Transcript The Effectiveness of Wider Edge Line Pavement Markings
The Effectiveness of Wider Edge Line Pavement Markings February 2012 Sponsored by: AGBMA
Wider Lines Synthesis, 2002 • Included: – US practices – International practices – Review of literature – Suggestions for research
Terminology • Standard edge line width = 4 inch – The standard for over 60 years • Wider edge line width = 6 inches – A recently proven low-cost safety countermeasure
Adding a 4-inch Edge Line • Benefit/cost ratio of 60:1 (Miller)
What happens if we increase the width of the edge lines?
Prior to 2011…
New findings released in 2011 at June NCUTCD
Safety Effects of Wider Edge Lines on Rural, Two-Lane Roads
Publications • FHWA Final Report – Submitted Dec 31, 2011 – In publication office • Journal Accident & Analysis Prevention – Paper accepted in January 2012 – Current in press
Summary of Safety Effects
Crash Type
Total Fatal and Injury Day Night
Percent Reduction
15.0 – 30.1
15.4 – 37.7
12.0 – 29.1
-2.4 – 30.7 • • • Kansas from 2001-2007, almost 1300 miles Michigan from 2001-2009, 787.8 miles Illinois from 2001-2006, 287 miles
Comparative B/C Analysis • • • • Used disaggregated fatal and injury crash reduction findings from Kansas data Used crash cost values from NHTSA inflated to 2011 dollars Assumed 22 of injuries were disabling injuries and 78 were minor injuries Assumed waterborne paint: – $0.15 per foot for 6-in markings – 2 year service life
Treatment
Wider Edge Lines Rumble Strips Chevrons RRPMs Findings
B/C Ratio
$33 - $55 per $1 $37 - $46 per $1 $9 - $46 per $1 $13 per $1
Questions Paul J Carlson, Ph.D., P.E.
Texas Transportation Institute 979-845-1728 [email protected]