The results of the analysis of radioiodine annual specific emission rates into the atmosphere from USA nuclear power plants (NPP) during 2005-2018 are presented. The median values for 131I, 132I, 133I and 135I specific emission rate from NPP with PWR were, 10-7 GBq/(GWh): 1.14, 5.57, 1.64 and 2.30, respectively. The medians for 131I, 132I, 133I and 135I emissions from NPP with BWR were, 10-5 GBq/(GWh): 0.29, 2.6, 1.65 and 2,09, respectively. The ranking of US NPPs according to the categories of «best», «worst» and «sustainable» practice of iodine isotopes emissions into the atmosphere has been carried out. The use of median values of the specific emission rates from the «best» practice category as the main guidelines for the design of new NPP is consistent with the basic principle of the INPRO methodology. In this case the environmental impact of radioiodine emissions will not exceed levels typical for operating facilities. Fig. 1, tab. 4, ref. 19.