Can HVAC Filtration Help Reduce Airborne Microplastics?

Microplastics are becoming part of the indoor air quality conversation. While many people think of microplastics as something found in water or food, research is also looking at how small plastic particles and fibers may move through the air inside homes, offices, schools, and other buildings. Indoor environments are increasingly recognized as an important pathway for airborne microplastic exposure, although methods and findings are still developing.


For IAQ professionals, one practical question is worth asking: Can HVAC filtration help reduce airborne microplastics?

The answer is yes, filtration may help reduce airborne particles, including some microplastics. But it is important to understand what filtration can do, what it cannot do, and why proper maintenance matters.


What Are Airborne Microplastics?

Microplastics are very small plastic particles, generally smaller than 5 millimeters. Indoors, they may come from synthetic textiles, carpets, upholstery, furniture, packaging, electronics, plastic-based materials, and settled dust.

Some microplastics can become airborne through normal building activity. Walking, cleaning, opening and closing doors, using HVAC systems, or disturbing soft materials can move particles from surfaces into the air.

Because indoor spaces are enclosed, these particles may settle, recirculate, or build up in dust if they are not managed through source control, cleaning, ventilation, and filtration.

How HVAC Filtration Fits Into the IAQ Picture

HVAC filters are designed to capture particles from air moving through the system. Depending on the filter rating, system design, air flow, installation, and maintenance, filtration can help reduce the amount of particulate matter circulating indoors.

This matters because airborne microplastics are part of the broader particle conversation. They may vary in size, shape, and material. Some may be large enough to settle quickly, while smaller particles and fibers may remain suspended longer and move through indoor air.

A good HVAC filtration strategy may help capture some of these particles, especially when filtration is properly matched to the building and system.


Understanding MERV Ratings

Many HVAC filters are rated using MERV, which stands for Minimum Efficiency Reporting Value. MERV ratings help describe how well a filter captures particles within certain size ranges. ASHRAE Standard 52.2 is the commonly referenced method for evaluating filter performance by particle size range.

In general, higher MERV ratings capture smaller particles more effectively. ASHRAE has recommended MERV 13 filters where systems can accommodate them, and notes that many relevant indoor particles fall within the 1 to 5 micron size range.

However, a higher MERV filter is not always automatically better for every system. If the filter creates too much resistance, it may reduce airflow or place stress on equipment. IAQ professionals should consider system compatibility before recommending or installing a higher-efficiency filter.



What About HEPA Filtration?

HEPA filtration is another important part of the conversation. According to the U.S. Environmental Protection Agency, HEPA filters can theoretically remove at least 99.97% of airborne particles at 0.3 microns, including dust, pollen, mold, bacteria, and other particles.

Most standard residential or commercial HVAC systems are not designed to use true HEPA filters without special equipment or system modifications. However, portable air cleaners with HEPA filtration may be useful in certain rooms or areas when they are properly sized, placed, and maintained.

For microplastics, this means HEPA filtration may help reduce airborne particles in the size ranges the filter is designed to capture. But it should not be presented as a complete solution or a replacement for good building practices.


Maintenance Matters

Even a good filter cannot perform well if it is not maintained.

A practical filtration plan should include:

  • Using a filter that fits properly in the system
  • Replacing filters on the recommended schedule
  • Checking for gaps, bypass, or poor filter seating
  • Making sure the HVAC system can handle the selected filter
  • Keeping return vents and supply vents clear
  • Evaluating whether additional portable filtration is needed in high-use spaces

Filter bypass is especially important. If air can move around the filter instead of through it, particle capture is reduced. Proper installation and routine inspection are simple but important steps.


Realistic Expectations

HVAC filtration can support better indoor air quality, but it is only one part of a larger strategy.

Filtration may help reduce airborne particles, including some airborne microplastics. But it will not remove particles already settled in dust, eliminate the source of shedding materials, or address all indoor contaminants.

A stronger IAQ approach includes:

  • Source control
  • Regular dust management
  • Proper ventilation
  • Appropriate HVAC filtration
  • Portable air cleaning where needed
  • Moisture and humidity control
  • Routine inspection and maintenance

This balanced approach is especially important when discussing emerging topics like microplastics. The goal is not to create alarm. The goal is to help building owners, facility managers, and occupants understand practical ways to reduce exposure while the science continues to develop.


What IAQ Professionals Can Tell Clients

When clients ask about microplastics and filtration, a simple explanation may help:

“HVAC filtration can help reduce some airborne particles, including particles that may include microplastics, but it works best as part of a broader IAQ plan. The right filter, proper system compatibility, regular replacement, good cleaning practices, and source control all matter.”


The Bottom Line

HVAC filtration can help reduce airborne particles indoors, and it may play a role in reducing some airborne microplastics. But filtration should be presented with realistic expectations.


For IAQA members and IAQ professionals, microplastics are another reminder that indoor air quality is connected to building materials, occupant behavior, cleaning practices, ventilation, filtration, and ongoing maintenance.

Air Purifiers vs. Proper Ventilation: What Does Your Building Really Need?

By Donna Lawrence • June 17, 2026
If you've ever walked into a stuffy room and wondered, "Should I just buy an air purifier?" You're not alone. Air purifiers are popular, easy to buy, and heavily marketed. But here's the truth: an air purifier and proper ventilation are not the same thing, and one cannot replace the other. Let's break it down in simple terms. What Does an Air Purifier Do? Think of an air purifier like a vacuum cleaner, but for the air. It pulls in the air inside your room, filters out dust, pollen, smoke particles, and other tiny pollutants, and then pushes cleaner air back out. Air purifiers are great at: Capturing fine particles like dust and allergens Reducing smoke and wildfire-related pollution indoors Filtering pet dander and mold spores But here's the catch: an air purifier only cleans the air that's already inside your building. It doesn't bring in any fresh air from outside. What Is Proper Ventilation? Ventilation is the process of swapping out stale indoor air with fresh outdoor air. It's like opening a window, except in most buildings, it's done through carefully designed systems like HVAC units, exhaust fans, and air ducts. Good ventilation: Brings in fresh air and removes stale, CO₂-heavy air Dilutes indoor pollutants that build up over time Controls humidity, which helps prevent mold growth Keeps air moving throughout the whole building Without proper ventilation, pollutants from cleaning products, furniture, cooking, and even the people inside the building accumulate, and no air purifier can fully solve that problem. So What's the Difference, Really? Here's a simple way to think about it:

IAQA: Dedicated to Your Education and Success

November 17, 2025
When you think about vendors, you probably picture suppliers, service providers, or consultants—businesses that support your operations and help you succeed. But have you ever considered that IAQA, your professional association, is one of the most valuable vendors you have? Membership in IAQA isn’t just about being part of a group; i t’s about leveraging resources, education, and networking to strengthen your business. IAQA provides the tools, connections, and industry credibility that help you grow professionally and stay ahead in a competitive market. Here’s why IAQA is an indispensable vendor and how we deliver value that goes far beyond a typical business transaction. Connecting You with Clients: Find A Pro Listings Visibility is key in any industry, and IAQA helps put your name in front of potential clients. Through Find A Pro , members gain exclusive access to a platform designed to connect them with people actively seeking their services. Unlike traditional marketing expenses, this is a built-in benefit of membership—giving you exposure without additional advertising costs. Ongoing Professional Development and Education Staying competitive means staying informed. IAQA provides year-round learning opportunities , including: The Annual Conference and regional events , where members can gain insights from industry leaders and sharpen their expertise Webinars on industry trends, business strategies, and technical skills IAQA University (new content currently in development!) , offering in-depth training IAQA serves as a trusted vendor for professional growth—ensuring you’re always learning, improving, and staying ahead of industry changes. Boosting Your Credibility and Industry Authority Being part of a respected association automatically enhances your credibility. IAQA promotes its members as recognized experts in their field, positioning them as go-to professionals for IAQ-related services and events. The IAQA brand strengthens your reputation , reinforcing that you are a dedicated and knowledgeable professional in your field. Networking: Access to Seasoned Professionals Who Share the Same Challenges The IAQA member’s only Community Page acts as a hub for knowledge-sharing , giving you access to experienced professionals and peers who face the same challenges that you do. Become an active participant on our Community Page and learn from others’ experiences and challenges on this informal member’s only platform. Help When You Need It: Dedicated Member Support IAQA is committed to supporting you every step of the way. Whether you need assistance navigating industry challenges, finding resources, or simply getting a question answered, your professional, dedicated staff is here to help. Having a reliable resource like this can be the difference between struggling through an issue alone and finding a quick, effective solution with the help of an industry expert. Exclusive Discounts: Savings That Add Up Running a business comes with expenses, but being part of IAQA can significantly cut some of those costs. Members receive: Discounted rates for conferences, regional events, and other continuing education Savings on supplies, equipment, and lab services from industry partners and vendors Special members-only pricing on professional development tools These discounts quickly offset the cost of membership, making IAQA a valuable financial partner as well as a professional one. A Commitment to Your Success At the heart of it all, IAQA is more than a vendor, we are a partner in your success . Every benefit, resource, and service is designed with one goal in mind: helping you thrive .

Build a Smarter, Stronger Organization Through Ongoing Education

November 17, 2025
Inspire and empower your team with the gift of knowledge! 2026 Webinar Series: Equip your team with the latest industry insights and skills. Florida Forum 2026 in Bonita Springs, FL February 17 & 18 2026 Annual Conference in Carlsbad , CA. Dive in to learning while fostering connection and collaboration in an inspiring and fun environment. Conference Videos: 2024 and 2025 are available for purchase. If you couldn't make it to the conference, or want to share what you learned with your team, videos are a great way to set up staff Lunch & Learns. Coupon codes are available for members and conference attendees. Continuing education is the perfect way to show your team you value their growth and professional development.