This European Standard specifies requirements for strength graded structural timber with rectangular cross-sections either visual or machine graded, shaped by sawing, planning or other methods and with cross-sectional dimensions complying with EN 336 (referred to as structural timber in the following clauses). This European Standard includes provisions for test methods, Assessment and Verification of Constancy of Performance and marking of structural timber. NOTE 1 For machine strength graded timber additional provisions for type testing (TT) are given in EN 14081-2 and for factory production control (FPC) in EN 14081-3. NOTE 2 An acceptance procedure for verification of a lot is given in EN 14358 which may be used for a delivery of structural timber. This European Standard identifies characteristics for which limits have to be given in visual grading standards. This European Standard covers structural timber, untreated or treated against biological attack. This European Standard does not cover: - timber treated by fire retardant products to improve its fire performance; - thermally and/or chemically modified timber; - structural finger jointed timber.