Do HEPA Filters Remove VOCs?

“HEPA filters excel at trapping particles like dust and allergens, but they are not effective in removing volatile organic compounds (VOCs) due to their gaseous nature. For comprehensive indoor air quality improvement, consider a multi-pronged strategy involving HEPA filtration, low-VOC product choices, specialized air purifiers, enhanced ventilation, and advanced technologies like activated carbon or photocatalytic oxidation to address both particles and VOCs.”

As an air quality specialist, I’m often asked if using a HEPA filter can effectively remove volatile organic compounds (VOCs) from indoor air.

VOCs are emitted as gases from some solids or liquids, such as furniture, paints, cleaning supplies, etc.

Exposure to high concentrations of VOCs can cause health issues like headaches, dizziness, and damage to the liver, kidneys and central nervous system.

Some common VOCs found indoors are:

• Formaldehyde
• Benzene
• Ethylene glycol
• Toluene
• Xylenes

So do HEPA filters help remove these harmful VOCs from the air you breathe every day? Let’s take a closer look at how HEPA filters work and their limitations when it comes to VOC removal.

What is a HEPA Filter?

HEPA stands for High Efficiency Particulate Air. As the name indicates, HEPA filters are designed to remove tiny particulate matter from the air.

Particles that can be captured by a HEPA filter include:

• Dust
• Pollen
• Mold spores
• Pet dander
• Smoke
• Bacteria
• Viruses

To qualify as a HEPA filter, it must satisfy these criteria:

• Remove at least 99.97% of particles that are 0.3 microns in size
• Have a tightly constructed filter material using random interlaced glass or plastic fibers

This construction allows very small particles to be trapped as air passes through the filter. Particles smaller than 0.3 microns are even more easily captured at higher rates.

HEPA Filter Effectiveness for Particles

Here’s how efficient HEPA filters are for removing various particle sizes from the air:

Particle Size	Removal Efficiency
0.3 microns	99.97%
0.1 microns	99.999%
0.05 microns	99.9999%

As you can see, HEPA filters are extremely effective at trapping microscopic particulate matter, including bacteria, viruses, smoke, and allergens. This makes them very useful for improving indoor air quality and health.

Do HEPA Filters Remove VOCs?

Now that we understand how HEPA technology works to filter out particles, let’s get back to our original question – can they remove gaseous VOCs?

Unfortunately, HEPA filters do NOT remove VOCs or other gases from the air.

The reason is simple – VOCs are not particles, they are chemical gases. The pores in the HEPA filter fiber mesh are too large to trap the smaller VOC molecules. So the VOCs simply pass through the filter unchanged.

While excellent for filtering particulate matter, HEPA filters have these limitations when it comes to VOCs:

• Do not capture or adsorb gaseous chemicals
• Allow VOCs to pass freely through filter material
• Do not breakdown or alter VOCs through chemical reactions

So using a HEPA filter alone is not effective for reducing VOCs and their associated health risks. It only addresses one part of indoor air quality issues.

Alternative Ways to Reduce VOCs

Since HEPA filters fall short for VOC removal, what other options should you consider for reducing VOC exposure?

Source Control

Limiting the amount of VOCs entering the indoor environment in the first place is ideal. Some tips:

• Choose low-VOC or zero-VOC paints, finishes, and adhesives
• Use green cleaning products without harsh chemicals
• Ensure proper ventilation when painting, refinishing floors, etc.
• Avoid purchasing furniture and goods with high VOC emissions

Local Exhaust

Use bath and kitchen fans to vent emissions directly outdoors before spreading through the home.

Air Purifiers

Specialized air purifiers with activated carbon filters can adsorb VOCs very effectively. The porous carbon has a huge surface area for trapping gaseous molecules.

Other technologies like photocatalytic oxidation (PCO) purifiers can actually break down VOCs into less harmful compounds.

Improved Ventilation

Increasing the amount of fresh outdoor air circulating indoors helps dilute VOCs and remove them from the home.

Make sure your HVAC system is running properly and bring in outdoor air as much as possible. Open windows regularly too.

The Bottom Line

While extremely useful for filtering airborne particles like dust, dander, and allergens, HEPA filters do NOT remove VOCs which are gaseous chemicals.

To reduce both particulate matter AND VOCs for better indoor air quality, utilize a multi-pronged approach:

• Use HEPA filters to remove particles
• Control VOC sources by choosing low-VOC products
• Improve ventilation and air circulation
• Use air purifiers with activated carbon or PCO technology to remove VOCs

Taking these steps together will minimize both particles and VOCs, creating the cleanest, healthiest indoor air possible. As an air quality specialist, I always recommend a complete strategy including HEPA filters plus VOC removal methods for optimal air quality and health.