tokens: For Earth orbits other than those addressed in 9.2.1.2 , the standard models of the radiation belt energetic particle fluxes shall be the AE-8 and AP-8 models for electrons [ RN.10 ] and protons [ RN.11 ] . NOTE 1 These models are based on long term dataset averages and are most appropriate for long term cumulative effects on missions of more than 6 months duration . Statistical variation and uncertainties can be significant and are presented in Annex I.