HEPA and MERV filters both remove particles from the air, but they are not the same type of filtration rating.

For a commercial building, the better choice depends on where the filter will be used and how much particle removal the building needs.

In simple terms:

That does not mean every commercial building should replace its HVAC filter with HEPA.

Most HVAC systems are designed to operate within a certain range of airflow resistance. Installing a filter that is too restrictive can reduce airflow if the system is not designed for it.

That is why many buildings use an approach such as:

What Does MERV Mean?

MERV stands for Minimum Efficiency Reporting Value.

It is a rating system developed through ASHRAE Standard 52.2 for general ventilation air filters.

The current ASHRAE Standard 52.2-2025 evaluates air-cleaning devices against particles ranging from 0.3 to 10 microns.

MERV ratings range from 1 to 16.

In general:

Higher MERV number = greater particle-capture efficiency

For example, EPA lists:

The HEPA figure is shown for comparison. HEPA itself is not a MERV rating.

What Is a HEPA Filter?

HEPA stands for high-efficiency particulate air.

EPA defines a HEPA filter as a pleated mechanical filter capable of theoretically removing at least 99.97% of airborne particles at 0.3 microns.

Particles both larger and smaller than 0.3 microns can also be captured effectively.

HEPA filtration is commonly used where a high level of airborne particle removal is wanted.

That may include:

• Portable commercial air purifiers
• Ceiling-mounted air purifiers
• Industrial air-cleaning systems
• Medical and laboratory applications
• Dedicated room air-cleaning equipment

For a deeper explanation of how the filter actually captures particles, see our guide to HEPA filtration systems.

Is HEPA the Same as MERV 17?

No.

This is a common misunderstanding.

The standard MERV scale runs from MERV 1 through MERV 16.

HEPA is evaluated under a different high-efficiency filtration standard.

ASHRAE also treats HEPA separately from MERV filtration and notes that HEPA filters are more efficient than MERV 16.

Is HEPA Better Than MERV?

If you are looking only at particle filtration efficiency, HEPA provides greater efficiency than standard MERV filters.

But that does not automatically make HEPA the better choice for every part of a commercial building.

The real question is:

Where is the filter being installed?

For example:

A MERV 13 filter may be appropriate inside a commercial HVAC system designed to handle it.

A dedicated HEPA air purifier may be used in the room to provide additional high-efficiency particle filtration.

Those two systems can work together instead of competing.

Why Not Put HEPA Filters in Every HVAC System?

Air has to move through the filter.

As filtration becomes more efficient, the filter design can create greater resistance to airflow.

ASHRAE notes that filter performance needs to be considered alongside airflow resistance.

An HVAC system has a fan designed to move a certain amount of air against a certain amount of resistance.

If a filter is more restrictive than the system was designed to handle, possible problems can include:

• Reduced airflow
• Less effective heating or cooling
• Increased fan load
• Poor air distribution

This does not mean high-efficiency filters are bad for HVAC systems.

It means the filter needs to be compatible with the system.

A facility manager should check the HVAC manufacturer's recommendations or work with a qualified HVAC professional before substantially increasing filter efficiency.

Where MERV Filtration Makes Sense

MERV filtration is particularly useful as part of the building's central HVAC system.

The HVAC already circulates air through:

• Return ducts
• Air handlers
• Supply ducts

Placing an appropriate filter in that airflow allows the system to remove particles whenever the HVAC fan operates.

MERV filters can therefore provide:

• Building-wide or zone-wide filtration
• Continuous HVAC particle control
• Protection for HVAC components
• A practical baseline of filtration

For many commercial buildings, a higher-quality HVAC filter is one part of the overall air-cleaning strategy.

Where HEPA Filtration Makes Sense

HEPA becomes especially useful when a building needs higher-efficiency particle removal at the room level.

A standalone HEPA air purifier does not require the central HVAC system itself to push air through the HEPA filter.

Instead, the air purifier has its own fan designed around the resistance of its filtration system.

That can make HEPA useful in:

• Offices
• Treatment rooms
• Waiting areas
• Classrooms
• Laboratories
• Commercial spaces
• Industrial environments
• Areas where supplemental filtration is needed

Our commercial HEPA air purifier guide covers this buying decision in more detail.

MERV 13 vs. HEPA

MERV 13 is frequently discussed for commercial buildings because it offers meaningful improvement in fine-particle capture over lower MERV filters.

EPA lists MERV 13 as having minimum average capture efficiency of:

• 50% or more for 0.3–1.0 micron particles
• 85% or more for 1.0–3.0 micron particles
• 90% or more for 3.0–10.0 micron particles

HEPA, by comparison, is rated at at least 99.97% at 0.3 microns.

That is a large difference in single-pass particle efficiency.

But the practical comparison should still consider:

• Where the filtration is installed
• How much air passes through it
• How often the air is filtered
• Whether the HVAC system can support the filter
• Whether supplemental room filtration is needed

A high-efficiency filter with very little airflow is not automatically better than a slightly less efficient system processing much more air.

Airflow Still Matters

Filtration efficiency is only one half of the equation.

The other half is how much air actually passes through the filter.

For a room air purifier, this means looking at:

• CFM
• Room volume
• Air changes per hour

For an HVAC system, it means considering the amount of system airflow that moves through the filter.

A HEPA purifier that is too small for the room may provide less useful room-level air cleaning than expected.

That is why filtration efficiency should always be evaluated alongside airflow.

For help matching an air purifier to room volume, see our commercial air purifier sizing guide.

TRACS also provides an air changes per hour calculator.

Can a Building Use MERV and HEPA Together?

Yes.

In many cases, this is the most practical way to think about the comparison.

Each system then does the job it was designed to do.

A dedicated HEPA purifier can add higher-efficiency filtration in areas where additional particle removal is wanted without requiring the central HVAC equipment to support a HEPA filter.

Why Some HEPA Systems Also Have MERV Pre-Filters

MERV and HEPA can also be used inside the same air purifier.

The MERV-rated filter can act as a pre-filter.

Its job is to capture larger particles before they reach the more expensive HEPA filter.

That can help reduce loading on the HEPA media.

For example, the TRACS TM1250 uses:

• A MERV 10 pre-filter
• H13 HEPA filtration rated at 99.99% efficiency at 0.3 microns
• In-unit UV-C

TRACS' TM500 and TM950 ceiling systems also use MERV 10 pre-filtration before their H13 HEPA filters.

This is a good example of why HEPA vs. MERV does not always have to mean HEPA or MERV.

The two filtration levels can perform different jobs within one system.

Does a Higher MERV Rating Always Mean a Better HVAC Filter?

Not necessarily for a particular HVAC system.

A higher MERV rating generally means greater particle-capture efficiency.

But the best HVAC filter is the highest appropriate efficiency that the system can support while maintaining the required airflow.

Putting an overly restrictive filter into a system that cannot handle it may create an airflow problem.

Commercial building owners should therefore consider both:

filtration efficiency + HVAC compatibility

rather than buying based only on the highest number.

What About MERV 8?

MERV 8 filters are common as pre-filters and in general filtration applications.

EPA's efficiency table shows MERV 8 is much more effective against larger particles than very small particles.

It is therefore not equivalent to HEPA and should not be presented as high-efficiency filtration for fine particles.

However, MERV 8 can still be useful as:

• A pre-filter
• HVAC component protection
• A first filtration stage

TRACS' TM250, for example, uses a MERV 8 carbon pre-filter before its H13 HEPA filter.

Again, the MERV filter and HEPA filter are doing different jobs.

HEPA vs. MERV for Different Commercial Needs

A simple way to make the decision is:

Our industrial HEPA air purifier guide explains higher-capacity systems in more detail.

See our ceiling HEPA air purifier guide for that configuration.

What Should a Commercial Building Compare?

When deciding between filtration options, look at:

For HVAC Filters

• Existing filter size
• Current MERV rating
• Manufacturer recommendations
• Filter resistance
• System airflow
• Replacement schedule

For HEPA Air Purifiers

• HEPA efficiency
• CFM
• Room volume
• Air changes per hour
• Filter sealing
• Installation type
• Maintenance

The question should not simply be:

Which filter has the higher efficiency?

It should be:

Which filtration setup gives this building the right combination of particle removal and airflow?

Filter Maintenance Matters

Both MERV and HEPA filters collect particles over time.

As filters load:

• Resistance may increase
• Airflow may change
• Filters eventually need replacement

Follow the manufacturer's maintenance recommendations rather than assuming a filter lasts indefinitely.

TRACS has a dedicated replacement filters and parts page for its HEPA systems and pre-filters.

How TRACS Uses MERV and HEPA Together

TRACS commercial systems do not treat MERV and HEPA as interchangeable.

Instead, several systems use staged filtration.

The pre-filter helps capture larger particulate material before air reaches the HEPA stage, while the HEPA filter provides much higher-efficiency particle filtration.

Businesses comparing these options can review the commercial air purifier systems available from TRACS.

Common Mistakes to Avoid

Calling HEPA "MERV 17"

HEPA is a separate filtration standard.

Assuming Every HVAC System Can Use HEPA

The HVAC system has to be designed for the filter's resistance and airflow requirements.

Choosing by Filter Efficiency Alone

Airflow also determines how much room air is actually cleaned.

Assuming MERV Filters Are Bad Because HEPA Is More Efficient

MERV filtration is extremely useful when used appropriately in HVAC systems and as pre-filtration.

Replacing a Filter Without Checking Compatibility

Higher efficiency can also mean different airflow resistance.

The Bottom Line

HEPA and MERV are both useful particle-filtration technologies, but they usually serve different roles.

MERV is primarily used to rate filters for general ventilation and HVAC systems.

HEPA provides a much higher level of particle filtration and is commonly used in dedicated air purifiers and specialized air-cleaning equipment.

For many commercial buildings, the practical answer is not:

HEPA or MERV?

It is:

Choose the filtration that fits the system rather than simply selecting the highest efficiency number.

Frequently Asked Questions