1. Air Filtration and Indoor Air Quality Panel Discussion
Moderator: Jim Rosenthal, CAFS
Panelists: Bobby Singer, Blue Heaven Technologies, CAFS John Zhang, 3M Company
Michael Waring, PhD, Drexel University

2. Filter Testing Using the ASHRAE 52.2 Protocol
Bobby Singer, CAFS Blue Heaven Technologies
Copyright © M

3. Current Document

5. ASHRAE 52.2 Metrics for laboratory comparisons …..
1/28/2018 3:32 AM
ASHRAE 52.2 Metrics for laboratory comparisons …..
Resistance to Air Flow – “w.g.
Efficiency by Particle Size - %
.3 to 10 Microns
12 “bands” to construct “MERV”
Arrestance of loading dust - %
Dust Holding Capacity - grams
To a prescribed final resistance
© 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

6. Overview understanding the objective …..
Specific to Air Filter Performance
Benchmarking
Controlled environment
“Perfect” conditions
NOT a direct predictor of IAQ

7. Typical Report Page 1 E1, E2 and E3 Flow Rate Clean Resistance
Final Resistance
MERV

8. Typical Report
Page 2
“RT” Curve
Six efficiencies
“Composite”

9. Typical Report
Page 3
All tabular
“RT” at Flow Rate
Composite Min. !

11. Typical Empty Duct Correlation

12. System Qualifications – “What”
A Key to Proper Testing

13. Courtesy – Mike Corbat, Custom Filter - 2015 AFS

14. Ambient Conditions – New!
A Key to Proper Testing

15. From the horses mouth……
Standard 52.2 was developed so that both users and specifiers can compare products, predict a uniform level of known performance under operating conditions with reason- able certainty, and determine appropriate air-cleaner efficiencies for specific situations.
Not an Application Standard
Users should not misinterpret the intent of this standard. This is a test method standard, and its results are to be used to directly compare air cleaners on a standardized basis irre- spective of their applications
1. PURPOSE
This standard establishes a test procedure for evaluating the performance of air-cleaning devices as a function of particle size.

16. So Many Questions Bobby Singer Blue Heaven Technologies 502-357-0132

17. Air Filtration and Indoor Air Quality Panel Discussion
John Zhang, Ph. D 3M Company
Copyright © M

18. Impact of Filtration on Indoor Air
Outline
Indoor Particulates
Micro-particle Filtration
Performance of Residential HVAC Filters
Impact of Filtration on Indoor Air Quality
3M Copyright 2016

19. 10 mg/m3 increase => 0.35 years reduction in life expectancy
Indoor PM2.5 Pollution
PM2.5 pollution
10 mg/m3 increase => 0.35 years reduction in life expectancy
3M Copyright 2016

20. Why MPR (Micro-Particle Rating)
Ignored for MERV 12 or less
MPR is a rating system for filters performance in the micro-particle size range (particle size < 1 micron).
99% of respirable particles (smoke, aerosol, bacteria, virus, allergens, fine dust) are smaller than 1mm.
Micro-particles have significant adverse health impact.
Filter efficiency for micro-particles (<1 micron) is excluded in the MERV rating for MERV 12 or lower filters.
3M Copyright 2016

21. Filter Performance 3M Copyright 2016 Particle Size, µm 0.001 0.01 0.1
1.0 10
100
Tobacco Smoke
Bacteria
Virus
Pollens
Fungi
Oil Smoke
Pet dander
Human Hair
Visible
Invisible
PM2.5
Dust mite allergens
Household dust
Human Hair: > 60 mm
Pollens: 0.8 – 40 mm
Pet dander: 0.5 –10 mm
Dust mite allergens : 0.8 – 40 mm
Household dust: 0.1 – 10 mm
Fungi: 0.5 – 5 mm
Bacteria: 0.3 – 10 mm
Cooking smoke: 0.05 – 1 mm
Tobacco smoke: 0.01 – 1 mm
Virus: – 0.1 mm
2.5
3M Copyright 2016

22. Effectiveness of Air Filters
CONTAM IAQ model developed by NIST, considering factors such as:
Filter performance
Ambient aerosol concentration
Building structure, infiltration etc
Indoor particle sources and sinks
Summary
Indoor airborne particulates are mostly micro-particles (<1 microns)
Filters can effectively reduce indoor airborne particles.
The reduction is governed by filter performance in the micro-particle size range.
3M Copyright 2016

23. John Zhang 3M Company zzhang2@mmm.com
Panelist Contact Information
John Zhang 3M Company
3M Copyright 2016

24. Air Filtration and Indoor Air Quality Panel Discussion
Michael S. Waring Associate Professor Director of Architectural Engineering Civil, Architectural and Environmental Engineering at Drexel University
Copyright © 2016 NAFA

25. How effective are filters?
We know that filters CAN remove PM efficiently…
ASHRAE 52.2 tests PM > 0.3 μm
Ultrafine PM (< 0.1 μm) is removed well by some filters
However, efficiency does not indicated how effective filters are at removing PM indoors
Function of building and climate
Hecker and Hofacre (2008)

26. What are the driving factors?
Building and climate can impact effectiveness due to:
HVAC airflow paths (residential or commercial)
Impacts size of particles contacting filter
Impacts amount of outdoor versus recirculated air
HVAC runtime (residential or commercial)
Residential HVAC operation on duty cycle dictated by loads
Commercial HVAC operation is largely continuous
Filter installation goodness
Potential for HVAC filter airflow bypass

27. Residential vs. commercial airflows
Waring & Siegel (2008)

28. Size of particles contacting filter
Office PM distributions
Residential PM distributions
Mass Conc.
Mass Conc.
PM2.5
PM10
PM2.5
PM10
Riley et al. (2002)

29. Office and residential AERs
recirculation
Infiltration AER
Office: 0.35 h-1 (2.1)
Res: 0.44 h-1 (2.04)
Ventilation AER
Office: 1.13 h-1 (2.59)
Res: 0 h-1
Recirculation AER
Office: 3.25 h-1 (2.2)
Res: 1.4 h-1 (1.9)
= 5.7 h-1 (1.3) × (1.9) O
ventilation R O
infiltration O R
Chan (2006); Rackes and Waring (2013, 2015); El Orch et al. (2014)

30. Understanding parameter impacts
PM2.5 I/O ratio can show impacts of filter efficiency:
penetration
factor = 0.9
infiltration
AER (O & R)
filter efficiency
from 0.1 to 0.9
ventilation
AER (O only)
deposition
rate = 0.1 h-1
infiltration
AER (O & R)
ventilation
AER (O only)
filter efficiency
from 0.1 to 0.9
recirculation
AER (O & R)

31. Understanding parameter impacts
10,000 iterations were run to compute I/O ratios
Regressions w/ standardized regression coefficients (SRC)
SRCs are coefficients standardized so that the variances of dependent and independent variables are 1 – show influence of inputs

32. Panelist Contact Information
Michael S. Waring Civil, Architectural and Environmental Engineering at Drexel University