The Importance of Indoor Air Quality During Flu Season

Scott Peck | Jan 15 2026 16:00

Indoor air quality (IAQ) is crucial for maintaining health, especially during flu season. With most people spending about 90% of their time indoors, per the U.S. Environmental Protection Agency (EPA), understanding IAQ is vital. Indoor pollutant levels can be significantly higher than outdoor levels, which influences illness spread and recovery during flu season.

Sources of Indoor Pollutants

Indoor pollutants come from various sources. Biological contaminants like viruses, mold spores, and pet dander are prevalent, along with chemical pollutants like carbon monoxide and VOCs from household products. Everyday activities such as cooking and heating can also stir up particles, which remain unless properly ventilated or filtered.

Health Effects of Poor Air Quality

Inhaling polluted air can cause everything from eye irritation to serious long-term health issues like heart disease and cancer. During cold months, when people are indoors more, poor air quality can exacerbate flu symptoms or make viral infections more likely. Particles can inflame the respiratory system, lowering defenses against viruses.

The Value of Air Quality Testing

Testing indoor air quality helps identify pollutants you're exposed to daily. It measures levels of substances like mold and VOCs, helping homeowners take steps to improve IAQ. Knowing specific pollutant levels allows targeted actions, like addressing mold, which is a common respiratory irritant.

Importance of Checking Filters

HVAC filters are the first defense against airborne pollutants. When clogged, they lose efficiency and let contaminants spread. Regularly checking and replacing filters keeps HVAC systems efficient and air clean, typically needing attention every one to three months, depending on usage and household factors.

Significance of Duct Cleaning

Dust, allergens, and mold can accumulate in air ducts, spreading throughout the home. Regular duct cleaning is crucial, especially if there are visible signs of dust or mold. Clean ducts lead to healthier air and a more efficient HVAC system.

Managing Indoor Humidity

Humidity affects IAQ significantly. Keeping humidity between 30-50% prevents mold growth and keeps viruses at bay. Humidifiers and dehumidifiers can help maintain balance, reducing biological pollutant growth and improving comfort.

Considering Air Purification

Air purifiers capture particles that slip through regular filters. HEPA filters in purifiers effectively trap small particles like allergens. While not a substitute for ventilation and maintenance, purifiers contribute to cleaner air.

The Role of Ventilation

Ventilation dilutes indoor pollutants and helps keep the air fresh. It is crucial for respiratory health as it removes contaminants. Improving ventilation through HVAC settings or opening windows reduces the spread of flu, as viruses linger longer in poorly ventilated spaces.

Simple Practices for Better Air Quality

You can enhance indoor air quality with simple habits:

  • Avoid smoking indoors to keep the air clean.
  • Use exhaust fans during cooking.
  • Opt for gentle cleaning products.
  • Vacuum with a HEPA filter to capture dust.

Flu season underlines the importance of clean air. Enhancing IAQ helps decrease virus transmission and chronic respiratory problems. Testing air quality, maintaining filters, ensuring proper ventilation, and managing humidity all contribute to a healthier living space.