Thursday's massive Colby Fire, burning in the foothills above Glendora and Asuza, has sent up a plume of toxic smoke that can be seen practically from the Pacific coastline.
Even if your home is not in the path of the fire, you can still be affected by smoke particles released into the air, experts say.
What's in that smoke, and how much should you be worried about breathing today?
Depending on the fire, the smoke can be made up of various substances including carbon dioxide, carbon monoxide, water vapor, particulate matter, organic chemicals, nitrogen oxides and more. Exposure to smoke can cause a range of health effects, from eye and lung irritation to asthma and premature death.
Particulate matter is the main public health threat during short-term exposure to wildfire smoke, so it’s crucial to protect yourself.
“Really it's about common sense,” said Philip Fine of the South Coast Air Quality Management District on AirTalk Thursday. “If you can see the smoke, if you can smell the smoke, you can tell when the particulate matter levels are really high. If you can do that, you should exercise caution.”
Here are tips on how to stay safe if you're in the patch of a wildfire from the AQMD and the Air Resources Board:
What should I do if I’m in an area affected by smoke?
Stay indoors; close all doors and windows. Everyone should avoid vigorous outdoor and indoor activity. Those with respiratory difficulties or heart problems, as well as the elderly and young children should all remain indoors. Keep windows closed and run your air conditioner if possible. Running an indoor air filter is effective in helping reduce the amount of polluted air inside the home. Do not use any indoor or outdoor wood-burning appliances or fireplaces. When smoke subsides, you should air out your home to clear any polluted air that might be trapped inside.
What if I don’t have air conditioning, and it’s too hot to stay inside?
Heat can be dangerous to anyone, but especially the elderly and very young. If you rely on open windows and doors for cooling, AQMD recommends you stay with friends or family, or head to a clean air shelter.
What if I have to be outside?
The best thing to do is to seek shelter, but if you must be outside, being prepared is key. Wearing a special N95 or P100 respirator mask can help protect you against the fine particles in smoke. Paper or surgical masks are not effective in preventing inhalation of smoke.
Who is the most vulnerable to smoke exposure?
Most healthy people will recover quickly if exposed to smoke, but there’s a large number of people who should take extra precaution. People with asthma and those with cardiovascular or respiratory diseases can experience worsening of their conditions if they inhale smoke. The elderly, young children and pregnant women are all sensitive populations that should avoid exposure. In addition, smokers should beware, because they may not feel symptoms of exposure as acutely as non-smokers.
What if I’m driving through an area affected by smoke?
A car should only be used to leave an area, not as shelter. If you’re in a car, close windows and doors and run your car’s air conditioner, making sure you’re circulating the air already in the car and not pulling in fresh/smoky air. However, according to the AQMD, carbon dioxide levels can spike quickly in newer cars if vents and windows are closed and the circulation setting is on. It’s a good idea to crack the windows once you're in there for a while to prevent grogginess.
How do I find out if I'm in an advisory zone?
The AQMD monitors the air 24/7 and offers a handy, interactive map of air quality in Southern California. You can check the air quality in your area at any time via their website. They will also post information there if there's a special advisory because of a wildfire or other event. You can also sign up for advisory alerts here.