DELAWARE — Air quality remains unhealthy across Delaware County on Friday as smoke from Canadian wildfires continues to blanket central Ohio, prompting health advisories, facility closures and warnings to limit time outdoors.
The Delaware Public Health District reported the county’s Air Quality Index reached 489 as of 8 a.m. Friday morning — well into the “Hazardous” category on the Environmental Protection Agency’s air quality scale.
Air quality reaches the “Hazardous” category when the Air Quality Index exceeds 300.
At that level, Delaware Public Health recommends everyone avoid physical activity outdoors. Sensitive groups — including children, older adults, pregnant women and people with heart or lung disease — should remain indoors and keep activity levels low whenever possible.
The smoky conditions have already prompted closures across Delaware County.
The City of Delaware closed Jack Florence Pool and the recreation gym for Friday, while keeping the recreation center open for restroom access only.
Olentangy Caverns has also closed its petting zoo for the day, citing the health and safety of its staff and animals, though the attraction’s other activities remained open.
What is particle pollution?
The smoke blanketing central Ohio contains tiny particles known as particulate matter, or PM. Many of the smallest particles — known as PM2.5 — are produced by wildfires and are small enough to travel deep into the lungs.
PM2.5 refers to particles smaller than 2.5 micrometers in diameter — about 30 times smaller than the width of a human hair — which is why they can penetrate so deeply into the body.
Some can even enter the bloodstream, increasing the risk of respiratory and cardiovascular problems.
According to the U.S. Environmental Protection Agency, exposure to particle pollution has been linked to coughing, wheezing, reduced lung function, asthma attacks, heart attacks, strokes and premature death in people with heart or lung disease.
People with asthma, COPD and heart disease face the greatest risk, but children, older adults, pregnant women and outdoor workers are also considered especially vulnerable to particle pollution.
How to protect yourself
Health officials recommend everyone limit prolonged or strenuous outdoor activity while the alert remains in effect.
This applies to everyone, but especially people with asthma, chronic obstructive pulmonary disease, heart disease and other respiratory conditions. Children, older adults, pregnant women and outdoor workers are also considered especially vulnerable.
Residents should watch for symptoms including coughing, wheezing, chest tightness, shortness of breath, dizziness, or irritation of the eyes, nose and throat.
To reduce exposure, officials recommend:
- Staying indoors as much as possible.
- Keeping windows and doors closed.
- Running air conditioning on its recirculation setting when available.
- Shortening, rescheduling or reducing the intensity of outdoor activities.
- Avoiding indoor activities that create additional smoke or particles, including burning candles or using wood-burning fireplaces.
Air quality alerts statewide
The National Weather Service said smoke from Canadian wildfires is expected to keep fine particle pollution at unhealthy levels throughout Friday.
The Ohio Environmental Protection Agency also issued a statewide Air Quality Advisory. Conditions across the state were expected to range from “Unhealthy for Sensitive Groups” in southwestern Ohio to “Unhealthy” throughout the rest of the state, with hourly concentrations potentially reaching “Very Unhealthy” or “Hazardous” levels.
The Mid-Ohio Regional Planning Commission issued an Air Quality Alert through midnight Friday for Delaware, Franklin, Licking and Fairfield counties.
MORPC forecast an AQI of 179 for particulate matter Friday, which falls within the “Unhealthy” category. The agency said light winds would recirculate dense smoke across central Ohio, while pollution carried over from Thursday and a morning temperature inversion would trap smoke near the surface.
Afternoon showers and thunderstorms may help disperse some of the smoke, but are not expected to prevent unhealthy conditions.
Why is smoke from Canada reaching Ohio?
The hazy skies over Delaware County and the rest of the country are the result of hundreds of wildfires burning across Canada.
As of Friday, Canadian officials reported 893 active wildfires nationwide, including 127 burning out of control, with nearly 2.8 million hectares — about 6.9 million acres — burned so far this year.
Weather patterns have carried smoke from those fires hundreds of miles into the Midwest and Great Lakes region, reducing visibility and pushing fine particle pollution to unhealthy levels across much of Ohio.
Environment and Climate Change Canada has warned that above-average temperatures and dry conditions are expected to keep wildfire danger elevated across parts of the country through the summer, particularly in northern Manitoba, Ontario, Quebec and the territories.
