Height: 120cm.Investigation: visual inspection: in the first step of our investigations, an optical control is carried out.It is checked whether any defects, deformations or other noticeable irregularities can be identified.Permeability test: to proof the penetrability of the valves we have carried out penetrability tests.These tests are carried out at a calculated hydrostatic high (open pressure of the valves + 30cmh2o) in horizontal direction of flow.Adjustment test: the adjustment test is used to ensure that the progav 2.0 can be adjusted to all pressure levels.The tests are carried out with the standard progav 2.0 check-mate and measurement tool.The valve is adjusted from 0 to 20 cmh2o and down again in increments of 5 cmh2o.Braking force and brake function test: to measure the braking force, we tested the progav 2.0 valve with a braking force apparatus.Here it is measured how much force must be exerted on the housing to release the rotor to adjust the valve by the integrated magnet of the braking force apparatus.Results: no significant deformations or damage of the valves were detected during the visual inspection.Next we tested the permeability and opening pressure of the valves.Both valves were shown to be permeable and their opening pressures were operating within specifications.Additionally, we tested the adjustability as well as the brake functionality and brake force of the progav 2.0 valve.The valve operated as expected and met all specifications.Finally, we have dismantled both valves.Inside both valves, we have found visible slight build-up of substances (likely protein).Based on our investigation, we are unable to substantiate the claim of occlusion.At the time of our investigation, the valves were shown to be permeable.At the time of the investigation, we are not able to determine how the functional impairment mentioned above occurred in the past.However, we suspect that the significant deposits found inside the valves have led to the functional impairment in the past.We can exclude a defect at the time of release.The shunt system met all specifications of the final inspection when released from christoph miethke (b)(4).
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