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Sight Distance Calculator

Calculate Stopping Sight Distance (SSD) and Overtaking Sight Distance (OSD) per KRDM/KeRRA

Stopping Sight Distance
85m
SSD = Vt + V²/254(f+g)
Overtaking Sight Distance
298m
OSD ≈ 3.5 × SSD
Curve Radius Check
SSD vs curve radius:✓ Adequate

Minimum SSD (per KRDM2017)

Speed (km/h)SSD (m)OSD (m)
3030m105m
4045m158m
5065m228m
6085m298m
70110m385m
80140m490m
90175m613m
100215m753m
110260m910m
120305m1068m

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