Health & Wellness #87: Indoor Air Quality: The Best Houseplants and Filters for a “Clean Air” Home

According to the U.S. Environmental Protection Agency (EPA), indoor concentrations of certain pollutants are frequently 2 to 5 times higher than outdoor levels. Because the average person spends over 80% of their time indoors, optimizing indoor air quality (IAQ) is one of the most effective steps you can take for long-term health and wellness.

Creating a “clean air” home requires a dual approach: active mechanical filtration to remove airborne particulate matter and phytoremediation (plant-based air cleaning) to boost humidity and absorb ambient volatile organic compounds (VOCs).

1. The Heavy Lifters: Mechanical Air Filters

While houseplants add aesthetic and biological value, mechanical air purifiers do the heavy lifting when it comes to removing microscopic dust, pollen, mold spores, and combustion particles (Meattle, 2009).

• True HEPA Filters: High-Efficiency Particulate Air (HEPA) filters are engineered to remove at least 99.97% of airborne particles as small as 0.3 microns. Stand-alone portable HEPA units significantly reduce indoor fine particulate matter concentrations and improve respiratory health outcomes (Chen et al., 2022).

• Activated Carbon Filters: Standard particle filters do not trap gases or odors. Activated carbon filters use porous charcoal to adsorb VOCs, formaldehyde, and smoke fumes.

• HVAC MERV Ratings: For whole-home systems, upgrade to a filter with a MERV 13 rating or higher to capture fine particles without restricting system airflow.

2. Botanical Boosters: Best Houseplants for Indoor Spaces

The concept of using plants to purify air originated with NASA’s seminal 1989 Clean Air Study (Wolverton et al., 1989), which demonstrated that root microflora and foliage absorb volatile toxins like benzene and formaldehyde in sealed test chambers. While plants in standard living rooms work at a slower exchange rate than mechanical purifiers, they excel at raising beneficial humidity and removing trace pollutants over time.

3. Actionable Tips for a “Clean Air” Home

1. Match CADR to Room Size: When buying an air purifier, ensure its Clean Air Delivery Rate (CADR) matches or exceeds your room’s square footage.

2. Combine Technologies: Place a True HEPA purifier with an activated carbon filter in high-activity areas, and distribute 1–2 houseplants per 100 square feet for holistic air balancing.

3. Control the Source: Minimize indoor synthetic fragrances, gas stove emissions without ventilation, and harsh chemical cleaners.

4. Maintain Filter Schedules: Replace HEPA filters every 6–12 months and pre-filters every 3 months to maintain optimal airflow.

Recommended Video Resource

To learn more about optimizing indoor air through natural systems and smart engineering, watch the popular TED Talk on indoor environmental wellness:

• Video Title: How to Grow Fresh Air by Kamal Meattle (TEDTalks)

• What You’ll Learn: A practical real-world case study on how combining specific houseplants (Snake Plant, Areca Palm, Money Plant) with proper air management dramatically improves building air quality.

References

Chen, C.-F., Hsu, C.-H., Chang, Y.-J., Lee, C.-H., & Lee, D. L. (2022). Efficacy of HEPA Air Cleaner on Improving Indoor Particulate Matter 2.5 Concentration. International Journal of Environmental Research and Public Health, 19(18), 11517. https://doi.org/10.3390/ijerph191811517

U.S. Environmental Protection Agency. (1989). Report to Congress on Indoor Air Quality: Volume II: Assessment and Control of Indoor Air Pollution (EPA/400/1-89/001C). Office of Air and Radiation.

U.S. Environmental Protection Agency. (2023). Indoor Air Quality: Report on the Environment. U.S. EPA. https://www.epa.gov/report-environment/indoor-air-quality

Wolverton, B. C., Douglas, W. L., & Bounds, K. (1989). A study of interior landscape plants for indoor air pollution abatement (NASA Technical Report TM-108061). NASA National Space Technology Laboratories.