Based on AASHTO Chapter 9, intersection sight distance depends first on the intersection control type and the maneuver being checked, then grows as major-road speed increases. For stop- and yield-controlled movements, the required sight distance is further affected by design vehicle type, minor-road grade, the width to be cleared across lanes and median, intersection skew, and which maneuvers are legally permitted from the approach.
Some cases also depend on minor-road speed or vehicle length. In general, faster major-road traffic, heavier design vehicles, steeper upgrades, wider crossings, or more oblique intersections increase the required sight distance.
