NF EN ISO 13920, A89-300 (06/2023)

This document specifies four classes of general tolerances relating to linear and angular dimensions as well as the shape and position of welded structures, based on current shop accuracy. The main criterion for choosing a particular tolerance class is based on the functional requirements that must be met. The applicable tolerances are always those indicated on the drawing. The tolerance classes mentioned in this document may be used in place of individually specified tolerances. The general tolerances for linear and angular dimensions as well as shape and position specified in this document apply to weldments, welded joints, welded structures, etc. Special provisions may be necessary for complex structures. The specifications presented in this document are based on the independence principle of ISO 8015, according to which dimensional and geometric tolerances apply independently of each other. Manufacturing documentation in which linear and angular dimensions or indications regarding shape and position are presented without tolerances being indicated individually must be considered incomplete if reference is not made (or if reference is made inadequate reference) to general tolerances. This does not apply to provisional dimensions.
(Automatic translation from French)