The biennial review of atomic weightAr(E), determinations, and other cognate data has resulted in changes for the standard atomic weight of indium from 114.82±0.01 to 114.818±0.003, for tungsten from 183.85±0.03 to 183.84±0.01, and for osmium from 190.2±0.1 to 190.23±0.03 due to new high precision measurements. Recent investigations on silicon and antimony confirmed the presently acceptedArvalues. The footnote ‘‘g’’ was added for carbon and potassium because it has come to the notice of the Commission that isotope abundance variations have been found in geological specimens in which these elements have an isotopic composition outside the limits for normal material. The value of 272 is recommended for the14N/15N ratio of N2in air for the calculation of atom percent15N from measured &dgr;15N values. Because many elements have a different isotopic composition in nonterrestrial materials, recent data on nonterrestrial material are included in this report for the information of the interested scientific community.