M
PTV,random
0.7σ
= 1.64·(√(σ
2
+σ
p
) – σ
)
σ [mm]
[mm]
σ
= 3.2 mm
PTV
= 2.5Σ+ 0.7σ
Add random errors
= 2.5Σ + 0.7σ