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Improve Air Quality Naturally – Simple Solutions For the Indoor Environment

improve air quality naturally, ventilation, open window

In a world filled with several options for expensive, “cutting edge” air purifiers and filters, there are several simple steps that can be taken to improve air quality naturally. This post will highlight what to do, or what not to do, to improve the indoor air quality (IAQ) naturally.


The simplest way to improve IAQ is by increasing the ventilation in the space. This means introducing outdoor air into the building. Homes tend to be very closed up to the outside, which is good to maintain thermal comfort indoors but bad for the IAQ. Introducing outdoor air dilutes the contaminants that are present inside. Opening a window is a very simple way to get more airflow and improve the general indoor air quality naturally in a space.

Source Control

Preventing contaminants from causing problems in the first place is probably the best way to improve the indoor air quality naturally. This is known as source control and it can begin at the early stages of building a home. Choosing finishes such as cabinets, flooring, and paints that emit low or no volatile organic compounds (VOCs) can prevent off-gassing and lower VOC levels in the home. It is best to select durable materials that don’t require harsh chemicals for cleaning and maintenance 1. Another simple way to implement source control is by purchasing fragrance-free or no-VOC personal care products and household cleaners.

Can Plants Improve Air Quality Naturally?

Implementing source control to prevent IAQ problems can even be used when considering the use of potted plants in a space. Yes, plants! I enjoy having plants in my home and very much enjoyed my botany class in college, but unfortunately, they are not the miracle solution to improve air quality naturally.

A famous study conducted by NASA in 1989 showed that when a pollutant was injected into a sealed chamber, a plant could reduce the VOC levels by as much as 90% in a 24 hour period2. This study had many problems. This experiment does not show the impact that ventilation would have in a real-world situation. A separate study conducted by the Associated Landscape Contractors of America & Healthy Buildings International conducted a field experiment in an office building which compared the levels of certain contaminants on different floors with and without plants3. The result showed “no reduction of pollutant concentrations”4. The NASA experiment also fails to provide the mass of pollutant removed per hour per plant which would be useful information in order for it to have real-world applications. To learn more about plants and indoor air quality, we recommend reading “How Well Do House Plants Perform as Indoor Air Cleaners?

Many people use plants to increase the oxygen levels, however, the increase is usually so small that it is difficult to even measure.

Not only do plants fail to remove significant levels of indoor air pollutants, they also can add some pollutants. Over-watering plants can lead to mold and bacteria problems. Some plants may require pesticides and fertilizers that can have a negative impact on IAQ.

Essential Oils

Now to burst another bubble. Essential oils are often seen as natural and beneficial to human health. They are used for aromatherapy, in yoga studios, and as a deodorizer. As it turns out, essential oils may do more harm than good. Essential oils are made through the distillation of natural materials such as citrus rinds. (I have even distilled my share of essential oils in a chemistry class in the past.) The distillation process produces terpenes. These terpenes can interact with free radicals in the air such as hydroxyls and ozone and yield formaldehyde and organic aerosols which are fine and ultrafine particles5. One study of a spa studio found that the total VOCs and fine particle pollution increased when essential oils were used6.  Clearly, essentials oils do not improve air quality naturally.


If you are interested in improving your indoor air quality naturally, the best strategy is source control and outdoor air ventilation. Be careful with using houseplants or essential oils to improve air quality. Plants and oils may create a peaceful indoor environment, but they will likely reduce the air’s quality.

If you are concerned about your indoor air quality contact our office.

  1. Development of a design guide to improve building IAQ, Andrew, P., et. al., 2008.
  2. Interior landscape plants for indoor air pollutant abatement, Final Report, Wolverton, B.C., et. al, 1989.
  3. Potted-plant/growth media interactions and capacities for removal of volatiles from indoor air, Proceedings of Health Buildings, Wood, R.A. et. al., 2003.
  4. Potted-plant/growth media interactions and capacities for removal of volatiles from indoor air, Proceedings of Health Buildings, Wood, R.A. et. al., 2003.
  5. Effects of essential oils on formation of formaldehyde and secondary organic aerosols in aromatherapy environment, Huey-Jen, et. al.
  6. Effects of essential oils on formation of formaldehyde and secondary organic aerosols in aromatherapy environment, Huey-Jen, et. al.

Ian Cull

Ian Cull is a nationally recognized expert in the field of indoor air quality. He is the Chief Science Officer of Indoor Science, a company he started in 2004. He speaks around the world on air quality topics and is a training provider of the Indoor Air Quality Association. Mr. Cull is a Licensed Professional Engineer (PE) and Certified Industrial Hygienist (CIH). His degree is in Environmental Engineering from the University of Illinois - Urbana Champaign. Mr. Cull has developed 50 air quality related courses for the IAQA University and is the author of the book, “Fundamentals of Mold Remediation”. In his words… “Besides being passionate about indoor air quality, I enjoy cycling, music, the Chicago Bulls, and having fun with my three kids.”