These vibrations are transmitted to

These vibrations are transmitted to the freight from the truck's trailer bed, wheels and suspension.
The engine and transmission will also contribute to vibrations transmitted to the freight Measurements indicate that there is a continuous vibrations acceleration level of 0.5g at the lower frequencies. Design the package to avoid any of the natural frequencies listed above if they can cause damage to the product. A worse case condition would be a packaged product having a component or stack natural frequency matching one of the dominant forcing frequencies.
Shock acceleration levels are random in time Transient shocks occur when a truck hits potholes, expansion joints and railroad crossings. These shocks will cause products to jump off the floor and slam back down again. These transitory events overlay the dominant forcing frequencies that are often present. Transitory shocks can cause damage when freight is not properly blocked and braced. Stacked products, particularly those on top, can experience magnified acceleration levels as the energy is transmitted up through the load. The packaged products located in the middle and lower portions of a stack will experience dynamic compression. Collapsing could result if compression loads exceed the stacking strength of the container. This presents a danger of stack failure, where the top products could fall from heights of 80 inches or more, inducing impact shock