Updated Aug. 10, 2018
Editor's note: Air quality is expected to improve this weekend in the Sacramento region as we see breezier conditions, however how clear it will actually be depends on fire progress.
If you’ve stepped outside in Northern California recently, you can tell that the air quality isn't great.
More than a dozen wildfires are burning throughout the state, filling the sky with smoke and in some areas making it hazardous to be outdoors.
But how can you tell if the air quality is actually harmful? And if it is, what should you do? Here are some tips from experts about how to check air conditions and protect your health:
How do I know what the air quality is for my area?
Each day it’s smoky outside, you should check the air quality index (AQI), either at Sacramento’s Air Quality Management District website or the Environmental Protection Agency’s site, airnow.gov. That will tell you if there’s an unhealthy amount of pollution in the air where you live.
The AQI is usually calculated based on five major air pollutants: ground-level ozone, particle pollution, carbon monoxide, sulfur dioxide and nitrogen dioxide. Each is measured and weighted differently and reported on a common scale — the AQI.
In the U.S., these air quality measurements range from 0 to 500, with 500 being the most harmful. Any measurement below 100 isn’t likely to affect your health. Above that, sensitive groups may be at risk. Measurements above 300 are considered hazardous to all.
Why doesn't the AQI match what I see?
Sometimes air quality measures may not seem to match what we can see when there is heavy smoke or even ash in the air.
One reason is that smoke and haze can be visible in the air even if it's not at ground level, says Thomas Wall with the Sacramento Air Quality Managment District.
"That's one are where we see folks who look at current conditions and may see it looks OK, but it's gross looking and dark outside," Hall says. "That doesn't necessarily mean that pollution is at the ground level."
Still, Hall cautions that there can be big differences in air quality even between neighborhoods. While checking local air quality measures is a good first step, use caution if you can see or smell smoke.
"If you're smelling smoke you're definitely breathing it," Hall says. "It doesn't mean necessarily it's unhealthy, but it's a good indicator it is."
How does breathing in wildfire smoke affect your health?
Wildfire smoke contains a complex mixture of organic chemicals including carbon dioxide, carbon monoxide and hydrocarbons, plus water vapor, particles, nitrogen oxides and trace minerals. The main concern with smoke is “fine particles” — tiny bits of matter that you can inhale deeply into your lungs.
Those fine particles can affect your lungs and your heart. They irritate your respiratory system, and exposure to high concentrations can cause persistent cough, phlegm, wheezing and difficulty breathing — even for healthy people.
Studies have also found that short-term exposure to these fine particles over days or weeks can aggravate pre-existing heart and lung disease.
Are some people more affected than others?
Not everyone exposed to smoke will experience health problems. Different factors determine individual susceptibility — including your age and whether you have pre-existing lung or heart conditions, like asthma, COPD or heart disease.
Most healthy people will recover quickly from smoke exposure, but “sensitive groups” (we hear this term a lot) may experience more acute or longer lasting symptoms.
Experts say that “sensitive groups” include children, elderly people, pregnant women and anyone who has a pre-existing heart or lung disease.
What should “sensitive” people do when the air quality is poor?
If the air quality near you is poor, stay inside with the doors and windows closed and limit your physical activity. During exercise, your air intake increases, which brings more pollution deep into the lungs. Experts say staying inside and reducing physical activity can reduce exposure by at least a third or more.
You can also upgrade your air conditioner filters, or buy a portable air cleaner. If you have a central air conditioning system in your home, set it to re-circulate or close outdoor air intakes to avoid drawing in smoky outdoor air.
Other options to get a break from the smoke include going to public libraries, hospitals, movie theaters and other public buildings with good HVAC systems. If conditions are going to be bad for a long time, you might consider going to stay with a friend or family member where the air quality is better.
Masks can be helpful, but you should reduce your exposure in other ways first — namely by reducing activity and staying indoors.