Midnight Watch: Clean Air

National Ambient Air Quality Standards for Ozone

In August 2020, the Environmental Protection Agency (EPA) proposed to retain the existing National Ambient Air Quality Standards (NAAQS) for ozone, despite significant new scientific evidence of ozone’s harm to human health that has emerged since the existing standards were adopted in 2015, as state attorneys general noted in comments filed in October 2020. The attorneys general also noted significant flaws in the process by which the EPA reached its decision, including steps to arbitrarily exclude scientific experts, truncate and eliminate important steps, reduce transparency and curtail opportunities for public input.

🔴NEW DEVELOPMENTS: The EPA published its final decision on December 31. A coalition of 16 state attorneys general challenged the decision on January 19.

National Ambient Air Quality Standards for Particulate Matter

In April 2020, the EPA proposed to retain the existing NAAQS for fine particulate matter (PM2.5) and coarse particulate matter (PM10), even though fine particulate matter is associated with an estimated 45,000 deaths annually in areas that meet existing standards, as state attorneys general noted in comments filed in June 2020. The attorneys general also noted that the EPA wrongly asserted that its decision “raises no environmental justice issues,” despite significant evidence that communities of color and lower-income communities are disproportionately exposed to and harmed by PM pollution.

🔴NEW DEVELOPMENTS: The EPA published its final decision on December 18. A coalition of 17 state attorneys general challenged the decision on January 15.

Once In, Always In

On November 19, the EPA published a final rule replacing its 25-year-old "Once In, Always In" policy, which required that once a facility is classified as a major source of hazardous air pollutants it must keep pollution controls in place even if the facility has the potential to reduce emissions below major source thresholds. The agency previously adopted a similar policy through a guidance memorandum; the U.S. Court of Appeals for the D.C. Circuit dismissed a challenge to the guidance memorandum, holding that it was not a final agency action.

🔴NEW DEVELOPMENTS: A coalition of 13 state attorneys general challenged the final rule on January 19.

Emissions Standards for Ethylene Oxide

In December 2019, the EPA published an advance notice of proposed rulemaking to solicit input on potential revised emissions standards for ethylene oxide (EtO), a flammable and highly reactive gas used by more than 100 facilities across the United States to sterilize medical instruments and other products. In comments filed in February 2020, state attorneys general noted that existing standards fail to adequately protect 288,000 Americans across 36 states who face an elevated risk of EtO exposure, which is associated with cancer, reproductive harm and neurotoxicity. The attorneys general also noted that a statutorily mandated review of the standards is more than five years overdue, and urged the EPA to work with the Food and Drug Administration (FDA) to support research into effective alternatives to EtO sterilization. The EPA has thus far not moved forward with proposing revised standards. 

Sell-Through Period for Non-Compliant Wood Heaters

In May 2020, the EPA published a proposed rule that would have allowed the continued sale of wood-burning heaters, boilers and forced-air furnaces that do not comply with emissions standards that took effect in May 2020. Air pollutants emitted by such appliances — in particular, fine particulate matter — cause significant harm to public health, and are particularly dangerous during a respiratory disease pandemic. The proposal would have allowed retailers to continue selling non-compliant products through November 30, 2020, despite the fact that the EPA previously concluded that there was insufficient evidence of a need for a sell-through period, as state attorneys general noted in comments filed in July 2020.

🔴NEW DEVELOPMENT: In mid-November, the EPA reportedly notified industry groups that it would not finalize the proposed sell-through period for non-compliant wood heaters.