways	Not specified

Countermeasure: Install edgelines, centerlines, and post-mounted delineators

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.55[B]	45		All	A,B,C	Not Specified	All

Countermeasure: Install post-mounted delineators

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.04[B*]	-4		All	A,B,C	Not Specified	Rural

1.05[B*]

-5

All

O

Not Specified

Rural

Countermeasure: Install raised pavement markers and transverse rumble strips on approach to horizontal curves

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.94	6		Run off road	A,B,C	Not specified	Rural

Countermeasure: Place centerline markings

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.99[B*]	1		All	A,B,C	Not Specified	Rural

1.01[B*]

-1

All

O

Not Specified

Rural

Countermeasure: Place edgeline and centerline markings

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.76[B]	24		All	A,B,C	Not Specified	Rural

Countermeasure: Place standard edgeline marking (4-6 in)

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.97[B*]	3		All	A,B,C	Not Specified	Rural

0.97[B*]

3

All

O

Not Specified

Rural

Countermeasure: Place wide (8 inches) edgeline markings

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.05[B*]	-5		All	A,B,C	Not Specified	Rural

0.99[I*]

1

All

O

Not Specified

Rural

Countermeasure: Placing edgelines and background/ directional markings on horizontal curves

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.81	19		Run off road	A,B,C	Not specified	Rural

Category:Highway lighting

Countermeasure: Illumination

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.69	31		All	O	Not specified	Not specified

0.31

69

All

K

All

All

0.27

74

All

K

All

Rural

0.8

20

All

A,B,C

All

Rural

0.7

30

All

O

All

Rural

0.37

64

All

K

All

Urban

0.69

32

All

A,B,C

All

Urban

0.84

16

All

O

All

Urban

0.27

73

All

K

Principal Arterial Other Freeways and Expressways

All

0.73

27

All

A,B,C

Principal Arterial Other Freeways and Expressways

All

0.68

32

All

O

Principal Arterial Other Freeways and Expressways

All

Countermeasure: Provide highway lighting

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.31	69		All	K	All	All

0.72[B]

28

Nighttime

A,B,C

All

All

0.83[B]

18

Nighttime

O

All

All

Countermeasure: Provide intersection illumination

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.62[B]	38		Nighttime	A,B,C	Not Specified	Not Specified

0.69

31

All

O

Not specified

Not specified

0.22

78

Vehicle/pedestrian

K

Not specified

Not specified

0.58[I]

42

Nighttime,Vehicle/pedestrian

A,B,C

Not Specified

Not Specified

0.23

77

All

K

Not specified

Not specified

0.5

50

All

A,B,C

Not specified

Not specified

0.52

49

All

O

Not specified

Not specified

0.19

82

Vehicle/pedestrian

K

Not specified

Not specified

0.41

59

Vehicle/pedestrian

A,B,C

Not specified

Not specified

Category:Interchange design

Countermeasure: Extend acceleration lane by approx. 98 ft (30 m)

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.89	11		All	All	Not specified	Not specified

Countermeasure: Extend deceleration lane by approx. 100 ft

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.93[B*]	7		All	All	Not Specified	Not Specified

Category:Intersection geometry

Countermeasure: Convert four-leg intersection into two three-leg intersections

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.35	-35		All	A,B,C	Not Specified	Urban

0.75[B]

25

All

A,B,C

Not Specified

Urban

0.67[B]

33

All

A,B,C

Not Specified

Urban

1.15[B]

-15

All

O

Not Specified

Urban

1[B*]

0

All

O

Not Specified

Urban

0.9[B*]

10

All

O

Not Specified

Urban

Countermeasure: Painted channelization of both major and minor roads

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.43	57		All	A,B,C	Not specified	Rural

Countermeasure: Painted channelization of left-turn lane on major road

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.78	22		All	A,B,C	Not specified	Rural

0.8

20

All

O

Not specified

Rural

1.28

-28

All

A,B,C

Not specified

Rural

0.74

26

All

O

Not specified

Rural

Countermeasure: Physical channelization of both major and minor roads

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.16	-16		All	K,A,B,C	Not specified	Rural

0.73

27

All

K,A,B,C

Not specified

Rural

0.87

13

All

O

Not specified

Rural

Countermeasure: Physical channelization of right-turn lane on major road

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.98	2		All	A,B,C	Not specified	Rural

0.87

13

All

A,B,C

Not specified

Rural

0.81

19

All

O

Not specified

Rural

Countermeasure: Provide a channelized left-turn lane on both major- and minor-road approaches

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.73[I]	27		All	A,B,C	Not Specified	Rural

Countermeasure: Provide a channelized left-turn lane on both major-road approaches

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.2	-20		All	O	Not specified	Rural

0.96[I*]

4

All

A,B,C

Not Specified

Rural

0.84

16

All

O

Not specified

Rural

Category:Intersection traffic control

Countermeasure: Permit right-turn-on-red

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.6[B]	-60		Right turn	A,B,C	Not Specified	Not Specified

1.1[B]

-10

Right turn

O

Not Specified

Not Specified

Category:On-street parking

Countermeasure: Convert angle parking to parallel parking

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.65	35		All	All	Local	Urban

0.37

63

Parking related

All

Local

Urban

Countermeasure: Convert free to regulated parking

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.94[B*]	6		All	A,B,C	Minor Arterial	Urban

1.19[B]

-19

All

O

Minor Arterial

Urban

Countermeasure: Implement time-limited parking restrictions

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.89[B]	11		All	All	Minor Arterial,Major Collector,Minor Collector	Urban

0.21[B]

79

Parking related

All

Minor Arterial,Major Collector,Minor Collector

Urban

Countermeasure: Mark parking stalls

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.51	-51		All	All	Local	Urban

2.28

-128

Parking related

All

Local

Urban

Countermeasure: Prohibit on-street parking

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.8	20		All	A,B,C	Minor Arterial	Urban

0.73

27

All

O

Minor Arterial

Urban

Countermeasure: Prohibit parking on one side of road

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.49	-49		All	A,B,C	Not specified	Urban

Category:Pedestrians

Countermeasure: Install raised pedestrian crosswalks

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.64	36		All	A,B,C	Local	Urban and Suburban

0.55

46

Vehicle/pedestrian

A,B,C

Local

Urban and Suburban

0.7

30

All

A,B,C

Local

Urban and Suburban

Countermeasure: Raised intersections

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.05	-5		All	A,B,C	Not specified	Not specified

1.13

-13

All

O

Not specified

Not specified

Countermeasure: Widen sidewalks at intersections

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.12	-12		All	A,B,C	Not specified	Not specified

Category:Railroad grade crossings

Countermeasure: Implementing signs and crossbucks at previously unprotected crossings

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.75	25		All		Not specified	Not specified

Countermeasure: Install automatic gates at crossings that previously had flashing lights and sound signals

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.55[B]	45		All	All	Not Specified	Not Specified

Countermeasure: Install automatic gates at crossings that previously had passive traffic control

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.33[B]	67		All	All	Not Specified	Not Specified

Countermeasure: Install flashing lights and sound signals

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.5[B]	50		All	All	Not Specified	Not Specified

Category:Roadside

Countermeasure: Change barrier along embankment to less rigid type

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.59[I]	41		Run off road	K	Not specified	Not specified

0.68[B]

32

Run off road

A,B,C

Not specified

Not specified

Countermeasure: Flatten sideslope from 1V:3H to 1V:4H

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.58	42		All	A,B,C	Not specified	Rural

0.71

29

All

O

Not specified

Rural

Countermeasure: Flatten sideslope from 1V:4H to 1V:6H

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.78	22		All	A,B,C	Not specified	Rural

0.76

24

All

O

Not specified

Rural

Countermeasure: Increase distance to roadside features from 16.7 ft to 30 ft

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.56[B]	44		All	All	All	Rural

Countermeasure: Increase distance to roadside features from 3.3 ft to 16.7 ft

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.78[B]	22		All	All	All	Rural

Countermeasure: Increase triangle sight distance

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.3	-30		All	A,B,C	Not specified	Not specified

1.29

-29

All

O

Not specified

Not specified

0.53

48

All

A,B,C

Not specified

Not specified

0.89

11

All

O

Not specified

Not specified

Countermeasure: Install any type of median barrier

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.57[B]	43		All	K	Principal Arterial Other	Rural

0.7[B]

30

All

A,B,C

Principal Arterial Other

Rural

1.24[B]

-24

All

All

Principal Arterial Other

Rural

Countermeasure: Install cable median barrier

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.71[B]	29		All	A,B,C	Principal Arterial Other	Rural

Countermeasure: Install concrete guardrail in median

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
1.15	-15		All	A,B,C	Principal Arterial Other	Not specified

Countermeasure: Install crash cushions at fixed roadside features

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.31[I]	69		Fixed object	K	Not Specified	Not Specified

0.31[B]

69

Fixed object

A,B,C

Not Specified

Not Specified

0.54[I]

46

Fixed object

O

Not Specified

Not Specified

Countermeasure: Install steel median barrier

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.65[B]	35		All	A,B,C	Principal Arterial Other	Rural

Countermeasure: Install wire guardrails between lanes of opposing traffic

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0	100		All	K	Principal Arterial Other	Not specified

0.74

26

All

A,B,C

Principal Arterial Other

Not specified

1.34

-34

All

All

Principal Arterial Other

Not specified

Countermeasure: New guardrail along embankment

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.56	44		Run off road	K	Not specified	Not specified

0.53

47

Run off road

A,B,C

Not specified

Not specified

0.93

7

Run off road

All

Not specified

Not specified

Category:Roadway

Countermeasure: Effects of snow fences and higher state of preparedness for the whole winter season

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.89	11		All	All	All	All

0.92

8

All

All

All

All

Countermeasure: Effects of use of salt (chemical de-icing) during the whole winter season (baseline = no salt)

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.85	15		All	A,B,C	All	All

0.92

8

All

O

All

All

1.12

-12

All

A,B,C

All

All

1

0

All

O

All

All

Countermeasure: Raise standard by one class for winter maintenance

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.89[B]	11		All	A,B,C	All	All

0.73[B]

27

All

O

All

All

Countermeasure: Short-term effects of all measures to control snow, slush or ice

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.5	50		All		All	All

0.71

29

All

All

All

0.96

5

All

All

All

Category:Signs

Countermeasure: Advance static curve warning signs

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.7	30		All	A,B,C	Not specified	Not specified

0.92

8

All

O

Not specified

Not specified

Countermeasure: Install combination horizontal alignment/ advisory speed signs

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.87[B]	13		All	A,B,C	Not Specified	Not Specified

0.71[I]

29

All

O

Not Specified

Not Specified

Countermeasure: Install signs to conform to MUTCD

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.85	15		All	A,B,C	Local	Urban

0.93

7

All

O

Local

Urban

Category:Speed management

Countermeasure: Adjacent to roads with speed humps

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.95[B*]	5		All	A,B,C	Local	Urban and Suburban

Countermeasure: Area-wide or corridor-specific traffic calming

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.89[B]	11		All	A,B,C	All	Urban

0.82[B]

18

All

A,B,C

Local

Urban

0.94[B*]

6

All

A,B,C

Major Collector,Minor Collector

Urban

0.95[I*]

5

All

O

All

Urban

0.94[B*]

6

All

O

Local

Urban

0.97[I*]

3

All

O

Major Collector,Minor Collector

Urban

Countermeasure: Install speed humps

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.6[I]	40		All	A,B,C	Local	Urban and Suburban

0.5

50

All

A,B,C

Local

Urban and Suburban

Countermeasure: Install transverse rumble strips as traffic calming device

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.66	34		All	All	Local	Urban and Suburban

0.64

36

All

A,B,C

Local

Urban and Suburban

0.73

28

All

O

Local

Urban and Suburban

Countermeasure: Traffic calming

CMF	CRF(%)	Quality	Crash Type	Crash Severity	Roadway Type	Area Type
0.68	32		All	All	Minor Collector	Urban

0.67

33

All

A,B,C

Minor Collector

Urban

0.75

25

All

O

Minor Collector

Urban

0.67

33

All

A,B,C

Minor Collector

Urban

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