ISO 14253-1:2013 establishes the rules for determining the conformity or nonconformity with a given tolerance for a characteristic of a workpiece (or a population of workpieces) or limits of maximum permissible errors for a metrological characteristic of a measuring equipment, taking into account the measurement uncertainty.These rules are different for tolerances to individual workpieces and tolerances to workpiece populations.It also gives rules on how to deal with cases where a clear decision (conformity or nonconformity with specification) cannot be taken, i.e. when the measurement result falls within the uncertainty range that exists around the specification limits.ISO 14253-1:2013 applies to specifications defined in general GPS standards (see ISO/TR 14538), i.e. standards prepared by ISO/TC 213, including:? workpiece/population of workpieces specifications (usually given as an upper tolerance limit or a lower tolerance limit or both), and;? measuring equipment specifications (usually given as maximum permissible errors).ISO 14253-1:2013 only applies for characteristics expressed as numerical quantity values.