- 📌 The South Coast Air Quality Management District (AQMD) issued a particle pollution advisory for July 4-5, 2026, warning of unhealthy air quality across most of Los Angeles County.
- 📌 Fireworks release large amounts of PM2.5 and PM10 particles and toxic metals, posing risks to cardiovascular and respiratory health.
- 📌 The advisory is in effect from Saturday, July 4 at 5 p.m. until Sunday, July 5 at 3 p.m., with light winds expected to trap smoke.
- 📌 Residents are urged to stay indoors, run air conditioners/purifiers, and avoid vigorous activity.
- 📌 Similar warnings have been issued for the National Mall in Washington, D.C., and other major cities due to record-breaking heat and larger-than-usual firework displays.
AQMD Issues Particle Pollution Advisory for July 4 Fireworks
As Southern California gears up for Independence Day celebrations, the South Coast Air Quality Management District (AQMD) has issued a particle pollution advisory warning of hazardous air quality from fireworks. The advisory covers most of Los Angeles County, including Downtown, the San Fernando Valley, and the San Gabriel Valley, from Saturday night through Sunday afternoon. Hazardous levels of air pollution are expected across central and southern Los Angeles County, northern Orange County, and Riverside and San Bernardino counties from 5 p.m. Saturday evening through 3 p.m. Sunday, according to the South Coast Air Quality Management District. Unhealthy air quality is also expected in northern Los Angeles County and southern Orange County.
What the Advisory Says
According to the AQMD, fireworks release large amounts of particle pollution (PM2.5 and PM10) and air toxic metals. Breathing these particles can lead to cardiovascular and respiratory health effects, including heart attacks, asthma aggravation, decreased lung function, coughing, difficulty breathing, and even premature death in people with heart or lung disease. The advisory is in effect from Saturday, July 4 at 5 p.m. until Sunday, July 5 at 3 p.m. Pollution levels are expected to build from dusk onward Saturday, as light winds and increased firework activity lead to an increase in smoke, a South Coast AQMD advisory said. Soot and particulates will likely linger through Sunday afternoon before being dispersed by the wind.
Health Risks and Recommendations
Individuals with heart or lung conditions, the elderly, and children are especially vulnerable. The AQMD recommends staying indoors with doors and windows closed, running air conditioners or air purifiers, and avoiding the use of whole house fans or swamp coolers that can bring polluted air indoors. If it's too hot to keep windows closed, residents should seek refuge in public places like libraries or shopping centers. Anyone experiencing severe symptoms such as difficulty breathing, chest pain, or palpitations should call 911. Firework-related pollution can trigger coughs, breathing problems, asthma flares and heart attacks, according to Los Angeles County Public Health, and anyone experiencing severe or worsening cardiovascular symptoms like chest pain or difficulty breathing should seek medical attention immediately. Pyrotechnics set off at home are even more likely to trigger cardiovascular problems, the American Lung Assn. says, as the burst of pollutants takes place closer to the ground.
The National Weather Service has issued an air quality alert for Pasadena and the rest of the San Gabriel Valley, warning of harmful fine particle pollution from fireworks that is expected to last until 3 p.m. Sunday, July 5. The alert, based on a South Coast Air Quality Management District (AQMD) advisory, covers most of Los Angeles County. Particle pollution levels can vary by time and location depending on emissions and local weather conditions, meaning some areas of Pasadena and surrounding communities could see worse air quality than others during the alert period. Fine particle pollution can get deep into the lungs and cause serious health problems, including heart attacks, bronchitis, asthma attacks and difficulty breathing, the alert states. Health officials say everyone can be affected, but sensitive groups face greater risk. Those groups include people with lung or heart disease, older adults, people who are pregnant, children and anyone who spends significant time outdoors. The AQMD outlined precautionary guidance based on the Air Quality Index (AQI), urging residents to check air quality levels and adjust their activity accordingly: Unhealthy for Sensitive Groups (orange): Sensitive groups should limit extended or intense outdoor activity. Unhealthy (red): Everyone may experience health impacts. Sensitive groups should avoid extended time outdoors. Very Unhealthy (purple): Sensitive groups should avoid all outdoor physical activity. Everyone else should avoid extended or intense outdoor activity. Hazardous (maroon): Everyone should avoid all outdoor physical activity. To help keep indoor air clean while pollution levels are elevated, the alert recommends several precautions. Residents should keep windows and doors closed and run an air conditioner or air purifier where possible. The alert specifically advises against using whole-house fans or swamp coolers that draw in outside air, since these systems can pull polluted air into homes rather than filtering it out. Additional sources of indoor and outdoor pollution — including fireplaces, candles, incense, grilling and gasoline-powered lawn and garden equipment — should also be avoided during the alert period, according to the NWS. The advisory does not specify particular Pasadena neighborhoods or issue separate guidance for different parts of the city; the alert applies broadly across most of Los Angeles County, with the acknowledgment that conditions may shift depending on local weather and the timing and volume of fireworks activity in a given area. Residents can monitor current and forecasted air quality conditions by visiting aqmd.gov/alertinfo, the source recommended in the alert.
Local California Context
Los Angeles County is not alone. A similar warning was issued for the National Mall in Washington, D.C., where a record-breaking 850,000 fireworks are expected to launch in 40 minutes. Nationwide, the combination of a heat dome and massive firework displays is expected to create a double dose of unhealthy air. In California, the AQMD's advisory underscores the need for residents to monitor local air quality via the South Coast AQMD Mobile App or website. July 4 and 5 are traditionally two of the worst days of the year for the region’s air quality, according to South Coast AQMD. This year’s celebration comes on the heels of a late June warehouse fire in Boyle Heights that released extraordinary amounts of soot and smoke across the county, on par with pollution generated by the previous year’s wildfires.
Areas around downtown Los Angeles, the San Gabriel Valley, and northern Orange County may see hazardous air on the evening of July 4 due to particle pollution from fireworks, according to the South Coast Air Quality Management District. Riverside County and San Bernardino could see hazardous air the next day as the particles from fireworks move east and combine with the region’s elevated levels of air pollution. The Inland Empire and most of Los Angeles and Orange counties — that is, nearly all of SoCal — may see unhealthy air at times throughout the weekend, as they do every year. Visibility in Orange County and the Inland Empire may be low Saturday night due to a soupy blend of high humidity and particle pollution.
Police officials in cities across California are using drones to cite people who use illegal fireworks over the Fourth of July weekend, adding a new enforcement dimension to the holiday. Driven by litigation from environmental advocates and opposition from the state Coastal Commission, Fourth of July fireworks shows in California are disappearing and being replaced by drones.
Conclusion
As millions celebrate the nation's 250th birthday, air quality officials urge caution. Fireworks pollution can rival wildfire smoke and linger for hours. Stay informed, stay indoors, and protect your health this July 4th weekend.