Author:  Dr. Bernard S. Abrams

Date of Publication:  May 4, 1992

Abstract:

Railroad-highway grade crossing safety involves two major components - the highway and the railroad and each has multiple sub-components, in addition the grade crossings (6) are divided by traffic engineer into active and passive classifications (7). The crossings are required by law to be minimally signed as designated in the Manual of Uniform Traffic Controls.

This limited study has taken into consideration certain elements of risk associated in passive railroad crossings which are believed to be a result of their components or lack of components. Reviewing available literature indicates the current prime source of driver warning at passive crossings is the standard crossbuck configuration which to the best of this author’s research is over 100 years old (8).

Additional research by this author indicates both severity and certain numbers of accidents at passive crossing can be related directly to inadequate visual sight triangles (9) and lack of cognitive discernibility of signs and locomotives at a sufficient distance both of which created ultra hazardous conditions. These factors relate directly to visual data passing over the visual pathway. It is widely acknowledged that over 90% of the information required to operate a train or vehicle must pass over the visual pathway system. In order for a warning to be sufficient, we have to analyze its visual effectiveness and know the distance it will be cognitively discernible (10). An evaluation was made by creating a 90 degree light triangle* consisting at the corner of a “Buckeye” crossbuck. At one 45 degree corner we placed a locomotive equipped with various headlights (train tracks) and at one 45 degree corner a vehicle with headlights of both low and high beam (Berlin Station Road) on the opposite side of the track was a similar crossbuck.

The results clearly indicated that the recently designed “Buckeye” crossbuck system provides visual advantages that significantly increases the early warning sight distance for vehicular drivers during both daytime and nighttime on the adjacent leg.

An additional by product of this study was the finding of a distinct advantage for vehicle drivers of binocular visual cues of locomotive distance, location and perception due to the horizontal angular separation by use of dual ditch lights.

The main body of this portion of the study consists of further subjective sections.

On two different occasions quantitative light measurements were obtained by R. McGuinness and will be reported in a separate section.

A preliminary review of his data indicates value of ditch lights and comparison of two bulb luminance readings.
 

No. of Pages:  48