The test design must include a number of different drop and shocks both on corner edge and side. Corner drop can easy be reproduced. You just drop against a hard floor. Edge and side drops can only be reproduced using equipment, either a drop tester or a shock tester. A drop tester (drop table) is a plate mounted over the floor. The plate is constructed together with a mechanism able of moving fast away from the parcel in a way so that the parcel can start a free drop without any rotation. If you use you hands a little rotation is transferred to the parcel and results in a corner drop.
It is a practical experience that this difficult side drop also affects the product worst. The explanation is that the side drop only gives one big impact.
The area under the curve is the energy in the drop. The green, blue and red areas are the same.