Adjusting Sight Distance for Skew

[Daisy]

I'm looking at a SSD analysis for a highway-rail at grade crossing, with a 70 degree skew. Can anyone direct me to a reference telling me how to adjust SSD for skew? I can't find anything in the Green Book, although it says it must be done. Any thoughts are appreciated!

 

[TXCoogPE]

Try looking at the "Railroad-Highway Grade Crossing Handbook." There is a .pdf link to it on the FHWA website.