Despite Tuesday’s green map from the South Coast Air Quality Management District, showing air quality in Los Angeles County was “good,” people should continue to take precautions outdoors, as a windblown dust and ash advisory remains in effect until Wednesday evening.
“In most situations (the AQMD map) provides the whole picture. This is sort of a unique situation where we have a lot of ash down at levels where people live that could pose a health issue and won’t show up on our AQI map,” said Dr. Scott Epstein, air quality assessment manager at AQMD.
So the agency added a disclaimer above the map: “Windblown ash particles may be too large to be detected by air quality instrumentation and not reflected in the Air Quality Index (AQI) map. However, they are typically visible to the naked eye either in the air or on outdoor surfaces. Although the AQI may show green, hazardous ash may be present in the air. If you smell smoke or see ash, please take precautions.”
The Air Quality Index accounts for common pollutants found in urban areas with well-defined health standards, including particulate matter such as fine particle pollution found in smoke. With less smoke being released from wildfires this week, the AQMD map measured a reduced presence of fine particle pollution in the air without accounting for other pollutants such as ash particles — which are difficult to measure, Epstein said.
“Strong winds are expected to continue dispersing ash and dust from burn scars in the Palisades, Eaton, and other impacted areas. Air quality may reach levels that are unhealthy for sensitive groups or worse in some regions,” the Los Angeles County Public Health Department said in a statement Tuesday afternoon.
Wildfire ash carries many carcinogens that could cause short- and long-term health problems, including asthma attacks and difficulty breathing.
If you’re in an area downwind of recent burn scars, be on the lookout for ash, which can look like small gray or white particles, usually the size of a sand grain or larger, officials said.
Most importantly, don’t breathe it in. Wear an N95 mask when spending time outside and avoid using a leaf-blower to clear the ash outside, as it can be stirred back into the air and re-inhaled. Instead, spray the area down with water and sweep it up.
“The best place to be is inside with your windows and doors closed,” Epstein said.