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Reviewing National Ambient Air Quality Standards (NAAQS)

Sulfur Dioxide (SO2) Standards - Risk and Exposure Assessments from Current Review

The quantitative risk and exposure assessments inform the EPA's review of the NAAQS.

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Risk and Exposure Assessment for the Review of the NAAQS for SOx (PDF)(515 pp, 21 MB, 05/09/2018)
Risk and Exposure Assessment for the Review of the NAAQS for SOx, External Review Draft (PDF)(456 pp, 15 MB, 08/24/2017)
Memorandum Regarding CASAC Request for data associated with Appendix D of the draft REA (PDF)(4007 pp, 8 MB)