Key facts
- A federal appeals court upheld a ban on gas appliances emitting nitrous oxides in four Los Angeles-area counties.
- The ruling stated the ban does not conflict with federal law, specifically the Energy Policy and Conservation Act.
- The South Coast Air Quality Management District enacted the rule to reduce smog and meet federal ozone standards.
- The ban impacts large water heaters, small boilers, and process heaters, with compliance deadlines starting January 1.
- The court's majority found no clear congressional intent to block states from regulating appliance emissions.
A divided federal appeals court has upheld a ban on the manufacture, sale, and installation of gas appliances that emit nitrous oxides across four Los Angeles-area counties. The 9th U.S. Circuit Court of Appeals, in a 2-1 decision, rejected arguments from appliance makers and trade groups that the pollution control measure conflicted with federal law.
Circuit Judge Lucy Koh, writing for the majority, stated that the federal Energy Policy and Conservation Act does not prevent states from implementing reasonable regulations on appliance emissions. She argued that voiding the rule would amount to an implied repeal of the Clean Air Act, an outcome for which opponents had not shown clear congressional intent. Koh also noted that process heaters are not covered by the Energy Policy and Conservation Act, and the U.S. Department of Energy has not issued federal standards for them.
The South Coast Air Quality Management District enacted the zero-emissions rule for large water heaters, small boilers, and process heaters in June 2024 to combat severe smog and comply with federal ozone standards. Compliance deadlines began on January 1, and the regulation is projected to reduce emissions in the South Coast Air Basin by approximately 10%.
Circuit Judge Kenneth Lee dissented, drawing parallels to a 2023 ruling where the same court found federal law preempted a Berkeley ordinance banning natural gas infrastructure in new buildings. The National Association of Home Builders and several California business groups were among the entities challenging the ban.