The Jury Is Out: Plants Can Improve Indoor Air, But an HVAC Filter Helps Too  

New Research Suggests Air Purification Might Work More Effectively 

Air Filters, Indoor Air Quality

Back in 2018, the evidence was seemingly clear. Using data from an experimental NASA study, indoor plants were shown not only to absorb carbon dioxide, but remove common household VOCs in small, airtight containers. Coupled with incontrovertible research that shows people feel better in greener environments, it seemed a slam dunk.

Houseplants were seen as a not-so-secret weapon against the common irritants and plain old dangerous gases like formaldehyde emitted by household cleaning products, new carpets, drapes and furniture, and even popular indoor-use wall paints. We discussed it in a blog here, along with suggestions for plants you could use to facilitate cleaner air and greater indoor comfort. 

Well, now a recent study has changed all that.

While we’re disappointed at the outcome (who doesn’t want lots of plants in their home? And it’s nice to think of them as somehow able to clean as well as look beautiful), the reality is that HVAC air purifiers and sanitizers are more effective at keeping you safe than the English Ivy you picked up at the supermarket.

Call us Captain Buzzkill, but we thought it’s important that you know. 

This new research was published in the feel-good Journal of Exposure Science and Environmental Epidemiology. In this paper, air quality expert and environmental engineer Michael Waring reviewed past studies on plants removing VOCs (volatile organic compounds) in the air around them.

Applying the data to more typical household or office environments (rather than airtight boxes), Waring was able to standardize the results of previous work to compare how well a plant could clean a room to the results generated by a mechanical air purifier, much like the ones Air-Tro installs for our customers. His conclusions were startling. As he describes to the National Geographic Magazine: 

“Plants, though they do remove VOCs, remove them at such a slow rate that they can’t compete with the air exchange mechanisms already happening in buildings.” 

To truly remove the amount indoor air pollution commensurate with what an HVAC air purification system can do, Waring reported that you would need a “veritable forest” inside your home or commercial building. 

So, if you’re worried about VOCs and off-gassing, while plants may not be the panacea we once thought they were, there are actions you can take right now to have a cleaner, healthier indoor environment.

Plentiful ventilation, a properly maintained HVAC system, and frequent air filter changes are a great place to start. Consider reducing your exposure to numerous harsh chemical cleaners and look for products with lower VOCs. Talk to your HVAC professional about practical air purification equipment you can add to your current heating and air conditioning system. With more options than ever before, we can help you find cost-effective solutions for maintaining clean and safe indoor comfort. 

And remember, NASA still keeps plants on the space station. Why? As we mentioned earlier, studies show that house plants improve your mood, reduce symptoms of stress or depression, and make you more productive. While they may not rid the air of all VOCs, they’re still worth having around. 



Is it time for an air purification system in your home? Talk to the experts at Air-Tro. We’re the indoor comfort specialists the San Gabriel Valley trusts, since 1969! Call us at (626)357-3535.