ARM 38.4.407. OVERHEAD CLEARANCE -- ALL OTHER STRUCTURES

(1) Minimum overhead clearance as prescribed in ARM 38.4.404 may be decreased to the extent defined by the half-circumference of a circle having a radius of eight (8) feet six (6) inches and tangent to a horizontal line twenty-two (22) feet six (6) inches above top of rail at a point directly over the centerline of track.