How is air quality after El Segundo refinery fire?

A massive fire that broke out at the Chevron refinery in El Segundo on Thursday night sent flames and smoke into the air, shaking nearby homes and alarming residents, but experts say air quality impacts have so far been limited.

The blaze, reported around 9:30 p.m., burned through the night before crews gained control by Friday morning.

Air quality experts say Los Angeles was fortunate that weather conditions pushed the smoke away from the city.

Suzanne Paulson, a professor of atmospheric and oceanic sciences at UCLA and director of the UCLA Center for Clean Air, explained that wind direction played a key role.

“Fortunately for Los Angeles, the winds were in our favor for this event,” Paulson said. “Last night, winds were mostly either blowing the smoke offshore. More specifically, they blew from that fire along the coast (from south-southeast to north-northwest) moving to completely offshore (from east to west) as the night went on.”

By Friday morning, winds had begun to shift. Paulson noted that “by the afternoon they would be coming from the west, so smoke from the fire would come across the city.” Still, she emphasized that breezy conditions were helping reduce concentrations.

“The smoke is detectable by the Purple Air and Clarity Air low cost sensor networks, as well as in AQMD monitoring. None of the data indicate that the smoke impacted the city last night,” she said. “Even the Purple air sensors in El Segundo were not particularly elevated last night.”

While officials continue to monitor air quality and assess potential impacts, Paulson’s comments suggest that widespread exposure was avoided due to favorable winds and dispersal conditions.

The cause of Thursday’s fire remains under investigation.