At Shark, we use the drop-tester shown here to produce impacts up to 10G-force on the shock absorber boat seat. Those tests are in accordance with test protocols defined by the UK Ministry of Defence and have been independently verified at the UK MOD testing facility called RAFCAM. The protocol requires that the impact lasts 100ms (a tenth of a second) and has a peak amplitude of 10G. The UK MOD protocol defines a method of calculating the amount of protection provided by the shock absorber boat seat called SEAT value (also known as MR or Mitigation Ratio). The lower the percentage of this value; the better suspension performance.
In the case of the test shown, the 70kg payload would experience a shock of 10 times its weight (or 700kg) for a tenth of a second, if it were not for the suspension reducing that impact. In this graph, you can see the impact on the weight is reduced significantly and it is slower which allows a person’s body to respond to it. You can see from the start of the video that at normal speed the impact is so fast that a person cannot react in time. A clearer motion of the seat and impact force is shown when the video is replayed at 20 and then 40 times slower than normal speed. This video is not the best nor the worst result, just a typical one and we perform this test for payloads from 40kg to 100kg. In this instance, the SEAT value is a creditable 65%.