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Reducing Flangeway Gaps at Railroad Crossings to Better Accommodate Pedestrians

The Americans with Disabilities Act Accessibility Guidelines (ADAAG) require that gaps in pedestrian paths (sidewalks and crosswalks) not exceed 1/2 inch.  The Draft Guidelines for Accessible Rights of Way (June 17, 2002) allow pedestrian paths crossing railroads at grade to have a 2-1/2 inch gap on the inside of the rail for the railroad car’s wheel flanges (3 inches are allowed for tracks carrying freight).  The Public Rights-of-Way Accessibility Advisory Committee recommended that this exception expire since these larger gaps can trap  wheelchair wheels (manual and motorized, motorized mobility scooter wheels, other mobility aids (i.e. a walker, a cane, crutches or braces) and in some cases, the feet of pedestrians.  That committee recognized, however, that no technology exists to reduce the gap without increasing the likelihood of train derailment.  Flangeway fillers that are currently available do not hold up to the weights and speeds of travel common on freight systems. That committee stressed the need for research to find a solution to this problem. This problem exists for both heavy and light rail.  However the problem is more critical at heavy rail crossings, particularly where there is freight train traffic. As an increasing amount of light rail installations interface with current street infrastructure more pedestrians, particularly those  using mobility aids, will be affected by this issue.  Many heavy and light rail commuter stations have access to the platforms, which cross the tracks.  Finally, communities are installing paved, pedestrian paths that cross railroads separately from roadways and sidewalks.


Literature Search Summary: Despite the mention in DOT reports as early as 1980, no research related to this matter since that time is known to exist. Limited commercial entities have developed flangeway fillers but these technologies have not received extensive objective evaluation.  There is significant anecdotal information on the limited success of existing technologies. Studies are needed to evaluate the success of light rail treatments and to research and develop solutions for heavy rail crossings. 


Research Objective: The objective of this research is to develop promising designs for a flangeway gap that meet ADAAG requirements for pedestrian path gaps and do not endanger trains.  Successful designs will be rigorously field tested in a subsequent effort.


Task 1.  Search existing documents and resources, including existing or recent installations or concepts.  While it is believed that no successful installations exist except in very low speed, low rail-traffic situations, there is always the possibility that this belief is not correct.  In cases where flangeway fillers have been installed but have failed, the failure mode should be described.


Task 2.  Test flangeway fillers or other concepts to scientifically document the reasons for failure with the goal of seeing how the designs could be changed to allow them to be successful.  This research could also develop parameters for successful performance. 


Task 3.  As designs are developed, evaluate them for two basic safety criteria.  First, providing for the safe passage of trains without derailment under actual conditions of service, including climate, weather, and grade crossing environment conditions such as dirt, debris, and casual vandalism.  Second, but equally important, is to provide a safe crossing for pedestrians, particularly those using mobility aids,  under these same conditions.  For flangeway fillers, this second criteria means that after the passage of a train they will reliably return to a position that provides a safe crossing for pedestrians and mobility aid  users that have, through previous use of that crossing, come to expect that flangeway gaps at that crossing will not be present.


Task 4: Complete a final report recommending one or more solutions.  The final report would be expected to address estimated costs to construct and install each of the solutions.  It could also contain a plan for implementation over a given period.


Estimate Funding And Research Period:

Total Funds Requested: $400,000

Research Period: 30 months


Urgency, Payoff Potential, And Implementation: Very High to Meet ADA Requirements

The number of crosswalks and sidewalks crossing railroad tracks is not known but is considerable, particularly in areas with light rail transit.  The U.S. Access Board has resisted pressure to terminate the exemption for railroad tracks but this may change. 


If successful, the research will increase the safety and efficiency of pedestrians using wheelchairs who cross railroad tracks, while not substantially impeding the public safety benefits derived from the use of rail facilities by passengers and freight instead of alternative, less-safe, modes.


Submitted By:

TRB Committee AHB60 – Highway-Rail Grade Crossing

AASHTO Standing Committee on Rail Transportation


Sponsor and Supporter of the Problem Statement:

TRB Committee ABE60 – Accessible Transportation and Mobility


Person(S) Developing The Problem April 2008

Paul Worley

North Carolina DOT


William Browder

American Association of Railroads


Richard Raub

Raub Associates, Portland

Sponsoring Committee:AHB60, Highway/Rail Grade Crossings
Date Posted:05/27/2008
Date Modified:05/28/2008
Index Terms:Americans with Disabilities Act, Grade crossing protection systems, Railroad grade crossings, Flanges, Flangeways, Derailments, Pedestrian collision models,
Cosponsoring Committees: 
Operations and Traffic Management
Safety and Human Factors

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