Tag Archives: “adequate margin of safety”

EPA Will Reconsider the Ozone NAAQS — What Is An Adequate Margin of Safety, Anyway?

On Friday, EPA announced that it was reconsidering its 2020 decision to leave the National Ambient Air Quality Standards for ozone unchanged.  The reconsideration will be based on the existing record.  The notice does not identify any specific perceived flaws in the 2020 decision.  However, EPA stated that it:

will reconsider the decision to retain the ozone NAAQS in a manner that adheres to rigorous standards of scientific integrity.… More

EPA’s Latest Particulate Review Shows Impacts Below the Current NAAQS. How Will Trump Avoid Doing Something About It?

Last week, EPA posted its draft Integrated Science Assessment for Particulate MatterIt’s the foundational document for EPA’s periodic review of its National Ambient Air Quality Standard for PM.  The current standard for PM2.5, promulgated in 2012, is 12 ug/m3.

Section 109 of the Clean Air Act requires the Administrator to set the NAAQS “requisite to protect the public health” with “an adequate margin of safety.”

The new ISA states that:

Evidence from U.S.… More