The role of NAA in securing the accuracy of analytical results in the inorganic trace analysis

The unique value of the neutron activation analysis (NAA) for analytical quality assurance is demonstrated through its contribution to the certification of the reference materials over the time span of 40 years. Ratio primary reference measurement procedures i.e. definitive methods, based on radiochemical NAA, play an important role in confirming the validity of the certified values established in the international intercomparisons. Real analytical situations where the use of NAA was critical to get accurate results are presented. The dangers associated with the possible non-availability of the NAA in the near future are indicated.