Our Complete Guide to Indoor Air Quality [Free Guide] 

Good indoor air quality is important for everyone. These days we spend more and more time indoors.

Our environment has a direct impact on our health and well-being. Yet, many people don’t know how to tell if the air they’re breathing is good or bad.

Here, you’ll learn about indoor air quality and why it matters so much. You’ll also find out what you can do to improve the air inside your home.

For our complete indoor air quality guide, keep reading.

What Is Indoor Air Quality? 

As implied by its name, air quality is the quality of air inside your home. The air quality of your home can affect your comfort considerably. More importantly, it can have a massive impact on your health.

In some cases, you can feel the effects of poor air quality immediately. For instance, you may notice your allergies acting up if the air quality in your home is poor.

However, other symptoms of poor air quality may take years to develop. Over time, poor air quality can result in respiratory issues, heart disease—and even cancer.

Fortunately, air cleaning, filtration, and proper ventilation can help. Without these measures, indoor pollutants in your home can reach unhealthy levels.

Still, some indoor air contaminants are unavoidable. You’ll need a way to filter and transfer them out of your home.

Also, high temperature and humidity can cause contaminants to become more concentrated. A comfortable environment is more than convenient—it directly correlates with the quality of your health.

Possible Air Quality Issues 

A top reason for poor indoor air quality is poor ventilation. Usually, you’d experience this kind of problem if you’re having issues with your ductwork.

Indoor air pollution can also build up due to combustion sources. These sources might include:

• Coal
• Gas
• Oil
• Wood burning appliances

Pollutants can also build up in building materials. The insulation in your home can trap contaminants that can contribute to poor air quality. You could also unintentionally introduce toxins to your indoor air with the regular use of everyday cleaning products.

Dust On Womans Finger

The Top Threats to Your Air

There are a few threats to indoor air quality that everyone should avoid. It’s important to have an awareness of airborne contaminants.

Things that you use every day can affect your health. In fact, many of them are leading environmental health hazards.

Some pollutants are even two to three times more concentrated indoors than they are outdoors. The following entries highlight a few of these threats.


Allergens are airborne contaminants that trigger asthma symptoms. These contaminants might include dust mites.

Pet dander can also serve as an allergen. Likewise, mold on your shower curtain can trigger allergic symptoms.

What’s more, allergens can build up on infrequently washed blankets. The same applies to your kids’ favorite stuffed animals.

In some cases, asthma symptoms might present as a cough, chest tightness, or wheezing. In extreme cases, however, these symptoms can prove life-threatening.

In part, proper medication can help to control asthma symptoms. However, it’s equally as important to control the things that you breathe in your air.

The following entries offer examples of contaminants that are beneficial to reduce or eliminate.


Asbestos is a naturally occurring mineral fiber. It was once a popular material until researchers discovered how dangerous it is for humans.

Still, asbestos remains in many materials to this day. These materials include:

• Car brakes
• Ceilings
• Cement
• Coatings
• Floor tiles
• Heat resistant materials
• Packaging
• Roof shingles

If you live in an older home, builders may have used asbestos in part of its construction. Still, don’t panic just yet.

Usually, you won’t contaminate your air with asbestos building materials until you go to remodel or fix something. If you damage the surface of asbestos building materials, you can release asbestos particles into the air. This is when they become dangerous.

If you inhale asbestos particles, they can cause scarring in the lungs. This condition is called asbestosis.

Asbestosis can cause breathing problems. It can also lead to heart failure or even lung cancer.

Cigarette Smoke

Secondhand tobacco smoke also contributes to poor indoor quality. It can affect the health of people who don’t smoke. It’s especially dangerous for children.

In addition, secondhand smoke aggravates symptoms of asthma. Research has shown that it can also increase the risk of ear infections as well as sudden infant death syndrome.

Secondhand smoke gets released into the air when people smoke cigars, cigarettes, and pipes. Smokers also release it into the air when they exhale.


Like secondhand smoke, particles and gases come from burning materials. This kind of indoor air pollution can come from:

• Chimneys
• Dryers
• Fireplaces
• Gas
• Water heaters
• Wood-burning stoves

Many of these home features can produce carbon monoxide. It’s a colorless and odorless gas. Carbon monoxide impairs the body’s ability to deliver oxygen.

Nitrous oxide is another dangerous and undetectable gas. This compound can cause eye, nose, and throat irritation. It can also lead to a respiratory infection.


Formaldehyde is a type of VOC. It’s another dangerous compound that you may find in building materials.

For instance, formaldehyde might present in chemicals used to clean air. You may also find formaldehyde in some wood products. Also, you could accidentally introduce formaldehyde into your home as a byproduct of other gaseous pollutants.

Unlike carbon monoxide and nitrous oxide, however, formaldehyde has a strong smell. Also, it’s extremely irritating to your lungs. Even worse, formaldehyde can affect your nervous system.

In children, formaldehyde can trigger asthma symptoms. In fact, it can prove extremely poisonous for children with developing bodies.


Again, if you live in an older home, it’s possible that there’s lead in your paint. As with asbestos, lead particles usually will not get into the air until you do renovation work.

This work might include scraping or sanding. By disturbing the surface of lead-based paint, you’ll release lead into the air. However, lead can also originate from contaminated drinking water and soil.

Lead is especially dangerous for babies and young children. Their young bodies are especially susceptible to neurological damage.

Furthermore, babies and kids love putting their hands in their mouths after touching all kinds of surfaces and picking up strange things. If you have lead paint in your home, children are also more likely to face lead poisoning for this reason.


If you have mold in your home, that doesn’t mean that you’re a bad housekeeper. Mold spores are in the air all the time. However, they’ll land, attach and grow on warm moist surfaces.

Some mold spores, however, will enter your airways. When they do, they can cause unwanted symptoms.

These symptoms can include a runny nose, red eyes, and sneezing. You may also experience other hay fever-like symptoms if you’re exposed to mold spores.

Some people get a rash if they even touch the mold. With mold, it helps to reduce and eliminate moisture.


Nobody likes bugs in their home. However, the same chemicals we count on to keep bugs out of our homes can pollute our indoor air.

The active ingredients of pesticides can prove bad for our health. They often contain microorganisms. These microorganisms may include bacteria, fungi, and viruses.

Pesticides may also have dangerous inert ingredients. Still, they’re toxic to humans.

They’re called volatile organic compounds (VOCs). VOCs might help the active ingredient of a pesticide penetrate a surface.

They may also prevent a product from caking or foaming. In addition, a manufacturer might use a VOC to extend the shelf life of a pesticide product.


Radon is a naturally occurring radioactive gas. It’s found in soil and can get inside your home. It might enter through a crack in the floor or one in a wall near the ground. You may also find radon in drinking water.

It’s the leading cause of lung cancer among non-smokers when spread in the air. It’s also the second leading cause of lung cancer among both groups. You can get rid of radon by installing improved ventilation.

Volatile Organic Compounds (VOCs) 

Pesticides and formaldehyde aren’t the only VOCs. Other VOCs can release into the air during evaporation, product use, or storage.

Unfortunately, several common household cleaning products contain VOCs. These products may include:

• Aerosol spray
• Air freshener
• Chlorine bleach
• Detergent
• Paint
• Rug cleaner
• Varnish

If you’re exposed to a VOC, you may experience eye, nose, and throat irritation. You can also experience headaches and nausea.

Exposure to a VOC can also cause liver, kidney, and neurological damage. It could even lead to cancer in some instances.

Indoor Air Quality Standards

Clean Air Woman In Yellow Arm Chair

Let’s start thinking about what you can do to protect the quality of air in your home.

Every home is different. They come in all configurations, shapes, and sizes.

It seems like there are building codes for just about everything when it comes to your home. According to building codes, your home must provide shelter and comfort.

It must also fulfill several functional requirements. Your home must comply with applicable codes and standards to fulfill these objectives.

One of those codes and standards is indoor air quality (IAQ). The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) establishes indoor air quality standards.

Builders must comply with codes established by a consensus of leaders in the organization. The ASHRAE air quality standards provide builders with the minimum requirements for safe indoor air quality.

Interpreting ASHRAE Air Standards

The ASHRAE standards for indoor air quality is a massive volume of text. However, there are a few key takeaways from ASHRAE standards that you should know.

For example, you’ll want to think about how the furnishings, appliances and equipment that you buy contribute to indoor air quality. You also want to consider the activities that you perform in your home.

It’s also important to think about indoor air quality when you buy certain products. These products might include those for:

• Cleaning
• Maintenance
• Personal care
• Pest control

You also want to consider how your daily activities contribute to IAQ. Thinking about how you perform simple tasks such as bathing and cooking can help to improve the quality of air in your home.

However, there’s an overarching theme that you must consider when it comes to indoor air quality. Modern homes are sealed much tighter than older homes to promote energy efficiency.

As a result, you can’t count on them to naturally ventilate air like older homes. The contaminants we produce in our homes get trapped inside. Now, the things that we do in our homes are more important than ever before.

It’s important to have some type of mechanical ventilation in your home. This kind of installation might include exhaust fans in your kitchen and bath.

How to Control Your Indoor Air Quality

The good news is that you can control air pollution in your home. For example, you’ll want to consider how the performance of your HVAC system impacts the quality of air in your house.

You also need to maintain your HVAC system and change the filters regularly. These kinds of straightforward practices will reduce bacterial spores, dust, pollen and mold in your home.

Also, you’ll need to understand that the things that settle in your air ducts get recirculated into your air. You may also want to consider duct cleaning for this reason.

Most people don’t have the equipment or training to clean ducts properly. Fortunately, a skilled HVAC professional can get the job done effectively.

It’s an excellent idea to schedule routine maintenance performed by a trained HVAC technician. By doing so, you can ensure that the air inside your home stays healthy.

Meanwhile, here are a few things that you can do to make sure that the air in your home is safe.

Testing for Radon

You can test for radon with a do-it-yourself kit. Choose a kit that’s labeled “Meets EPA Requirements.” Alternatively, you can hire a skilled HVAC professional to perform the test for you.

In either case, you may find that there’s radiation in your air. If so, the next step is to have your water supply tested by a certified lab. This test will also help you figure out how to deal with the problem.

Establishing a Smoke-Free Zone

You can also avoid or discourage smoking if you want to improve air quality in your home. Cigarette smoke contains more than 4,000 chemicals. Forty of those chemicals are poisonous.

These chemicals produce hazards to both smokers and non-smokers. You can avoid these risks by asking smokers to smoke outside. At a minimum, you’ll want to increase ventilation in your home to decrease your exposure to secondhand smoke.

Adding Appropriate Ventilation

Again, it’s important to have exhaust fans in your bathroom and kitchen. You should also have proper ventilation for your clothes dryer.

This kind of ventilation is usually quiet. More importantly, however, it reduces moisture and organic pollutants that come from vaporized hot water.

You’ll also want to make sure that your crawlspace and attic are properly ventilated. In these areas, you want to lower the humidity and prevent water condensation.

Avoiding Chemical Inhalation

If you use household cleaning products, make sure that you read the instructions and comply with any warnings. For instance, a product label might suggest that you use it in a well-ventilated area.

These kinds of areas may include near open doors or windows or near an exhaust fan. You may even want to use chemicals solely outdoors. Also, it’s important to dispose of empty cleaning product containers or unneeded chemicals properly.

As for pesticides, you also want to follow the directions on the label. You should mix pesticides outdoors and use them only in well-ventilated areas.

You should also dispose of used pesticide containers according to the manufacturer’s or your hazardous waste collector’s guidelines. You may even want to consider non-chemical methods of pest control.

Other Air-Quality Threats

You also want to reduce your exposure to biological contaminants. For instance, you want to keep air humidifiers properly cleaned.

It’s also important to thoroughly clean and dry water-damaged carpets. In fact, it’s important to clean your entire home regularly. By doing so, you can reduce the contaminants and allergens present in your home.

You may use a kerosene or gas space heater. If so, make sure that you follow the manufacturer’s recommendation for use. Also, use the right fuel for your equipment.

Watch out for yellow tip flames using your heater. This kind of flame could mean an emission of increased pollutants.

In addition, use an exhaust fan over your stove or range. If you use a wood-burning stove, make sure that it’s the right size and it’s EPA certified.

Fighting Back Against Poor Air Quality

Man Enjoying Clean Air

We can’t overemphasize the importance of proper ventilation in your home. Also, your ventilation system must work consistently.

For instance, your stove may only emit carbon dioxide while it’s in use. However, other sources can emit pollutants into your home continuously.

These sources could include air fresheners, building materials or furnaces. They could also include solvents for cleaning and hobbies.

You can even pollute your air with paint strippers and pesticides. Even worse, these kinds of chemicals remain in the air for a long time. As a result, it’s important to address ventilation no matter the size or shape of your home.

Is My Indoor Air Quality Good?

The first step in figuring out if you have good indoor air quality is identifying a specific problem. For example, you may have developed troubling symptoms.

These symptoms may have started after you moved into a new home. Alternatively, they may have begun after you brought new furniture home. You may even start to exhibit poor health after treating your home with a pesticide.

You’ll need to think about these kinds of potential sources of pollution. They come from your air, furnishings or products that you’ve used in your home.

Remember that these items may not have necessarily caused the problem. Still, taking these kinds of facts into consideration is an important first step in assessing the air quality in your home.

How to Measure Indoor Air Quality 

Now that you’ve considered potential air contaminants, you’ll need to test for the presence of those contaminants in your home. You may have started to notice health symptoms. You may have otherwise noticed that your home has poor ventilation.

You’ll want to enlist the help of a professional if you notice these kinds of problems. A professional HVAC service has experience in measuring air pollutants and airflow.

They also have the right equipment for the job. A trained HVAC technician also knows the EPA guidelines for measuring indoor air pollutants.

Changing Your HVAC Filters

An air filtration system can improve the air quality in your home drastically. No matter the type of air filtration system, however, you must change the filters regularly.

A dirty air filter can pollute the air in your home. Even worse, it can impede airflow. Clean filters are especially important for keeping your ducts clean.

Minimum efficiency reporting value (MERV) ratings measure how efficiently filters trap airborne particles on a scale of 1 to 20. When replacing your filters, you’ll want one with a MERV of between 10 to 16 or more.

Monitoring Humidity

Excess humidity can also contribute to poor indoor air quality. What’s more, it can promote mold growth.

There’s a higher risk of mold growth if your indoor humidity is more than 50%. Ideally, you want your indoor humidity to remain between 30% and 50%.

If your home’s too humid, you can open the windows. Alternatively, you can turn on your air conditioner or invest in a dehumidifier.

Optimizing Ventilation

Opening a window or buying a fan is one of the easiest ways to improve ventilation in your home. These are great methods for ventilating VOCs from your interior.

Ventilation is also great for kitchens. A good kitchen exhaust fan will keep gases and harmful particles from becoming highly concentrated. When used in a bathroom, a fan will help to reduce water vapor lingering in the air.

However, there’s another side to ventilation. You must ensure that the air that’s being pulled into your home is dry and clean.


Weatherization reduces waste when it comes to heating and cooling your home.

Weather stripping is a great way to weatherize your home and it does not negatively affect the quality of your air. Beware of bargain caulks when installing, though, as a small number emit VOCs.

Additionally, investing in insulation is a great way to reduce your energy bills and keep polluted outdoor air from entering your home to a minimum. To be safe, you should consider hiring a contractor to insulate your walls.

You may even purchase storm windows to keep outdoor air from getting into your home.

These kinds of measures are great, but they seal your home. In other words, they can make indoor air pollutants become more concentrated. This is known as “Tight Home Syndrome.”

It’s important to recognize feelings of “stuffiness” in your home. The more you weatherize, the more you’ll want to make sure that you maintain adequate ventilation.

Going the Extra Mile for Safe Air

You need to do more than change your air filter to maintain clean air. Again, you must keep your HVAC ducts clean.

It’s also important to clean all associated HVAC components. These components might include:

• Grills
• Interior surfaces
• Registers

Not everyone is comfortable with cleaning their HVAC system, and that’s fine. An expert HVAC technician will make sure that the air in your home is safe for you and your family.

HVAC professionals know how to access and evaluate a multitude of systems. They also know how to check for leaks and other potential problems.

If you’re having trouble with air quality, clogs in your ducts are often the culprit. Over time, dust and debris build-up, impeding airflow.

However, your HVAC ducts can also become infested with insects and pests. Even worse, mold and mildew can grow on the interior of the sheet-metal surfaces of your HVAC system.

Any of these circumstances can cause problems with your air quality. An HVAC expert can get to the root of the problem and fix it.

The Benefits of Clean Air Ducts

It’s important to have your air ducts cleaned regularly. Cleaning your ducts will improve the air quality of your home.

Every contaminant in your home gets sucked into your HVAC system. Even worse, it recirculates through your home several times a day.

Regular duct cleaning can remove these contaminants from your air. It will also help to mitigate various health issues. As a bonus, clean ducts will also help you to save on energy costs.

In most homes, 40% of the energy for heating and cooling gets wasted. This waste is mostly due to dirty or damaged air ducts.

Dirt in your HVAC system forces the system to work harder. By cleaning the ducts of your HVAC system, you can lower your energy bill.

You’ll also save money in the long run. Clean ducts will make your HVAC system last longer.

Also, a new HVAC system costs thousands of dollars. By maintaining your HVAC system properly, you can extend its life by years.

Investing in Indoor Air Quality

Black Family Laying On Ground In Home

You might also consider additional installations that will help improve the purity of your air. For instance, you may want to think about installing an air purification system. This kind of system is ideal for homes with limited ventilation.

Some systems use mechanical air filters, while others use an electronic system to clean the air. An air purification system uses ionization to remove airborne contaminants from the air in your home.

Here, we’ll take a brief look at different types of air purification systems.

Air Filters

If you’re going to go with an air filter system, you’ll want a four-stage filtration system. This kind of system attracts and traps airborne particles, helping to remove indoor air pollutants.

These pollutants might include:

• Bacteria
• Dust
• Dust mites
• Gases
• Mold spores
• Odors
• Pet dander
• Pollen
• Smoke
• Viruses
• VOCs

A good four-stage air filter system can capture up to 99.97% of air pollutants in your home as small as 0.30 microns.

Air Scrubbers

An air scrubber purifies your air. It reduces the number of particles that can aggravate allergies and asthma.

An air scrubber can protect the people in your home from dangerous pollutants. However, it also protects your HVAC system from dust build-up. In some cases, you can add an air scrubber to your existing HVAC system.

Air scrubbers do a great job of helping to improve air quality in your home. They’re even powerful enough for some commercial applications.

Ultraviolet Light 

NASA scientists developed ultraviolet light air cleaning technology. Originally, they made it for use in the International Space Station. Now, the technology is available in your home.

Ultraviolet light is a great system for the active purification of all your living spaces 24 hours a day. This kind of system might pair with an ionic air scrubber that destroys indoor contaminants.

An ultraviolet air scrubber is unique in that it cleans air even if it doesn’t pass to your HVAC system. Technicians can usually install it in any existing HVAC system.

These value-added air purification technologies can do a remarkable job of cleaning the air in your home. However, any air purification system is only as good as the technician who installs it. With this in mind, you’ll need an HVAC professional who can do the job right.

Start on the Path to Clean Air Today! 

We hope our complete indoor air quality guide has given you plenty of information to help you improve living conditions in your home. You deserve an HVAC system that will provide you with safety and comfort year after year. If you want to make sure the air in your home is safe, we can help.

One Hour Heating & Air Conditioning is your local expert in heating, air conditioning, and indoor air quality services. We proudly deliver fast service and exceptional customer care.

We work hard every day to earn our reputation as the best HVAC service around. Our technicians are trained to handle all brands of equipment and provide thorough inspections, tune-ups, repairs, and replacements. Best of all, One Hour Heating & Air Conditioning provides reliable service at fair prices backed by our 100% satisfaction guarantee.

Contact One Hour Heating & Air Conditioning today at (800) 893-3523 or connect with us online to request an appointment.