Division 3.4.2.4

The required impact velocity, the direction of impact and the upper legform impactor mass shall be determined as specified in points 3.4.2.6 and 3.4.2.7. The tolerance to the impact velocity is ± 2 % and the tolerance to the impact direction is ± 2°. The effect of gravity shall be taken into account when the impact velocity is obtained from measurements taken before the time of first contact. The upper legform impactor mass should be measured to an accuracy of better than ± 1 %, and if the measured value differs from the required value then the required velocity should be adjusted to compensate, as specified in point 3.4.2.7.