2017DIN EN ISO 17637:2017-04 Non-destructive testing of welds - Visual testing of fusion-welded joints (ISO 17637:2016); German version EN ISO 17637:2016
2011DIN EN ISO 17637:2011 Non-destructive testing of welds - Visual testing of fusion-welded joints (ISO 17637:2003); German version EN ISO 17637:2011