Modified ASHRAE 52.2 Duct Testing for In-Duct and In-Sequence Air Purification Systems
Airmid Healthgroup’s Modified ASHRAE 52.2 duct rig system is attached to an ASTM/AHAM environmental test chamber, enabling comprehensive assessment of in-duct and in-sequence air purifying systems on real-world bio-particulates — going far beyond standard particle filtration testing.
What Bio-Particulates Can Be Measured?
The Modified ASHRAE 52.2 system is capable of measuring a wide range of biological particulates using the most sophisticated immunoassay and molecular biological techniques available, including:
Pathogens
Viral particles, bacteria, and fungi/moulds at sub-micron, standard, and nano-particle size ranges.
Allergens
House dust mite, various pollens, animal dander (cat/dog), and particular toxins found in real household environments.
Real Household Dusts
Known quantities of real household dusts and particulates greater than 10 microns, sub-micron, and nano-particle sizes.
Products That Can Be Tested
- Air Cleaning Devices
- HVAC Filters
- HVAC Systems
- Building Management Systems
- Central Vacuum Cleaners
How the Modified ASHRAE 52.2 System Works
The system recirculates air through the chamber and back into the ducting on a repeated basis, with a range of fresh air flow dilution rates — accurately replicating the conditions found in real homes and offices.
Monitoring involves proximal and distal biological air sampling for selected organisms within the ducting system, with the option for air and surface sampling in the chamber before and after each air change. Surface sampling can also be requested.
For air cleaning devices designed for placement in the room itself, bio-particulates can be introduced directly into the chamber or through the ducting, with an option to recirculate air or not.
This approach generates data on actual bio-particulates and evaluates the real impact of air cleaning systems in a way that standard particle-only testing cannot replicate.
Why This Testing Matters
Air cleaning within ducting systems presents a highly efficient opportunity to clean the air at source. Introducing new technologies into ducting for the purpose of maintaining particle-free air represents both a challenge and a significant commercial opportunity.
Many studies performed by Airmid Healthgroup have led to a complete re-evaluation of product performance and service intervention impacts — with results frequently proving pivotal in driving design improvements. Airmid not only conducts the studies but brings conclusions to the attention of the medical and scientific community through peer-reviewed publications and industry presentations.
About iAIR Labs
Airmid Healthgroup is a world-leading contract research laboratory, accredited to ISO/IEC 17025:2017 by the Irish National Accreditation Board (INAB, Reg. No. 284T) for specific allergen testing methods including cat (Fel d 1) and house dust mite (Dermatophagoides pteronyssinus, Der p 1).
From airborne pathogen testing and indoor air quality validation to antimicrobial surface and textile efficacy studies, we provide the independent data and scientific validation that innovators need to meet regulatory requirements, accelerate product development, and earn consumer confidence.
Trusted globally by medtech, consumer product, and building technology leaders, our advanced bioaerosol chamber facilities and expertise in microbiology, virology, allergens, and aerobiology enable real-world performance testing to the highest international standards — including ASHRAE 241, AHAM AC-5, ISO 16000, ISO 18184, and ASTM E3135.
Frequently Asked Questions
What is the difference between standard ASHRAE 52.2 and the Modified ASHRAE 52.2 duct test?
Standard ASHRAE 52.2 measures a filter’s efficiency against inert particles to assign a MERV rating. The Modified ASHRAE 52.2 duct system goes further — using real biological particulates such as viruses, bacteria, allergens, and fungi to assess how air cleaning technologies perform against the actual contaminants found in homes and offices.
Can both in-duct systems and standalone room air cleaners be tested?
Yes. The system accommodates both in-duct and in-sequence air purifying technologies, as well as standalone room air cleaning devices where bio-particulates can be introduced directly into the chamber or via the ducting system.
What size particles can the system detect?
The system captures particulates across all relevant size ranges — including those greater than 10 microns, sub-micron particles, and nano-particles — providing a comprehensive picture of air cleaning performance.
Is surface sampling available in addition to air sampling?
Yes. In addition to proximal and distal air sampling within the ducting system, surface sampling in the chamber can be included upon request — both before and after air changes.
How does this testing help with product development?
Results from Modified ASHRAE 52.2 testing have frequently been pivotal in identifying performance gaps and driving design improvements. The data generated gives development teams precise, real-world evidence of how their technology performs — information that standard particle testing alone cannot provide.
