In 2021, Gayatri Sehgal moved away from the fresh air of upstate New York and into the smog-choked city of Los Angeles. The pollution quickly made their asthma worse. On a given day, Sehgal might be short of breath or wheezing as their airways inflame.
“I’ve felt valid anxieties about the air,” the 28-year-old said. Their symptoms are bad enough that they don’t know if they can continue living in the region.
At a March 21 public meeting, Sehgal, a mental health worker focused on climate issues and an intern with the LA-area chapter of the Sierra Club, urged Southern California regulators not to delay in adopting clean air rules that would support the state’s plan to unleash millions of electric heat pumps — and net a major health win for residents like Sehgal.
Regulators are deciding just how much to heed appeals like these. The South Coast Air Quality Management District is weighing new rules to reduce emissions of nitrogen oxides, or NOx, the smog-forming byproducts of combustion, by limiting the sale of home gas-fired furnaces and water heaters. About 10 million of these fossil-fueled appliances are currently installed throughout the region, home to more than 17 million residents across Los Angeles, Orange, Riverside, and San Bernardino counties.
Although an earlier draft of the rules would have effectively banned the sale of gas-fired units, the agency’s staff walked back the idea after vigorous opposition from industry, business organizations, city governments, and others.
Now, the agency is proposing to allow manufacturers to gradually ratchet down the amount of gas equipment they sell so long as they pay nominal mitigation fees. Starting in 2027, manufacturers would be required to aim for a sales target of 30% for appliances that meet zero-NOx emissions standards, i.e., heat pumps and heat-pump water heaters. The fraction would increase to 90% by 2036, but the rules would never require sales of gas appliances to actually stop.
Some advocates are still pushing for updates with stronger teeth, saying the proposed fees are likely too small to get manufacturers to comply. But over two years into a prolonged process that has only diluted the initial proposal, supporters are also urging the agency to get the rules done as soon as possible and lock in their considerable health and environmental benefits. The full board for the district is expected to vote on the rules on June 6.
NOx emissions are a nationwide problem that many states are actively working to solve. But the challenge is especially urgent in Southern California, which has some of the worst air quality in the country, according to the American Lung Association, a supporter of stronger draft rules.
“We fail to meet several federal air quality standards,” said Sarah Rees, deputy executive officer at the air district, the oldest in the nation. “We really need to take all actions that we can to reduce those emissions.”
Most NOx is from transportation sources, which are regulated by state and federal agencies. But under the SCAQMD’s jurisdiction are the fossil fuel–burning appliances in residential and commercial buildings. These pollution sources are responsible for roughly 76,000 asthma attacks, 30,000 lost school days, and 130 premature deaths each year, according to the advocacy group Coalition for Clean Air and climate think tank RMI. The annual health costs total about $2 billion.
The district first set NOx emission limits on residential space heaters with Rule 1111 and residential water heaters with Rule 1121 in 1978. Regulators have progressively strengthened them over time, first beginning to consider the shift to zero-emission equipment in 2016.
Though the proposed updates to the rules don’t represent a wholesale shift to NOx-free units, they could still reduce NOx emissions by 6 tons per day by 2060. For comparison, the more ambitious rules, which included space heaters in commercial buildings, would have enabled the South Coast to eliminate 10 tons of NOx per day by 2054.
Still, 6 tons per day is “a pretty big chunk,” Rees told Canary Media. “It’s about 10% of all of the stationary source emissions [from every factory, refinery, power plant, etc.] in our region.”
The public health benefits would be enormous, according to the district’s socioeconomic impact analysis: more than $25 billion from 2027 to 2053, including about 2,500 lives saved.
Zero-NOx emissions standards taking off
Zero-NOx standards for new home appliances aren’t a new concept. San Francisco Bay Area regulators adopted such rules in 2023, and the California Air Resources Board is developing a similar proposal for the entire state.
The trend is growing outside of California, too. Maryland is developing zero-emissions rules for heating homes and businesses, and in 2023, eight more states — Connecticut, Hawaii, Massachusetts, New York, Oregon, Pennsylvania, Rhode Island, and Washington — committed to exploring such standards.
The South Coast also has a recent history of health- and climate-aligned rulemaking. In 2023, regulators adopted a first-of-its-kind rule to electrify large commercial bakeries and kitchens. In 2024, they passed another landmark rule to electrify small industrial boilers and large water heaters.
However, this time, critics got the district to refrain from requiring new space and water heaters be electric.
