How Do You Know if You Have Poor Indoor Air Quality?

Summertime is the best time to get outside and experience nature by swimming, gardening, and watching the clouds. However, the summer months are also notoriously humid and hot, causing many of us to spend a lot of time indoors in the AC. Can the heavy heat and humidity impact your home’s air quality, and will you be able to tell if your home’s air quality becomes dangerous? 

You’ll know you have poor indoor air quality if you are experiencing certain physical symptoms. If you or your housemates have difficulties breathing or other symptoms, it can indicate poor air quality. The presence of mold or dirty air can also signify poor air quality. 

If you’re concerned about the health and well-being of yourself and your family, then you’ve come to the right place. Keep reading to learn about all the tell-tale signs of poor air quality and what you can do about it! 

1. Sneezing and Cold Symptoms

One of the most common signs of poor air quality is insistent sneezing, coughing, and other cold or flu symptoms. If your home has poor air quality, it is very likely that you will begin to feel like you have caught a cold.

When your home’s air is stagnant, poorly filtered, and carrying pollutants, it can manifest in respiratory issues. These toxins and bacteria may also settle in your lungs and lead to colds and flues. 

Some air filters and purifiers work to remove these toxins and prevent the spread of germs that can cause colds and flues. Whether they’re part of a symptomatic response or an actual cold or flu, cold symptoms are signs that you have poor air quality. 

Read: 3 Ways How To Improve Air Quality In The Basement?

2. Shortness of Breath

Poor air quality causes pollutants such as dust, fungus, and mold spores to accumulate in the air. Since there is little ventilation in the house, these spores and contaminants tend to stick around and build up over time. 

An obvious indication of these pollutants is dust building up near air conditioning vents. Mold developing in the corners of your home or on the upper parts of walls is also a clear sign. 

If you see these indications accompanied by physical signs such as shortness of breath, your air quality is probably poor. As you breathe, mold and fungal spores accumulate in the lungs and inhibit airflow. This can be dangerous, especially with prolonged exposure.

3. Nausea and Digestive Issues

Sometimes poor ventilation can lead to digestive issues or discomfort. This can manifest as vomiting, diarrhea, or dizziness. 

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These symptoms are usually caused by carbon monoxide (CO) or other chemical pollutants in the air. The Centers for Disease Control and Prevention (CDC) advises people to take these symptoms seriously—CO poisoning can cause severe damage to vital organs. 

Prolonged exposure to carbon monoxide can lead to liver and kidney failure or cardiovascular failure. In some cases where an individual is sleeping, drunk, or otherwise incapacitated, they can die of CO inhalation. 

Read: Why Is Indoor Air Quality Important?

4. Asthma Attacks

Asthma is an inflammatory disease that constricts the airways of those who suffer from it. People with asthma often experience itchiness in the throat, difficulty breathing, and wheezing when exposed to triggers. 

Most experts believe poor air quality in the home and surrounding area are common triggers. This can include mold, fungal spores, chemical contaminants, and lung dust or dirt buildup. 

Air quality is crucial in preventing and managing asthma. If several family members have been diagnosed with asthma or are experiencing acute symptoms, check your air quality. Poor air quality can trigger severe asthmatic attacks, harming or potentially killing those suffering from the disorder.

5. Bad or Unpleasant Smells

Rancid, moldy, mildewy, or unpleasant smells are prime indicators of air pollution and poor air quality. However, not all smells or scents indicate contamination or harmful substances. 

The U.S. Environmental Protection Agency (EPA) dives into distinguishing and separating a foul smell from a harmful smell. Some harmful contaminants, such as carbon monoxide, have no scent. Although, certain scents are dangerous and should be addressed right away. 

The EPA advises people to check for secondary signs before concluding that a scent is harmful. Some of these secondary signs include: 

  • Moldy smells 
  • A damp or moist atmosphere
  • Heavy or foggy air 
  • Mold and fungal spores 
  • High humidity 
  • Indoor or nearby machinery leaking fumes
  • Heavy traffic with poor ventilation 

Chemical contamination is highly probable if you live in the city or other heavily congested areas. You’ll want a better ventilation system if you smell car or gas fumes in your home. 

An improved ventilation system can best address musty smells. Basements and other dark and poorly ventilated spaces are the most likely candidates for mold buildup. Consider installing a basement ventilation system to address your mold and fungal buildup issues. 

6. Irritated Eyes and/or Nose

While cold and flu symptoms are among the most common indicators of poor air quality, allergy symptoms are a close second. Itchiness and irritation around the eyes and nose could indicate the presence of irritants in the air. 

Allergy symptoms such as itchy eyes and nose and redness around the eyes are common symptoms of air pollutants. These symptoms are not usually severe, but they are annoying and indicate the presence of dust mites and pollen. 

7. Testing and Treating Air Quality Concerns

Testing your air quality is a great way to narrow down the causes of your indoor environmental pollutants. Depending upon the severity of the air contaminants, the solution can be as simple as opening windows or as complex as ionizing the air. 

Many AC and ventilation systems come with built-in ionizers. You can check out our post on AC unit ionizers to dive deep into the benefits of these units! 

In short, however, these units remove contaminants and neutralize ions in the air. This improves the quality of sleep, mood, and overall health. 

Read: What Affects Indoor Air Quality?

Can Poor Air Quality Harm You?

Poor indoor air quality can harm you. Short-term or minor air pollution can cause respiratory issues and eye and nose irritation. Long-term exposure can deplete blood oxygen levels, damage the lungs, and cause severe diseases like COPD or asthma

Indoor air quality is essential to longevity, quality of life, and prevention of chronic diseases. According to the March of Dimes, air pollution exposure during pregnancy can negatively impact a baby’s life. 

This includes inducing premature birth and underweight birth in infants. These birth factors are prime indicators of future chronic disorders, such as asthma and organ development.

However, poor air quality can also cause the following complications: 

  • COPD
  • Impact Cardiovascular health
  • Lung damage
  • Constrict airways 
  • Damage organs 
  • Chronic headaches or migraines
  • Poisoning 
  • Liver failure 
  • Kidney damage 

Many people suffering from long-term carbon monoxide exposure must endure dialysis. Others who experience long-term toxic exposure may develop COPD and other heart health issues. 

You can learn more about the importance of air quality in my article outlining why indoor air quality is important.


Air pollution can be a complicated issue to think about. Sometimes it is obvious and manifests as moldy smells and fungal spores. Other times, it’s very subtle and takes time to identify. 

The best way to protect your family and yourself is to ensure your ventilation systems are clean and functioning. For this reason, the EPA recommends cleaning your air ducts as needed. 

If you are experiencing any of the above symptoms, call your AC technician to check your units. A functioning, clean unit can make all the difference you need to breathe well again.