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Introduction: US outdoor concentrations and racial-ethnicity disparities of criteria pollutants have declined on average during the decades since the 1990 Clean Air Act Amendments. We investigate how much different spatial levels contribute to overall racial-ethnicity disparity in US. Methods: We determine state-level decomposition with land-use regression model data, dividing overall disparity into inter-state and intra-state disparity. Inter-state disparity is used to determine disparity caused by living in different states. It’s calculated by population-weighted average for each racial-ethnicity group by setting all population in the same state with the same pollutant concentration, i.e. the state weighted average concentration. Intra-state disparity determines disparity caused by living in different places within the same state and it’s the difference between overall disparity and inter-state disparity. Another decomposition is based on spatial decomposition model at census block level, dividing pollution concentration into short, short-medium, medium-long and long range. Disparities at different ranges are population-weighted average of demographic data and range-specified air pollution data at the block level. Results: Black experience more intra-state disparity for CO, PM_2.5, PM₁₀ and NO₂ from 1990 to 2010. Inter-state disparity contributed more for CO, PM₁₀, and NO₂ for Hispanic and Asian in 1990, while intra-state disparity became more dominated for PM₁₀ and NO₂ for Hispanic in 2000 and 2010. Hispanic and Asian both experience an advantage from inter-state disparity for SO₂. Short-medium and medium-long range contribute most to overall disparity for all four race-ethnic groups for NO₂ while long-range disparity contributes most for all groups besides White for PM_2.5. Conclusions: Racial-ethnicity group can experience both advantage and disadvantage at different spatial levels. Overall disparity for NO₂ comes mostly from locally (intra-state; medium range) while PM_2.5 disparity related more with regional sources (inter-state; long-range). Temporal disparity decomposition showed NO₂ becomes more local-impacted and PM_2.5 becomes more regional-impacted from 2000 to 2010.