Effect of friction stir welding on hydrogen content of ISO 3183 X80M steel

•FSW reduces the risk of HIC in comparison to conventional fusion welding processes.•FSW does not have a significant influence on the hydrogen concentration.•The hydrogen pickup during FSW is not increased when the steel surfaces are oxidized.•Hydrogen generation due to water decomposition is not expected during FSW.•An adaptation of ISO 3690:2012 and AWS A4.3 1993 procedures to FSW is made.