Why is the air quality bad today? 'Very unhealthy' air quality in Oklahoma City

Sensitive groups in Oklahoma City should avoid outside activities today as the metro is experiencing "very unhealthy" air quality.

According to the U.S. Environmental Protection Agency, air quality indexes indicate how polluted the air is, or forecast how polluted it could become. Government agencies use these indexes to measure public health risks and communicate any dangers to the public.

The U.S. air quality index looks at five pollutants regulated under the Clean Air Act: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide, the EPA reports.

When there's an increase in a type of pollutant, the AQI will increase. For example, AQI can increase during rush hour traffic when there's an increase in air pollutants, or when winds blow smoke from wildfires into an area.

Why is the air quality bad today?

According to Accuweather, Oklahoma City had unhealthy levels of PM 2.5 and PM 10 pollutants as of Monday morning.

Accuweather warns that health effects will be immediately felt by sensitive groups and should avoid outdoor activity.

People without sensitivities are likely to experience difficulty breathing and throat irritation.

What are PM2.5, PM10 pollutants?

Airborne particulate matter, or PM, is a mixture of solids and aerosols composed of small droplets of liquid, dry solid fragments and solid cores with liquid coatings, according to the California Air Resources Board.

Scientists track two main types of particulate matter that are inhaleable. Both pollutants often derive from different emission sources, like the combustion of gasoline, oil diesel fuel or wood produce.

• PM10: Particles 10 microns or less in diameter. This can also include dust from construction sites, landfills and agriculture, wildfires and waste burning, industrial sources, wind-blown dust from open lands, pollen and fragments of bacteria.

• PM2.5: Particles that are 2.5 microns or less in diameter, which is a smaller portion of PM10.

What happens if I'm exposed to PM2.5, PM10 pollutants?

According to the California Air Resources Board, short-term exposures of PM2.5 pollutants have been associated with premature mortality, increased hospital admissions for heart or lung causes, acute and chronic bronchitis, asthma attacks, emergency room visits, respiratory symptoms and restricted activity days.

Usually, these health effects have been reported in infants, children and older adults with preexisting heart or lung diseases.

Short-term exposures to PM10 have been associated with worsening of respiratory diseases, including asthma and chronic obstructive pulmonary disease, leading to hospitalization and emergency department visits.

This article originally appeared on Oklahoman: Why is the air quality bad today in OKC? What does air quality mean?