All You Need to Know about Ventilation Testing

Your indoor air may not be highly polluted, but air pollutants can build over time in your surroundings if enough fresh air does not enter your home or indoor air does not leave the building.

Indoor air quality is very important for your health because you spend most of your time indoors. Exposure to higher concentrations of pollutants can risk your and your family members' health. It can also cause structural damage to the building.

This is where ventilation testing comes to help. It tells you about indoor air quality and how you can improve it to prevent its damaging effects.

Read the article to learn about ventilation, its types, ventilation testing, how it is done, and much more.

What is Ventilation?

Like your lungs, your home or any other building also needs fresh air to survive; otherwise, molds, fungus, and other harmful elements can grow in it and damage its structure in different ways.

Ventilation is the introduction of fresh outdoor air that dilutes indoor air pollutants and makes the air healthy for you and your home. It provides a way to get rid of allergens, dust, toxic gases, and moisture.

Importance of Ventilation

Insufficient exchange of indoor and outdoor air leads to poor ventilation and accumulation of pollutants. That is why you should keep your ventilation system working properly to maintain a healthy environment.

Good ventilation can help you:

  • Prevent humidity
  • Remove unpleasant smell and cooking odor
  • Give air to fuel-burning appliances
  • Remove biological and chemical contaminants

Contaminants That Build Up with Poor Ventilation

Humans release carbon dioxide (CO2) gas when they exhale. It is also produced when fuel is burnt. Although a certain amount of CO2 is always available in the indoor air and it is harmless, this harmless gas can turn into harmful gas if it is not circulated and builds up in buildings in higher concentrations.

Many other gases are produced from combustion appliances such as stoves and water heaters. Examples of some of these gases include carbon monoxide, nitrogen oxide, nitrogen dioxide, etc. They can be highly toxic and can cause bad health effects if they are not removed from your surroundings on time.

Excessive moisture can build up in your home due to poor ventilation. It can increase humidity and make you feel suffocated. Additionally, it can support mold growth and lead to insulation damage. It can reduce the performance of your cooling equipment as well.

Biological pollutants such as germs, allergens, and animal dander can also accumulate in a poorly ventilated building. They can produce ill-effects and deteriorate your health condition if you already have a respiratory disease.

Signs of Poor Ventilation

Here are the common signs that indicate your home has poor or insufficient ventilation.

  • You experience shortness of breath and fatigue due to low oxygen levels.
  • A foul odor lingers in your home due to low air movement.
  • The humidity level is gradually increasing in your home and damaging walls (peeling wall paint).
  • There are black or green spots on walls or wooden furniture. They indicate mold growth. The affected area has a musty smell.
  • You develop headaches soon after entering your home.
  • You often feel dizzy and nauseous.
  • If you have a respiratory disease like asthma, you feel your health is declining further even when you are not doing anything to deteriorate it.
  • You feel health-related symptoms only when you are inside the building. Your symptoms improve when you leave the building.

What are Different Types of Ventilation?

There are different kinds of ventilation. We have provided a brief introduction to three common types of ventilation.

Natural ventilation

It is the uncontrolled movement of fresh air through doors, windows, and roofs without any mechanical assistance. It used to be the most popular form of ventilation, but now it has been replaced by controlled ventilation. You may still find it in older homes.

Spot ventilation

It is a form of ventilation that involves the usage of localized tools like exhaust fans, hoods, etc., to exchange air. It is usually used with natural ventilation to improve its performance.

Whole-house ventilation

As the name indicates, it is a form of controlled ventilation in which a dust system or fans are used to exchange indoor and outdoor air.

What does Ventilation Have to Do with Indoor Air Quality?

Various chemicals and pollutants enter the indoor air due to human activities. They are harmless up to a certain level. When that level is crossed, the pollutants can negatively impact your health and damage your building. Getting rid of them is crucial to restoring indoor air quality; otherwise, the air quality will worsen with time.

Ventilation is the only way to remove these pollutants and bring in fresh air. When the performance of your ventilation system declines, your indoor air quality will also decrease.

HVAC System Performance and Ventilation

HVAC (heating, ventilating, and air conditioning) systems are installed in homes to control their air quality, temperature, and moisture levels. You might already know that the 'V' in HVAC is for ventilation. It consists of different components such as ducts, air handlers, supply vents, and return vents.

It generally has two vents that balance air circulation. Supply vents bring in clean air while return vents filter stale and polluted air to remove all sorts of contaminants from it.

The indoor air quality declines when your HVAC system does not work properly. The system fails to properly filter and circulate air throughout a home. Therefore, if you want to improve ventilation in your home, make sure your HVAC system works efficiently.

Ventilation Testing

Ventilation testing is performed to test the performance of ventilation system components such as extractor fans. It is tested how much air they extract to promote air circulation in a home. It is performed with the help of different instruments that measure the number of air pollutants like TVOCs (total volatile organic compounds), gas, etc.

Why is Ventilation Testing Important?

A ventilation test can help you figure out different problems. For instance, if you are having more asthma attacks or allergy episodes, having a ventilation test can help you figure out how your home's air quality is influencing your health.

It ensures you live in a healthy environment where there are only a few air pollutants around you, and their level is also low in the air.

As an employer, it is your responsibility to provide your workers with a clean environment to work in. Ventilation testing can help ensure your offices have sufficient oxygen and low pollutant levels. It will reduce the risk of your employees falling ill and increase their productivity.

How Do We Test for Ventilation?

Ventilation testing should be done by qualified and certified indoor air quality inspectors. At IAQ Environmental, we use efficient techniques and tools to check contaminant levels in indoor air.

We conduct a floor-by-floor walkthrough of the building and take measurements in every room, including bathrooms, kitchens, bedrooms, etc. We determine levels of air pollutants such as particulate matter (PM), gas, and TVOC.

In addition, we also check the performance of your HVAC system to see if it is extracting the right amount of air.

We deduce a conclusion based on our observations and test results. We provide a report and suggest the best possible solutions to resolve the issue and restore your indoor air quality.


How long does ventilation test take?

A ventilation test can take hours to days, depending on the size of your building and the number of ventilation units. If you want to have this test sooner, it is best to contact the indoor air quality inspector and state your problem beforehand.

When should you have a ventilation test?

If you suspect your indoor air quality is declining due to the poor performance of your ventilation system, it is high time to have a ventilation test. You can also have this test to check the performance of your newly installed ventilation unit.

What are the risks associated with poor ventilation?

Poor ventilation can damage your health and building in numerous ways.

  • The concentration of carbon monoxide can build up. This gas is odorless and colorless, meaning you cannot detect it in the air on your own. Its high concentrations can kill a person in a few minutes.
  • The radon concentration can increase and lead to lung cancer if not checked on time.
  • High humidity increases the risk of mold growth, leading to high maintenance costs.
  • High humidity reduces the cooling system's performance, leading to high electricity bills.


Good ventilation in your home, office, school, or any sort of building is important for the health of its occupants. It reduces exposure to indoor air pollutants, stops condensation, and regulates air circulation.

You should let the fresh air come in through doors and windows if the concentration of outdoor pollutants is comparatively low. Install an HVAC system, exhaust fans, air filters, and similar beneficial tools that can help you boost air quality.

Don't know if your ventilation system is working effectively or not? Hire IAQ Environmental and let its experts measure your indoor air quality, identify ventilation issues, and provide the best solutions for good ventilation!

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