Loose Cargo Bounce Testing

Shipping containers carrying military and civilian hardware often spend a considerable amount of time in the backs of transport trucks. When the cargo travels off road being delivered to remote fields of operation, the ride can be quite rough. Items that see rough road duty may be encased telephones, laptops, missiles or medical equipment, and regardless of the journey, the gear has to work upon arrival.

The military designed the loose cargo test section in MIL-STD-810 to simulate the motion of an unrestrained container as it repeatedly collides with the walls and floor of a four-sided enclosure (and other cargo) in a semi-elliptical trajectory. This test usually runs for 45 minutes and simulates approximately 150 miles (240 km) (all three axis simultaneously) of transport. This process requires a special, low rpm (300 rpm), low frequency (5 Hz), and small displacement (2.5 cm / 1 inch) test bed package tester.

The International Safe Transit Association (ISTA) developed a civilian package test procedure resembling the military test: 1A for products weighing less than 150 lb (68 kg) and 1B for over 150 lb (68 kg). Additional tests in subsequent procedures such as 1C, 1D, 2A and further combine the loose cargo basic test with atmospheric conditioning and other factors. More details on NTS ISTA Package Testing can be found here.