Air quality monitors pros and cons

This article discusses the benefits of air quality monitors for measuring the quality of your indoor air. Additionally, a few disadvantages that you should be aware of are mentioned.

You can jump to the specific pros and cons by clicking on them in the list below.



The pros of air quality monitors


These pollutants can be detected by air quality monitors

Air quality monitors can measure a wide range of air pollutants. However, not every device measures the same compounds. The most commonly measured compounds are:

  • Particulate matter (PM2.5 – PM1)
  • volatile organic compounds (VOCs)
  • carbon dioxide (CO2)
  • radon gas

Particulate matter and volatile organic compounds are the most common indoor air pollutants. They pose a risk for our health and should be monitored constantly.

Carbon dioxide (CO2) is a naturally-occurring constituent of the air and is breathed out by humans and other animals. It becomes an issue only when CO2 gets excessively high. This mostly happens in poorly ventilated spaces where many people are present for a few hours.

Radon gas is a natural gas that is only present in certain areas of the world. It is, however, very dangerous to our health since it can cause lung cancer. For more information about radon, please read my article: What is radon?

I wrote an in-depth article on all the compounds that can be measured by air quality monitors. You can find it here:


Detecting chemicals that can’t be detected by sight or smell

The human nose is adept at detecting ceratin airborne compounds that have odors. In this way, we can naturally detect for example some VOCs (with a pungent smell), or natural gas (although the smell is added). However, many air pollutants do not have a scent, nor do they have a color, taste, or cause a directly noticeable reaction in our body.

Air quality monitors are able to detect particles and gasses that we otherwise would never be able to detect. For example, radon, which is an odorless, colorless, tasteless gas is very dangerous. According to the US Environmental Protection Agency, radon gas is the number one cause of lung cancer among non-smokers in the United States. And people who do smoke increase their chance of lung cancer by 25 times when regularly being exposed to radon.

Without air quality monitors we would never be able to detect these compounds. Knowing which compounds are present and when to take action is a huge step toward creating a healthier indoor environment.


An air quality monitor shows exactly how healthy your air is

During my environmental sciences studies, I learned that for many toxins and pollutants the dose determines the danger. This means that not necessarily the compound, but mostly the amount you are exposed to determines whether it’s dangerous. An air quality monitor shows you exactly how much of a certain compound is present. Therefore, you know precisely when to act and when not to worry.

This is especially true for, for example, CO2. CO2 naturally occurs in nature, is crucial for the growth of plants, and is breathed out by humans and other animals. However, when CO2 levels become too high, it can have detrimental effects. For example, climate change is a commonly known problem caused by an increase of CO2 in the atmosphere. The levels of atmospheric CO2 (approximately 400 ppm) do luckily not have an impact on our health directly.

However, extremely high CO2 levels (above 1000 ppm) can build up in poorly ventilated indoor areas. with these concentrations of CO2, negative health effects like drowsiness can occur. You can find more information on the effects of CO2 on our health in my article: What are healthy indoor CO2 levels? (safe levels, health effects, and what to do about them)

Knowing exactly what levels of a certain compound are in your air allows you to take appropriate measures. Most air quality monitors indicate if a measured compound is in a safe range or is exceeding recommended levels and action needs to be taken.


Temperature, humidity and pressure are measured

In addition to harmful airborne substances, most air quality monitors also measure the temperature, humidity, and air pressure. These factors, although not directly harmful to our health, do influence the healthiness of the air we breathe. Additionally, they greatly contribute to our feeling of comfort.

Too humid air (above 60% relative humidity) results in less thermal comfort. High humidity causes us to experience both heat and cold more intensely. Therefore, knowing your air’s humidity levels and taking action (such as using a dehumidifier) can improve our comfort. You can read all about dehumidifiers in my article: Dehumidifiers pros and cons.


Air quality monitors can help detect mold growth

An air quality monitor cannot directly measure mold spores in the air or find spots where mold is growing. Mold spores are always present in normal background amounts. However, because air quality monitors measure both temperature and humidity, they can help predict and detect mold growth.

Mold requires a relative humidity of $70 or higher or spots with regular condensation. Therefore, humidity levels are a good indication of the possibility of mold growth. Some air quality monitors, however, have an additional function that predicts mold growth based on the data it has gathered in your house.

For more information on how to detect mold using an air quality monitor, I recommend reading my article: Can air quality monitors detect mold? (this one can).


Taking action based on knowledge and data

An air quality monitor gives excellent in-depth data on the quality of the air. Data on many different compounds such as particulate matter and CO2, as well as conditions such as temperature and humidity, are shown in detail and are available in graphs. Additionally, an air quality monitor knows what healthy air looks like, and notifies you when there is an issue. In this way, you get an excellent overview of your air quality over time.

Additionally, the Airthings Wave Plus, for example, connects to an app that shows graphs of your air quality over time and gives you notifications as well as tips and insights. Because your air quality monitor gathers data over time, you will start to learn exactly when you need to take action to prevent one or more pollutants from building up.

So, in short, you can:

  • keep track of your air quality in real time on the device
  • see detailed information per pollutant
  • get noditfied when one or more pollutants exceed standards
  • see air quality data over time on an app on your phone
  • get tips and insights about your air

With an air quality monitor, you won’t be in the dark anymore about the air you breathe


An air quality monitor helps create a healthy and comfortable home (+ examples)

Although an air quality monitor does not clean the air, knowing exactly how your air is doing empowers you to take action. With the data and knowledge provided by an air quality monitor, you will be able to create the healthiest and most comfortable home environment possible. You can:

  • detect specific air quality issues such as:
    • pollutants like PM or VOCs
    • suboptimal conditions like temperature and humidity
  • know exactly when and for how long you need to increase ventilation
  • tackle the root cause of indoor air pollutants

An air quality monitor gives you a wealth of knowledge. You can use this to make sure your indoor air is always in optimal condition. Here I give some examples of situations that may occur:

You normally start to feel a little sleepy after a few hours of working from home. With your new air quality monitor, you discover that CO2 levels start to rise the moment you start your work, and the levels exceed 1000 ppm around the time you normally felt like getting a coffee to wake you up again. You learn that opening a window during your short break makes the CO2 levels drop again to normal levels. You can now simply drink a glass of water and work more effectively because of the clean air.

In the morning, your indoor air often smells musty, is not comfortable and you experience respiratory complaints. With your new air quality monitor, you discover that you have relatively humid air, often exceeding 70% relative humidity during the night. Your smart air quality monitor indicates that you might have mold growth. Because of this, you discover some spots that have started mold growth and clean them out. To prevent this from happening again, you decide to purchase a dehumidifier to lower the humidity. Your house immediately becomes much more comfortable and the musty smell is gone.


Why I prefer an air quality monitor over an air purifier

It might seem that we’d be better off using an air purifier to actually clean the air rather than only measuring what’s wrong with a monitor. However, I will argue why I prefer an air quality monitor over a purifier.

Although an air purifier can clean the air of particles and gasses, this can often be done as well by ventilating properly. In general, according to the US Environmental Protection Agency, indoor air is 2 to 5 times more polluted than outdoor air. Therefore, having sufficient ventilation will solve most of our indoor air problems.

An air purifier has the disadvantage that it does not tell you how your air is doing (with the exception of some advanced purifiers). You might have a serious air quality issue that simply can’t be handled by the purifier, and you will not know about it. Except for, in some cases, the negative health effects associated with it.

On top of that, some compounds can not or barely be removed by an air purifier. CO2 is an example of a hard-to-control compound. If you want to read more about CO2, I recommend reading my articles: What are healthy CO2 levels? (safe levels, health effects, and what to do about them) as well as: Do air purifiers reduce CO2?

Also, how do you know you need an air purifier, and for what problem exactly? The only way of knowing for certain that a purifier will solve any issues is to measure what issue you have. It might very well be that an air purifier is the solution to your air-related problems, but it also might not be.

In general, an air quality monitor gives you great insights into your air quality and helps determine what actions you need to take.

Because of this, I prefer a good air quality monitor over an air purifier. I recommend taking a look at the Airthings air quality monitors. If you purchase one via this link to the Airthings Wave Plus air quality monitor and use the coupon code 665381-10OFF, you will get a 10% discount.



Commercial air quality monitors are very accurate and easy to operate

You do not need a massively expensive scientific-grade air quality monitor to get an accurate reading of your air. You also don’t need to hire an expert to measure it for you. Presently available cheap air quality monitors have been tested to give very accurate data on your air (<5% off from the actual value), and the data can easily be seen and interpreted on an app on your phone.

A study performed by the Mackintosh Environmental Architecture Research Unit in 2018 compared expensive scientific-grade monitors to affordable (<$200) commercial air quality monitors. This study concluded that “The findings suggest that low-cost monitors, such as the Foobot FBT0002100, have the potential to identify high pollutant exposures and to provide high-density, reliable, temporal data…” (source)

For more detailed information on air quality monitor accuracy, you can read my article: How accurate are commercial air quality monitors?



The cons of air quality monitors


An air quality monitor does not clean the air

Air quality monitors are purely there to measure what is in your air and to let you know if you have any issues. They do not filter or clean the air, and the air remains as dirty as was measured if you do not take any action.

To clean the air, you can either improve ventilation, air out the house more often, or change certain habits that tend to pollute the air. Another option is to purchase an air purifier. This only works if you have one or more pollutants that can be cleaned by an air purifier. In this article, I mentioned why I prefer an air quality monitor over an air purifier.


Air quality monitors do not show the source of pollutants

A disadvantage of air quality monitors is that they can’t tell you where the pollutants are coming from. Therefore, the data provided by your monitor can mostly be used to inform your habits. You can, for example, increase ventilation or purchase a device that helps clean the air such as a purifier or (de)humidifier.

However, the data provided by your air quality monitor can give you an indication of what the problem might be. For example, if your particulate matter content is too high between 7:00 and 11:00 and between 17:00 and 21:00. If this is the case, it is likely that air pollutants from nearby traffic are getting into your house, since these are the hours at which traffic is at its peak.

This might inform you to reduce ventilation during these hours, and use an air purifier. You might also change your workout schedule based on this information.

The average commercial air quality monitor costs $150

An air quality monitor that measures at least particulate matter (PM), carbon dioxide (CO2), and VOCs can cost between approximately $50 and $300. Depending on your budget and needs, this can be a steep cost.


How to decide which air quality monitor to buy

If you are considering purchasing an air quality monitor, you can expect to pay about $100-300 excluding shipping costs. The price highly depends on its features and the compounds it can measure. I highly recommend choosing a monitor that at least measures particulate matter (PM), carbon dioxide (CO2), and VOCs.

Radon gas is less important unless you live in an area where radon is prevalent. You can read more about radon and find out if it is an issue in your area in my article: What is radon? (origin, health risk and preventive measures).

Carbon monoxide (CO) is often not measured by air quality monitors, although it is very important to measure. However, it should be measured by a separate CO monitor anyway, even if your air quality monitor can measure it.

Temperature, humidity, and air pressure are even less important since they are not directly harmful to your health. However, temperature and humidity do influence our thermal comfort. Therefore, if you want to create the most comfortable and healthy indoor environment and do not already measure these, I recommend selecting a monitor that does measure them.

It can be hard to choose which air quality monitor to buy. There are numerous features that you need to consider such as:

  • what compounds it can measure
  • if you need the advanced features such as an app and pollen level indicator
  • its battery life

I recommend checking out my article: These compounds can be measured by air quality monitors – a complete list plus examples. This article includes several good-quality air quality monitors and includes tables that show what they can measure, what extra features they have, as well as their price and battery life.

The air quality monitor that can measure the most compounds and is actually fairly cheap at $76 is the Biaoling. It does, however, not measure temperature, humidity, or air pressure. You can find the Biaoling here on amazon.com.


Most air quality monitors do not measure carbon monoxide

Almost none of the available air quality monitors can measure carbon monoxide (CO). Although technically a lacking feature, I would honestly prefer my air quality monitor not to measure CO. This is the case since CO should be measured constantly by a separate CO monitor. CO is very dangerous and cannot be detected by smell, color, or taste.

If you do not already measure CO with a special CO monitor, I recommend purchasing a separate CO monitor that can run 24/7. It is not a good idea to rely on your air quality monitor for CO measuring since they often don’t have the battery life to run continuously. Also, CO should be measured at a specific height (about 5 feet off the ground).

You can find cheap CO monitors here on amazon.com.



Measured VOCs include both harmful and harmless compounds

Volatile organic compounds are a large group of compounds that are being lumped into one reading. This means that the VOC readings include both harmless chemicals such as odors as well as harmful ones such as formaldehyde.

Because of this, it is hard to identify if a high VOC reading is a problem. What you can do each time VOC readings are high is check whether there is an obvious source. For example, if you are measuring during dinner, you might get high readings of VOC. However, these VOCs are likely to be the odors of your meal and completely harmless.

However, when you get high reading when you are painting your walls, you should increase your ventilation since these VOCs can be harmful.

If you are concerned about this aspect of air quality monitors, I recommend looking for a monitor that can measure formaldehyde separately. Formaldehyde is a common harmful VOC. An excellent air quality monitor that can measure formaldehyde is the popular Temptop m10 (amazon.com)


Air quality monitors require up to 7 days to calibrate

Air quality monitors can take up to 7 days to calibrate. During this time period, they will still show their measurements. However, they will not be perfectly accurate until the calibration time has passed. For measurements of temperature, humidity, and air pressure, no calibration period is required.

Air quality monitors from Airthings, for example, will have a deviation of 10% on their measurements in the first week of sue. This means that the readings will be about 10% higher or lower than the actual condition of the air. After a month, their accuracy has increased to a maximum of 5% deviation.

The calibration period is needed for the device to learn from its own measurements and make sure to give the most accurate readings. For example, some conditions of the air such as temperature and humidity can influence the readings on for example the number of particles in the air. Therefore, the device needs to adjust for these factors. This takes time.

Some air quality monitors, like those from Airthings, give a clear indication of how much time is left until it is fully calibrated. The company Airthings even states on their website that, specifically for radon measurements, they advise measuring for at least 30 days before taking action on their device’s readings.

Additionally, air quality monitors require some time to give accurate readings. Therefore, they do not give an accurate reading the instant you turn them on. In general, the longer you measure, the more accurate the readings become. Stationary measurements of at least 60 minutes are recommended for the most accurate readings.


Conslusion: air quality monitors are worth it

I think air quality monitors are an excellent tool to improve our well-being and health. In my article: Are air quality monitors worth it? I discuss why I think air quality monitors are worth it based on their benefits, shortcomings, and costs.

Get a 10% discount on Airthings air quality monitors

I managed to arrange a discount for people reading my website! By using this link to the Airthings discount store you will get a 10% discount when entering this coupon code at checkout: 665381-10OFF.

In my opinion, the best overall air quality monitor is the Airthings View Plus, you can purchase it here with 10% discount when using the coupon code above.