Definitions of Bicycle Crash Types

Possible Cause/Problem #1

Motorist fails to stop at a stop sign or yield at a yield sign or uncontrolled intersection. The motorist could be speeding or otherwise fail to observe correct right-of-way, including flagrantly violating sign control.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Reduce number of lanes (9).
3. Reduce lane width (10).
4. Reduce curb radii to slow motor vehicle turning speeds (16).
5. Install roundabout (17).
6. Add/improve intersection markings (18).
7. Improve intersection sight distance (19).
8. Redesign merge area (21).
9. Install mini traffic circle at intersection (25).
10. Add chicanes or other traffic calming to reduce vehicle speeds (26, 27).
11. Provide raised intersection and other traffic calming treatments (30).
12. Provide path intersection treatments for shared-use paths crossing the roadway (32).
13. Provide path intersection warnings/advance treatments for shared-use paths crossing the roadway (33).
14. Install traffic signal (35). If signal is installed, add bike detection/activation (36).
15. Make sign improvements (37).
16. Improve pavement markings (38).
17. Make school zone improvements (39).
18. Provide law enforcement (40).
19. Provide bicyclist education on wrong-way riding and riding on the sidewalk (41).
20. Provide motorist education (42).

Possible Cause/Problem #2

The motorist pulls out into the path of a bicyclist traveling through the intersection after first stopping (or slowing). The bicyclist could be riding the wrong way or on the sidewalk or both and ride into the intersection in the pedestrian crosswalk area. The motorist may pull out and fail to check or notice the bicyclist approaching (particularly from the right). The motorist may be turning right.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Reduce curb radii to slow turning speeds (16).
3. Install roundabout (17).
4. Add/improve intersection markings (18).
5. Improve sight distance (19).
6. Install mini traffic circle (25).
7. Provide raised intersection (30).
8. Provide path intersection treatments for shared-use paths crossing the roadway (32).
9. Provide trail intersection warnings/advance treatments for shared-use paths adjacent to the roadway (33).
10. Make school zone improvements (39).
11. Provide bicyclist education (41).
12. Provide motorist education (42).

Possible Cause/Problem #1

The bicyclist rides into the intersection through a red signal without stopping. The bicyclist may be trying to rush through on an amber signal indication, fail to see the red signal, or choose to disregard the signal. The bicyclist may not want to interrupt momentum or stop for a signal with an excessively long delay or that does not detect bicyclists’ presence. Inexperience could also contribute to this type of crash. The signal may be more difficult to observe if the bicyclist is traveling wrong-way or riding on the sidewalk.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Install roundabout (17).
3. Add/improve intersection markings (18).
4. Improve sight distance (19).
5. Provide path intersection treatments for shared-use paths crossing the roadway (32).
6. Provide path intersection advance warning treatments for shared-use paths crossing the roadway (33).
7. Install/optimize signal timing (35).
8. Install bike-activated signals (36).
9. Make sign improvements (37).
10. Improve pavement markings (38).
11. Make school zone improvements (39).
12. Provide law enforcement (40).
13. Provide bicyclist education (41).

Possible Cause/Problem #2

The bicyclist enters the intersection on a green or amber traffic signal indication but fails to clear the intersection when the traffic signal changes to green for the cross-street traffic. A multiple threat crash can also occur when the signal changes to green for the cross-street traffic and the bicyclist is struck by a motor vehicle whose view was obstructed by standing or stopped traffic in an adjacent lane.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Reduce the number of traffic lanes (9).
3. Reduce the width of traffic lanes (10).
4. Install roundabout (17).
5. Add/improve intersection markings (18).
6. Improve sight distance at the intersection (19).
7. Add traffic calming treatments to slow motor vehicle speed (25, 26, 27, and 30).
8. Provide path intersection treatments for shared-use paths crossing the roadway (32).
9. Provide path intersection warnings/advance treatments for shared-use paths crossing the roadway (33).
10. Optimize signal timing (35).
11. Install bike-activated signal (36).
12. Make school zone improvements (39).
13. Provide bicyclist education (41).
14. Provide motorist education about multiple threat (42).

Possible Cause/Problem #3

The bicyclist rides into the intersection after stopping for a red signal and into the path of a motorist. The bicyclist may ride out after waiting for a green indication if there is no provision for bicycle detection or the delay is excessive.

General Countermeasures

1. Install a modern roundabout (17) or mini traffic circle (25) (depending on street function and volumes).
2. Improve signal timing (35).
3. Add bike-activation to the traffic signal (36).
4. Enforce traffic laws (40).
5. Provide bicyclist education (41).

Possible Cause/Problem #1

Bicyclist fails to yield at a stop sign, yield sign or uncontrolled intersection. Sidewalk or wrong-way riding may exacerbate the problem by increasing the chances the bicyclist will not notice and obey sign control. Younger bicyclists tend to be disproportionately involved in this crash type.

General Countermeasures

1. Add/improve lighting (4).
2. Install roundabouts (17).
3. Improve sight distance at intersection (19).
4. Install mini traffic circle (25).
5. Provide path intersection treatments (32).
6. Provide path intersection warnings/advance treatments (33).
7. Install traffic signal (35) and bike-activated signal (36).
8. Make sign improvements (37).
9. Improve pavement markings (38).
10. Make school zone improvements (39).
11. Provide law enforcement (40).
12. Provide bicyclist education (41).

Possible Cause/Problem #2

The bicyclist rides out after stopping (or slowing). At a yield or two-way stop, the motorist could be speeding, the bicyclist may underestimate the time needed to start-up and get through the intersection, or the bicyclist may not detect an approaching motorist. At a four-way stop, the bicyclist may not understand right-of-way rules. A multiple threat situation can also occur at a non-signalized location.

General Countermeasures

1. Add/improve lighting (4).
2. Reduce the number of traffic lanes (9).
3. Recuce the width of traffic areas (10).
4. Install roundabout (17).
5. Implement special intersection markings (18).
6. Improve sight distance at the intersection (19).
7. Redesign merge area (21).
8. Install mini traffic circle (25).
9. Install chicanes or other traffic calming measures to slow motorist speeds (26, 27, 30).
10. Install speed tables, humps, or cushions (27).
11. Install raised intersection (30).
12. Install traffic signal (35) and bike-activated signal (36).
13. Provide bicyclist education (41).
14. Provide motorists education about multiple threat and child bicyclists (42).

Possible Cause/Problem

The motorist pulls out of a residential or commercial driveway or alleyway and fails to yield to a bicyclist riding along the roadway, on the sidewalk, or on a parallel shared-use path. Visibility may be obscured by buildings, parked cars, trees and shrubs, signal control boxes, sign posts and a host of other things that can be found along the sidewalk or edge of the roadway. The motorist may also fail to look right before pulling out or fail to detect higher-speed bicyclists or those traveling wrong-way on the roadway or sidewalk.

General Countermeasures

1. Make parking improvements to increase sight distance (5).
2. Make driveway improvements (7).
3. Improve access management (8).
4. Provide path intersection treatments for shared-use paths adjacent to the roadway (32).
5. Provide path intersection warning treatments for shared-use paths adjacent to the roadway.
6. Optimize signal timing to create gaps mid-block (35).
7. Make sign improvements (37).
8. Improve pavement markings (38).
9. Provide law enforcement (40).
10. Provide bicyclist education (41).
11. Provide motorist education (42).

Possible Cause/Problem

The bicyclist rides out from a residential driveway, commercial driveway, sidewalk, or other midblock location into the road without stopping or yielding and is struck by a motorist. This crash type is a common one for young children who fail to stop and scan for vehicles before crossing the road or pulling out into traffic. Motorists speeding through neighborhood streets increase the risk of being unable to avoid this type of crash, so traffic calming measures may be appropriate.

General Countermeasures

1. Make parking improvements to increase visibility (5).
2. Install medians or crossing islands (6).
3. Make driveway improvements (7).
4. Improve access management (8).
5. Reduce number of lanes (9).
6. Reduce lane width (10).
7. Install traffic calming measures (26, 27, 28, 29).
8. Provide path intersection treatments for midblock roadway crossings (32).
9. Provide path intersection advance warnings treatments (33).
10. Optimize signal timing to create gaps mid-block (35).
11. If midblock signal is installed, add bike detection or activated signal (36).
12. Provide school zone improvements (39).
13. Provide law enforcement (40).
14. Provide bicyclist education (41).

Possible Cause/Problem #1

The motorist turns left into the path of an oncoming bicyclist. The problem frequently occurs at signalized intersections on roads with four or more lanes, but may occur at driveways and other non-signalized junctions. The left-turning motorist is waiting for a gap in oncoming traffic and fails to look for, see, or yield to the oncoming bicyclist.

Possible Cause/Problem #2

A motorist turns or merges left across the path of a bicyclist who is traveling straight ahead in the same direction as the motorist. Many times this crash occurs at an intersection or driveway where the bicyclist is riding the wrong way against traffic or is riding the wrong way against traffic on the sidewalk. Reducing wrong-way riding would be a goal of bicyclist education and other countermeasures.

Most general countermeasures are the same for these first two types of crashes.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Install medians or crossing islands (6).
3. Make driveway improvements (7).
4. Improve access management (8).
5. Provide bike lanes (11).
6. Provide paved shoulders (13).
7. Reduce curb radii or redesign skewed intersections (16).
8. Install roundabout (17).
9. Enhance intersection markings (18).
10. Make sight distance improvements at intersection (19).
11. Restrict left turns (20).
12. Implement mini traffic circle (25).
13. Install traffic diversion (29).
14. Install raised intersection (30).
15. Provide path intersection treatments for shared-use paths adjacent to the roadway (32).
16. Provide path intersection warnings/advance treatments for shared-use paths adjacent to the roadway (33).
17. Install or optimize signal timing (dedicated left turn) (35).
18. Add sign improvements (37).
19. Provide bicyclist education (41).
20. Provide motorist education (42).

Possible Cause/Problem #3

A motorist merges left across the path of a bicyclist traveling straight ahead at an on/off ramp or other merge or weave area.

General Countermeasures

1. Improve roadway lighting (4).
2. Enhance intersection markings (18) or make pavement marking improvements (38).
3. Add sign improvements (37).
4. Redesign merge area (21).

Possible Cause/Problem #4

A motorist, bus, or delivery vehicle strikes a bicyclist when pulling out of a parking space or stop.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Provide parking treatments (5).
3. Provide transit stop treatments (covered under bike lanes) (11).
4. Provide combination lanes (14).
5. Provide bicyclist education (41).
6. Provide motorist education (42).

Possible Cause/Problem #1

At an intersection, merge area, or driveway, the motorist turns or merges right across the path of a bicyclist who is traveling straight ahead in the same direction. The motorist may misjudge the speed of the bicyclist or believe (mistakenly) that the bicyclist should wait for them.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Provide parking treatments (5).
3. Make driveway improvements (7).
4. Improve access management (8).
5. Reduce number of travel lanes to slow motor vehicle speeds (9).
6. Reduce lane width to encourage bicyclists to take the lane (in low-speed areas) (10).
7. Provide bike lanes (11).
8. Provide paved shoulders (13).
9. Reduce curb radii (16).
10. Improve intersection markings (18).
11. Implement turning restrictions (20).
12. Redesign merge areas (21).
13. Install traffic diversion (29).
14. Add raised intersection (30).
15. Provide path intersection treatments for shared-use paths adjacent to the roadway (32).
16. Provide path intersection warnings/advance treatments for shared-use paths adjacent to the roadway (33).
17. Make sign improvements (37).
18. Improve pavement markings (38).
19. Provide law enforcement (40).
20. Provide bicyclist education (41).
21. Provide motorist education (42).

Possible Cause/Problem #2

A motorist turns right, striking a bicyclist approaching from the opposite direction. The bicyclist is most likely riding the wrong way, against traffic, but could be legally riding on the sidewalk or an adjacent shared-use path. This crash may involve a right-turn-on-red, with the bicyclist possibly violating a red signal since the crash type involves traveling on a parallel path to the motorist.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Make driveway improvements (7).
3. Implement turning restrictions (20).
4. Install traffic diversion (29).
5. Provide path intersection treatments for shared-use paths adjacent to the roadway (32).
6. Provide path advance of intersection warning treatments for shared-use paths adjacent to the roadway (33).
7. Make sign improvements (37).
8. Provide bicyclist education (41).
9. Provide motorist education (42).

Possible Cause/Problem #3

A motorist, bus, or delivery vehicle strikes a bicyclist when pulling into a parking space or stop.

General Countermeasures

1. Add/improve roadway lighting (4).
2. Provide parking treatments (5).
3. Provide transit stop treatments (covered under bike lanes) (11).
4. Provide combination lanes (14).
5. Provide bicyclist education (41).
6. Provide motorist education (42).

Possible Cause/Problem #1

The bicyclist turns or merges left from the right side of the roadway. The rider fails to see or yield to a motorist coming from behind and is hit by the overtaking motorist. The crash also could involve a bicyclist riding out from a sidewalk or path beside the road. Speed of overtaking vehicles may be a factor in this group of crashes. The motorist also may not see the bicyclist, or may not suspect that the bicyclist will turn in front in time to react.

General Countermeasures

1. Make roadway surface hazard improvements (1).
2. Add/improve roadway lighting (4).
3. Provide parking improvements (5).
4. Reduce number of lanes/road diet (9).
5. Reduce lane width in low-speed areas to encourage shared-lane use (10).
6. Install roundabout (17).
7. Improve intersection markings (18).
8. Perform repetitive and short-term maintenance to reduce surface hazards (22).
9. Perform major maintenance (23).
10. Institute a hazard identification program (24).
11. Install mini traffic circle (25).
12. Provide traffic calming treatments (26, 27, 28) to slow motor vehicle speeds.
13. Divert traffic (29).
14. Install raised intersection (30).
15. Provide path intersection treatments (parallel paths adjacent to the roadway) (32).
16. Provide path intersection warnings/advance treatments (33).
17. Make pavement marking improvements (38).
18. Provide bicyclist education (41).

Possible Cause/Problem #2

The bicyclist attempts to make a left turn and rides into the path of an oncoming motorist. The crash could occur at an intersection, a midblock driveway,. or a shared-use path.

General Countermeasures

1. Install medians or crossing islands (6).
2. Improve driveways (7).
3. Improve access management (8).
4. Reduce number of lanes/road diet (9).
5. Reduce lane width (10).
6. Install roundabout (17).
7. Improve intersection markings (18).
8. Improve sight distance (19).
9. Install mini traffic circle (25).
10. Provide trail intersection treatments (32).
11. Provide trail intersection warnings/advance treatments (33).
12. Install/optimize signal timing (35).
13. Add bike activated signals (36).
14. Make pavement marking improvements (38).
15. Provide bicyclist education (41).

Possible Cause/Problem #1

The bicyclist turns or merges right into the path of an oncoming motorist. The crash could occur at an intersection or mid-block. The bicyclist may be riding out from an adjacent sidewalk or shared-use path or attempting to make a right turn from the wrong side of the roadway.

General Countermeasures

1. Reduce number of lanes/road diet to gain space for bike lanes (9).
2. Reduce lane width (10).
3. Install bike lanes on both sides of the street (11).
4. Provide/improve intersection markings (18).
5. Perform repetitive and short-term maintenance (22).
6. Perform major maintenance (23).
7. Institute a hazard identification program (24).
8. Add traffic calming treatments to slow motorist speeds (25, 26, 27, 28, 29, 30).
9. Provide path intersection treatments for shared-use paths adjacent to the roadway (32).
10. Provide path intersection warnings/advance treatments for shared-use paths adjacent to the roadway (33).
11. Make pavement marking improvements (38).
12. Provide bicyclist education on wrong-way riding (41).

Possible Cause/Problem #2

The bicyclist turns or merges right into the path of a motorist who is traveling straight ahead in the same original direction as the bicyclist. The bicyclist may be attempting to change lanes to make a right turn. This crash can also involve a bicyclist riding out from a sidewalk or shared-use path beside the road or changing from traveling facing traffic (wrong side of the street) to the correct side of the street.

General Countermeasures

1. Reduce number of lanes/road diet to gain space for bike lanes (9).
2. Reduce lane width to slow motor vehicle speeds (10).
3. Install bike lanes on both sides of the street (11).
4. Provide or improve intersection markings (18).
5. Institute good maintenance practices to reduce surface and other hazards (22, 23, 24).
6. Add traffic calming treatments (25, 26, 27, 28, 29, 30).
7. Provide trail intersection treatments for shared-use paths adjacent to the roadway (32).
8. Provide trail intersection warnings/advance treatments for shared-use paths adjacent to the roadway (33).
9. Make pavement marking improvements (38).
10. Provide bicyclist education on wrong-way riding and scanning behind (41).

Possible Cause/Problem #1

The motorist is overtaking and fails to detect a bicyclist, striking the bicyclist from behind. These crashes often occur at night, and one or both parties may have been drinking. The bicyclist may have inadequate lights or reflectors, or may not be using lights.

General Countermeasures

1. Provide space on bridges/overpasses (2).
2. Provide space and other measures in tunnels/underpasses (3).
3. Add/improve roadway lighting (4).
4. Provide space on roadway for bicyclists with bike lanes (11), wide curb lanes (12), paved shoulders (13), or combination lanes (14).
5. Provide chicanes or serpentine for low-speed, shared-lane situations (26).
6. Provide other traffic calming measures (27, 28, 29).
7. Provide a separate path or trail (31).
8. Make sign improvements (37).
9. Improve pavement markings (38).
10. Provide bicyclist education about conspicuity and riding at night (41).
11. Provide motorist education (42).

Possible Cause/Problem #2

The overtaking motorist strikes a bicyclist suddenly swerving to the left, possibly to avoid an object or surface irregularity, extended door of a parked car, or other obstacle.

General Countermeasures

1. Make roadway surface hazard improvements (1).
2. Add/improve roadway lighting (4).
3. Provide parking improvements (5).
4. Make driveway improvements (7).
5. Provide bike lanes (11).
6. Provide wide curb lanes (12).
7. Provide paved shoulders (13).
8. Perform repetitive and short-term maintenance (22), major maintenance (23), and institute a hazard identification program (24).
9. Provide chicanes or serpentine design or other traffic calming measures (26, 27, 28, 29).
10. Provide a separate path or trail (31).
11. Make sign improvements (37).
12. Improve pavement markings (38).
13. Provide bicyclist education about avoiding objects and correct spacing from parked motor vehicles (41).
14. Provide motorist education (42).

Possible Cause/Problem #3

The overtaking motorist detects the bicyclist ahead but fails to allow enough space to safely pass the bicyclist.

General Countermeasures

1. Make roadway surface hazard improvements (1).
2. Provide space on bridges and overpasses (2).
3. Provide space and other measures in tunnels and underpasses (3).
4. Add/improve roadway lighting (4).
5. Reduce lane width (on low speed roads) to encourage bicyclist to "take the lane" (10).
6. Provide space for bicyclists on high speed roadways with bike lanes (11), wide curb lanes (12), or paved shoulders (13).
7. Identify maintenance needs and perform routine and major maintenance (22, 23, 24).
8. Provide chicanes or chicane-like parking (26).
9. Provide a separate shared-use path (31).
10. Make sign improvements (37).
11. Improve pavement markings (38).
12. Provide bicyclist education (41).
13. Provide motorist education (42).

Possible Cause/Problem #1

The overtaking bicyclist strikes a motor vehicle while attempting to pass on either the right or the left.

General Countermeasures

1. Provide space for bicyclists with bike lanes (11), wide curb lanes (12), paved shoulders (13), or combination lanes (14).
2. Perform repetitive and short-term maintenance (22).
3. Perform major maintenance (23).
4. Institute a hazard identification program (24).
5. Provide a separate shared-use path (31).
6. Improve pavement markings (38).
7. Provide bicyclist education (41).

Possible Cause/Problem #2

The overtaking bicyclist strikes a parked motor vehicle or extended door of a parked motor vehicle while attempting to pass on either the right or the left.

General Countermeasures

1. Implement parking treatments (5).
2. Provide bike lanes (11).
3. Provide wide outside lanes (12).
4. Provide paved shoulders (13).
5. Provide a separate shared-use path (31).
6. Improve pavement markings (38).
7. Provide bicyclist education (41).
8. Provide motorist education (42).

Possible Cause/Problem #1

The bicyclist loses control due to a pavement surface irregularity, debris, or other hazard.

General Countermeasures

1. Make roadway surface hazard improvements (1).
2. Improve bridge access and surfaces (2).
3. Improve tunnel access and surfaces (3).
4. Add/improve roadway lighting (4).
5. Make driveway improvements (5).
6. Perform repetitive and short-term maintenance (22).
7. Perform major maintenance (23).
8. Institute a hazard identification program (24).
9. Implement "share the path" measures (34).
10. Improve pavement markings (38).
11. Provide bicyclist education (41).

Possible Cause/Problem #2

The bicyclist strikes a pedestrian, object or other bicyclist on a shared-use path, sidewalk, or roadway.

General Countermeasures

1. Make roadway surface hazard improvements (1).
2. Add/improve lighting (4).
3. Make parking improvements (5).
4. Implement maintenance countermeasures (22, 23, 24).
5. Provide path intersection treatments (32).
6. Provide path intersection advance warning treatments (33).
7. Implement "share the path" measures (34).
8. Improve pavement markings (38).
9. Provide school zone improvements (39).
10. Provide bicyclist education (41).

Possible Cause/Problem #1 (Non-Roadway)

A motorist and bicyclist collide in a parking lot or driveway. The motor vehicle may be backing at the time of the crash.

General Countermeasures

1. Add/improve lighting (4).
2. Redesign parking (5).
3. Make driveway improvements (7).
4. Perform repetitive and short-term maintenance (22).
5. Perform major maintenance (23).
6. Institute a hazard identification program (24).
7. Provide speed tables, humps, or cushions (27).
8. Make sign improvements (37).
9. Improve pavement markings (38).
10. Provide bicyclist education (41).
11. Provide motorist education (42).

Possible Cause/Problem #2 (Other)

Either the bicyclist or the motorist was traveling in the wrong lane or direction and collided head-on with the other. The bicyclist could have been riding on the wrong side of the roadway or the motorist could have been passing another vehicle when the crash occurred.

General countermeasures

1. Add or improve roadway lighting (4).
2. Provide bike lanes (11).
3. Provide paved shoulders (13).
4. Complete repetitive and short-term maintenance (general sight distance maintenance) (22, 24).
5. Provide law enforcement (40).
6. Provide bicyclist education about wrong-way riding and conspicuity and using lights at night (41).
7. Provide motorist education on safe passing (42).

Possible Cause/Problem #3 (Other)

Either the bicyclist or motorist made a turning error (swung too wide on a right turn or cut the corner on a left turn) and turned into the opposing lane or path of the other.

General Countermeasures

1. Install median divider (6).
2. Make driveway improvements (7).
3. Revise curb radii or re-align skewed intersections (16).
4. Install roundabout (17) or mini traffic circle (25) at intersection.
5. Add or improve intersection markings (18).
6. Impose turning restrictions (20).
7. Install raised intersection (30).

Possible Cause/Problem #4 (Other)

The bicyclist or motorist intentionally caused the crash, one or the other lost control due to impairment, mechanical problems, or other causes, or there were other unusual circumstances such as the bicyclist being struck by falling cargo. Few specific countermeasures can be identified for unusual or non-specific types of crashes other than educational and enforcement measures. To view general performance objectives and corresponding countermeasures to reduce crashes and encourage safer bicycling, go to the Performance Objectives section.