How to Assess Product Performance for Air Filters in Commercial Air Handling Units

Improving indoor air quality has become a top priority for commercial building owners, engineers, and facility managers. From protecting occupant health to supporting productivity and meeting evolving wellness expectations, air filtration within air handling units is now recognized as a core component of modern building performance—not an optional upgrade.

Air handling units play a central role in distributing conditioned air throughout a building. The filters installed within these systems determine how effectively airborne contaminants are removed before air reaches occupied spaces. Yet not all air filters deliver the same level of performance, durability, or compatibility with commercial HVAC systems.

The market is crowded with filtration products that promise cleaner air and healthier environments, but many rely on generalized claims that don’t translate to real-world commercial operation. Selecting the wrong filter can lead to restricted airflow, increased energy consumption, higher maintenance costs, or minimal impact on indoor air quality.

This guide is designed to help decision-makers assess product quality when evaluating air filters used in commercial air handling units. We’ll cover filtration standards, performance metrics, system compatibility, and verification criteria—so you can select solutions that deliver measurable improvement without compromising HVAC performance.

Why Air Filtration in Air Handling Units Matters in Modern Buildings

Indoor air quality challenges in commercial buildings differ significantly from those in residential environments. Commercial air handling units move large volumes of air continuously across multiple zones, serving high occupant densities and diverse spaces with varying risk profiles.

In offices, schools, healthcare environments, and other commercial facilities, airborne particles such as dust, pollen, allergens, bacteria, and viruses circulate through shared HVAC systems. Without effective filtration at the air handling unit, these contaminants can be redistributed throughout the building, impacting occupant comfort, health, and confidence in the workplace.

High-quality air filters installed in air handling units help:

• Reduce airborne contaminants before air enters occupied spaces
• Improve overall indoor air quality for employees, customers, and visitors
• Support healthier environments for individuals with asthma or respiratory sensitivities
• Enhance protection in shared indoor spaces where ventilation alone is insufficient
• Reinforce building wellness and risk mitigation strategies

Because air handling units operate continuously and serve entire buildings, filtration quality matters far more than in room-based applications. Evaluating filter performance—not just cost or brand recognition—is essential for long-term success.

What Air Filters in Air Handling Units Can — and Cannot — Do

Air filters installed in air handling units are one of the most effective tools for improving indoor air quality, but only when their capabilities and limitations are clearly understood. A common mistake is assuming that higher-rated filters automatically solve all air quality issues without considering system design.

Filtration technologies vary in how they capture airborne particles, address odors or gases, and impact airflow. Understanding what air filters are designed to do—and what they cannot replace—is key to assessing product quality.

What High-Quality Air Filters Do Well

Properly selected air filters in air handling units are effective at:

• Capturing airborne particles such as dust, pollen, mold spores, and allergens
• Reducing particulate load throughout the HVAC system
• Supporting healthier indoor environments by limiting exposure to bacteria and some viruses
• Improving comfort and air cleanliness across large indoor spaces

Filters rated for commercial use—such as higher MERV or HEPA configurations—are especially effective at removing fine particles that pose health risks when integrated correctly into AHUs.

What Filtration Cannot Replace

Even the highest-performing air filters are not a substitute for:

• Proper ventilation and outdoor air delivery
• Balanced airflow and correct system sizing
• A well-maintained HVAC system
• Routine inspection and filter replacement

Filtration works best as part of a comprehensive HVAC strategy. Performance depends on airflow rates, fan capacity, duct design, and operating schedules—not filtration media alone.

Understanding Airflow and Filter Integration in Air Handling Units

The effectiveness of any air filter is directly tied to airflow conditions within the air handling unit. Filters that are incompatible with system airflow can restrict air movement, reduce efficiency, and create uneven air distribution across the building.

Air filtration is not just about trapping particles—it’s about ensuring filtered air is delivered consistently and efficiently to all occupied spaces.

Why Airflow Matters

Poor airflow through an air handling unit can result in:

• Reduced contact time between air and filtration media
• Increased pressure drop and fan energy use
• Uneven filtration performance across zones
• Misleading assumptions about filter effectiveness

Airflow in AHUs is influenced by fan selection, duct configuration, filter depth, and loading characteristics. Filters must be selected with these variables in mind.

Integrated Filtration vs. Supplemental Devices

Air handling unit filtration provides whole-building coverage, unlike localized standalone devices. When properly designed, integrated filtration ensures that all conditioned air is filtered before distribution—making it the most scalable and consistent approach for commercial buildings.

Assessing System Compatibility

High-quality air filters should:

• Match the airflow rates and pressure limits of the AHU
• Maintain acceptable pressure drop as filters load
• Support even airflow distribution
• Operate without disrupting heating and cooling performance
• Align with operating schedules and maintenance capabilities

Filters that compromise airflow ultimately reduce system performance and negate air quality benefits.

Metrics That Indicate Filter Performance

Evaluating filter quality requires measurable performance data, not generalized claims. Reliable air filters are supported by standardized metrics that demonstrate how effectively they remove airborne contaminants.

Key Metrics to Evaluate

• MERV rating – Indicates particle capture efficiency across size ranges
• HEPA performance (where applicable) – Validated capture of 99.97% of particles ≥0.3 microns
• Pressure drop – Impact on airflow and fan energy
• Dust-holding capacity – How long filters maintain performance before replacement

These metrics allow engineers and facility managers to compare filters objectively under real operating conditions.

Why Testing and Certification Matter

Third-party testing verifies that filtration performance claims are accurate. High-quality manufacturers provide transparent documentation detailing test methods, airflow conditions, and performance limitations.

Types of Air Filters Used in Commercial Air Handling Units

No single filter type is ideal for every application. The most effective filtration strategies match filter technology to building use, risk profile, and system capability.

MERV-Rated Filters

MERV-rated filters are the most common filtration method in commercial air handling units.

• Lower MERV (8): Captures larger particles such as dust and pollen
• Mid-range MERV (11–13): Common balance of filtration and airflow
• Higher MERV (14–16): Increased protection with higher system demands

Proper selection is critical to avoid excessive pressure drop.

HEPA Filters in AHUs

HEPA filters provide the highest level of particle removal and are used in healthcare and controlled environments. Their integration requires careful system design to accommodate higher resistance and sealing requirements.

Gas-Phase and Carbon Filters

Used in AHUs to address odors, smoke, and chemical vapors. These filters supplement particulate filtration but do not replace it.

UV-C and Supplemental Technologies

Installed within air handlers to reduce pathogens on coils or in airflow. These systems complement—but do not replace—high-quality filtration.

Pros and Cons of Common Commercial Air Purification System Types

Air Purification Technology	Pros	Cons	Best Use Cases
HEPA Filtration Systems	• Captures extremely fine airborne particles (dust, allergens, bacteria, some viruses) • Widely recognized and validated performance standard • Strong improvement to indoor air quality • Effective for sensitive or high-risk occupants	• Higher pressure drop can impact airflow if not properly designed • Requires frequent filter replacement in high-load environments • Higher upfront and maintenance costs compared to standard filtration	Health care facilities, laboratories, schools, offices with high IAQ expectations, spaces with asthma or allergy concerns
MERV-Rated Filtration Systems	• Integrates easily with existing HVAC systems • Broad range of filtration levels (MERV 8–16) • Cost-effective baseline air purification • Widely used and well understood in commercial buildings	• Higher MERV ratings can restrict airflow if HVAC systems aren’t designed for them • Less effective than HEPA for very fine particles • Performance depends heavily on filter quality and installation	Offices, schools, retail spaces, general commercial facilities seeking improved air filtration without major system changes
Activated Carbon / Gas-Phase Filtration	• Effective at removing odors, smoke, and chemical vapors • Targets gases and VOCs that particle filters cannot capture • Improves comfort in odor-heavy environments	• Does not remove particulate matter on its own • Carbon media must be replaced regularly • Performance varies based on carbon volume and dwell time	Hair salons, commercial spaces with fumes, off-gassing materials, chemical or odor exposure
UV-C Pathogen Mitigation Systems	• Can inactivate bacteria, viruses, and germs • Works as a supplemental layer to filtration • No airflow restriction when properly installed	• Effectiveness depends on exposure time, lamp intensity, and placement • Does not remove particles or gases • Requires regular lamp maintenance and validation	Health care settings, high-occupancy spaces, buildings focused on infection control

Air Quality Metrics That Indicate Performance

When evaluating commercial air purification filters, one of the biggest challenges is separating measurable performance from vague marketing claims. Many products promise “cleaner air” or “healthier environments,” but without validated air quality metrics, those claims are difficult to verify or compare.

High-quality air purification systems are backed by clear, standardized performance indicators that demonstrate how effectively they remove airborne contaminants from indoor air.

Key Metrics to Look For

The most reliable systems provide data tied to recognized testing methods and standards, including:

• Clean Air Delivery Rate (CADR)
  • Indicates how much filtered air a system delivers per hour, helping quantify how quickly pollutants are removed from a space.
• Particle size capture efficiency
  • Shows how effectively the system removes fine airborne particles, including dust, pollen, and allergens.
• HEPA filtration performance
  • True HEPA filters are tested to capture at least 99.97% of particles down to 0.3 microns.
• Gas and odor reduction capability
  • Important for environments with smoke, chemical vapors, or off-gassing materials such as formaldehyde.

These metrics allow engineers and facility managers to assess how well a system will perform in real-world conditions—not just under ideal lab settings.

Why Certifications and Testing Matter

Independent testing and third-party certifications are critical indicators of product quality. They confirm that a system’s performance claims have been validated beyond manufacturer-controlled environments. When reviewing documentation, look for:

• Clearly defined test conditions
• Published standards or protocols used during testing
• Repeatable results across different operating conditions
• Transparency around limitations and use cases

Systems that lack this level of documentation may still operate, but they offer less confidence when deployed across commercial facilities with diverse air quality challenges.

Avoiding Common Performance Pitfalls

Not all air quality improvements are immediately visible. Some filter systems may reduce odors without addressing fine particles, while others capture dust but do little to mitigate bacteria or viruses. Assessing product quality means understanding exactly which pollutants the system targets and how that aligns with your building’s risk profile.

Reliable air quality metrics provide the foundation for informed decision-making—and help ensure that investments lead to meaningful improvements for occupants.

How to Verify Air Purification Claims From Manufacturers

One of the biggest challenges in evaluating air purification products is separating verified performance from marketing language. Many manufacturers promote bold claims about eliminating contaminants, improving health, or delivering the “highest level” of protection—yet provide little evidence to support those statements. Assessing product quality requires a critical review of how those claims are substantiated.

Look for Independent Testing and Documentation

High-quality air purification filters are supported by transparent, third-party testing. When reviewing manufacturer materials, buyers should expect access to:

• Published test reports tied to recognized standards
• Clearly defined test conditions and methodologies
• Measurable results for airborne particles, bacteria, or gases
• Data that aligns with real-world commercial operating conditions

Vague references to “lab-tested” performance without details are a red flag.

Understand What the System Was Tested For

Not all tests evaluate the same outcomes. Some focus on particle removal, while others measure pathogen inactivation or odor reduction. Verifying product quality means confirming that testing aligns with your specific needs—whether that’s reducing allergens, improving indoor air quality, or mitigating exposure to airborne pathogens.

Manufacturers should be able to explain:

• Which contaminants does the system targets
• What percentage reduction was achieved
• How performance changes with airflow and run time
• Any known limitations or exclusions

Be Cautious of Overstated Health Claims

Claims related to health benefits, virus elimination, or risk reduction should be supported by credible evidence. High-quality manufacturers avoid absolute language and instead provide data-driven explanations of how their systems contribute to cleaner indoor air.

If documentation is incomplete or overly promotional, it becomes difficult to assess whether the system will deliver consistent results in a commercial environment.

Verify Support and Accountability

Product quality extends beyond initial performance. Reputable manufacturers provide:

• Clear installation and operating guidelines
• Maintenance recommendations
• Access to technical support
• Replacement parts and filter availability

These factors help ensure that air purification filters continue to perform as expected long after installation.

Explore Proven Commercial Air Purification Solutions With Gil-Bar

Selecting a commercial air purification filter solution requires more than comparing product claims—it requires understanding performance data, system compatibility, and long-term reliability. Gil-Bar helps building owners and engineers evaluate, specify, and implement high-quality air purification solutions that deliver measurable improvements in indoor air quality.

If you’re assessing options for your facility, connect with Gil-Bar to explore vetted air purification technologies designed for real-world commercial performance. Let’s discuss your project, today.