After fires destroyed multiple neighborhoods across Los Angeles County, many residents looked up to find blue, smoke-free skies this week. The Air Quality Index (AQI) — which measures the concentration of pollutants in the air — seemed to confirm all was well in the L.

Calculating air pollution from wildfires and other events has become more complicated. That doesn’t mean it’s necessarily more accurate.

The LA wildfires have burned tens of thousands of acres – but on some weather maps, air quality still looks good. What’s going on?

Air quality in wildfire-stricken Los Angeles improved on Thursday from hazardous peaks hit earlier this month, as tiny soot particles that can penetrate the lungs and brain dropped to moderate levels,

AirNow is a collaborative effort of federal agencies that provides air quality data across the U.S. The site also has up-to-date information about the wildfires, resources, data, and interactive maps to help users learn more about particular areas and how they might be affected. There's also a free AirNow mobile app.

A total of six towns in Monmouth and Ocean counties have unhealthy air and ozone levels, according to AirNow.gov.

Wear a tight-fitting N95 mask at the bare minimum, but a P100 is better, experts say. Wear long sleeves, eye protection, closed-toed shoes and cut-resistant gloves. Clean or decontaminate anything that’s been in contact with ash.

During the wildfires, several communities throughout LA County experienced poor air quality. Chris Chavez, deputy policy director for the Coalition for Clean Air, says many people are now breathing toxic air.

KCRW and R&S Kayne Foundation Los Angeles held a public information panel and Q&A session regarding immediate and long-term health considerations from the fires. Watch in English or Spanish.