This research investigates how the current friction design standard should be improved, specifically for monopile sea fastening with polymers. Literature and results from tests performed previously to this research are investigated in order to obtain a complete overview of the factors that should be considered in the design standard. Additional tests are carried out on factors for which literature and previous test exercises are inconclusive. Friction test methods are compared to determine the best method for testing monopile sea fastening friction. The total test variability is analyzed to determine why safety measures are required. The validity of these measures is studied with a large set of test results. Finally, modelling as an alternative for testing is investigated.