Environmental Technology Verification
Test Report of Control of Bioaerosols in
HVAC Systems
Tri-Dim Filter Corporation
Predator II, Model 8VADTP123C23CCOOO
Prepared by
Research Triangle Institute
HRTI
INTERNATIONAL
Under a Contract with
U.S. Environmental Protection Agency
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THE ENVIRONMENTAL TECHNOLOGY VERIFICATION PROGRAM
&EPA HRTI
INTERNATIONAL
U.S. Environmental Protection Agency Research Triangle Institute
ETV Joint Verification Statement
TECHNOLOGY TYPE: VENTILATION MEDIA AIR FILTER
APPLICATION: FILTRATION EFFICIENCY OF BIOAEROSOLS IN
HVAC SYSTEMS
TECHNOLOGY NAME: Predator II, Model 8VADTP123C23CCOOO
COMPANY: Tri-Dim Filter Corporation
ADDRESS: 93 Industrial Drive, PO Box 466 PHONE: 800-458-9835
Louisa, VA 23093 FAX: 540-967-5430
WEB SITE: http://www.tridim.com
E-MAIL: b.duffv@tridim.com
The U.S. Environmental Protection Agency (EPA) has created the Environmental Technology
Verification (ETV) Program to facilitate the deployment of innovative or improved
environmental technologies through performance verification and dissemination of information.
The goal of the ETV Program is to further environmental protection by accelerating the
acceptance and use of improved and cost-effective technologies. ETV seeks to achieve this goal
by providing high quality, peer-reviewed data on technology performance to those involved in
the design, distribution, financing, permitting, purchase, and use of environmental technologies.
ETV works with recognized standards and testing organizations; stakeholder groups which
consist of buyers, vendor organizations, permitters, and other interested parties; and with the full
participation of individual technology developers. The program evaluates the performance of
innovative and improved technologies by developing test plans that are responsive to the needs
of stakeholders, conducting field or laboratory tests (as appropriate), collecting and analyzing
data, and preparing peer-reviewed reports. All evaluations are conducted in accordance with
rigorous quality assurance protocols to ensure that data of known and adequate quality are
generated and that the results are defensible.
EPA's National Risk Management Research Laboratory contracted with the Research Triangle
Institute (RTI) to establish a homeland-security-related ETV Program for products that clean
ventilation air. RTI evaluated the performance of ventilation air filters used in building heating,
ventilation and air-conditioning (HVAC) systems. This verification statement provides a
summary of the test results for the Tri-Dim Filter Corporation Predator II filter.
S-l
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VERIFICATION TEST DESCRIPTION
All tests were performed in accordance with RTFs "Test/Quality Assurance Project Plan:
Biological Testing of General Ventilation Filters," which was approved by EPA. Tests were
performed for the following:
• Bioaerosol filtration efficiency tests of the clean and dust-loaded filter. Three bioaerosols
were used in the testing:
o The spore form of the bacteria Bacillus atrophaeus (BG), a gram-positive spore-
forming bacteria elliptically shaped with dimensions of 0.7 to 0.8 by 1 to 1.5 //m,
o Serratia marcescens, a rod-shaped gram-negative bacteria with a size of 0.5 to 0.8
by 0.9 to 2.0 //m, and
o The bacterial virus (bacteriophage) MS2 dispersed as a micrometer-sized
poly disperse aerosol.
• American National Standards Institute (ANSI)/American Society of Heating,
Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 52.2-1999 test. The
test uses inert (potassium chloride (KC1)) particles for a filter when clean and through
five levels of dust loading. The filtration efficiency results (average of the minimum
composite efficiency) are given for three size ranges of particles: El, 0.3 to 1.0 //m; E2,
1.0to3.0//m; andE3, 3.0//mto 10//m.
• Inert aerosol filtration efficiency tests similar to the ASHRAE 52.2 test (0.3 to 10 |im)
but with extended fractional efficiency measurements down to 0.03 jim particle diameter
on a filter when clean and when fully dust-
loaded.
VERIFIED TECHNOLOGY DESCRIPTION
As shown in Figure 1, the Tri-Dim Filter Corporation
Predator II filter, Model 8VADTP123C23CCOOO, is a
4-panel V-cell filter with nominal dimensions of 0.61
by 0.61 by 0.30 m (24 by 24 by 12 in.). The glass
microfiber media is white.
VERIFICATION OF PERFORMANCE
Verification testing of the Tri-Dim Filter Corporation
Predator II filter began on June 21, 2004 at the test
facilities of RTI and was completed on July 22, 2004.
The results for the bioaerosol filtration efficiency tests
are presented in Table 1 for the clean and dust-loaded
filter. Table 2 presents the results of the ASHRAE 52.2 test. All tests were conducted at an air
flow of 0.93 mVsec (1970 cfm).
Figure 1. Photograph of the Tri-Dim Filter
Corporation Predator II filter.
S-2
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Table 1. Bioaerosol Filtration Results
Filter Condition
Clean
Dust loaded
Pressure Drop
Pa (in. H2O)
134 (0.54)
348(1.4)
Filtration
Efficiency for
Removal of
B. atrophaeus , %
94
99.8
Filtration
Efficiency for
Removal of
S. marcescens, %
95
99.9
Filtration
Efficiency for
Removal of
MS2 phage, %
96
99.7
Table 2. Summary of ASHRAE 52.2 Test
Filter
Tri-Dim Predator II
Filter
El
0.3 to 1.0 //m,
%
80
E2
1.0 to 3.0 //m,
%
98
E3
3.0 to 10 Aim,
%
99
Minimum Efficiency
Reporting Value
(MERV)
14 at 0.93m3/sec
(1970 cfm)
The quality assurance officer reviewed the test results and the quality control data and concluded
that the data quality objectives given in the approved test/QA plan were attained.
This verification statement addresses three performance measures of media air filters: filtration
efficiency for inert particles; removal efficiency for selected bioaerosols and pressure drop.
Users of this technology may wish to consider other performance parameters such as service life
and cost when selecting a media air filter for bioaerosol control. In accordance with the test/QA
plan1, this verification statement is valid for 3 years following the last signature added on the
verification statement.
Original signed by E. Timothy Oppelt, 9/16/04
E. Timothy Oppelt Date
Director
National Homeland Security Research Center
Office of Research and Development
United States Environmental Protection Agency
Original signed by David S. Ensor, 8/24/04
David S. Ensor
Director
ETV-HS
Research Triangle Institute
Date
NOTICE: ETV verifications are based on an evaluation of technology performance under specific, predetermined
criteria and the appropriate quality assurance procedures. EPA and RTI make no expressed or implied warranties
as to the performance of the technology and do not certify that a technology will always operate as verified. The
end user is solely responsible for complying with any and all applicable federal, state, and local requirements.
Mention of commercial product names does not imply endorsement.
so
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Environmental Technology Verification
Test Report of Filtration Efficiency of
Bioaerosols in HVAC Systems
Tri-Dim Filter Corporation
Predator II, Model 8VADTP123C23CCOOO
Prepared by:
Research Triangle Institute
Engineering and Technology Unit
Research Triangle Park, NC 27709
GS10F0283K-BPA-1, EPA Task Order 1101
RTI Project No. 08787.001
EPA Project Manager:
Bruce Henschel
Air Pollution Prevention and Control Division
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
September 2004
-------
Notice
This document was prepared by the Research Triangle Institute (RTI) with funding from the U.S.
Environmental Protection Agency (EPA) through the General Service Administration Contract
No. GS1OF0283K per EPA's BPA-1, Task Order 1101. The document has undergone RTF s
and EPA's peer and administrative reviews and has been approved for publication. Mention of
corporation names, trade names, or commercial products does not constitute endorsement or
recommendation for use of specific products.
Foreword
The Environmental Technology Verification (ETV) Program, established by the U.S.
Environmental Protection Agency (EPA), is designed to accelerate the development and
commercialization of new or improved environmental technologies through third-party
verification and reporting of performance. The goal of the ETV Program is to verify the
performance of commercially ready environmental technologies through the evaluation of
objective and quality-assured data so that potential purchasers and permitters are provided with
an independent and credible assessment of the technology that they are buying or permitting.
EPA's National Risk Management Research Laboratory contracted with the Research Triangle
Institute (RTI) to establish a homeland-security related ETV Program for products that clean
ventilation air. RTI developed (and EPA approved) the "Test/Quality Assurance Plan for
Biological Testing of General Ventilation Filters1." The test described in this report was
conducted following this plan.
Availability of Report
Copies of this verification report are available from
• Research Triangle Institute
Engineering and Technology Unit
PO Box 12194
Research Triangle Park, NC 27709-2194
• U.S. Environmental Protection Agency
Air Pollution Prevention and Control Division, E305-01
109 T.W. Alexander Drive
Research Triangle Park, NC 27711
Web site: http://www.epa.gov/etv/verifications
11
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Table of Contents
ETV Joint Verification Statement S-l
Notice ii
Foreword ii
Availability of Report ii
Table of Contents iii
Acronyms/Abbreviations iv
Acknowledgments v
1.0 Introduction 1
2.0 Product Description 1
3.0 Test Procedure 1
4.0 Bioaerosol Filtration Efficiency Calculation 4
5.0 Test Results 5
6.0 Limitations and Applications 7
7.0 References 7
Appendix: ASHRAE 52.2 Test Report 8
Figures
Figure 1. Photograph of the Tri-Dim Filter Corporation Predator II filter 1
Figure 2. Schematic of Test Duct 2
Figure 3. Summary of the Inert Aerosol Filtration Efficiency Data for the Clean and
Dust-Loaded Filter, # 2 6
Figure A-l. Filtration Efficiency and Flow Resistance for Tri-Dim Filter Corporation Predator II
filter 11
Tables
Table 1. Numbers of Filters and Expected Utilization 4
Table 2. Bioaerosol Filtration Results for Filter # 2 5
Table3. Summary of Removal Efficiency Using ASHRAE 52.2 Test for Filter # 1 6
Table 4. DQOs for Precision of Filtration Efficiency Measurements for Culturable Bioaerosol... 7
in
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Acronymns/Abbreviations
ANSI American National Standards Institute
ASHRAE American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.
ASME American Society of Mechanical Engineers
B Bacillus
BG Bacillus atrophaeus (formerly B. subtilis var niger and Bacillus globigif)
cfm cubic feet per minute
CPU colony forming unit(s)
cm centimeter
dso cutoff diameter, the aerodynamic diameter where the collection efficiency of the
sampler is 50%
DQO data quality objective
EPA U.S. Environmental Protection Agency
ETL SEMKO Electrical Testing Laboratories, Svenska Elektriska Materielkontrollanstalten AB
ETV Environmental Technology Verification
F Fahrenheit
fpm feet per minute
HS homeland security
in. inch(es)
KC1 potassium chloride
kPa kilopascal(s)
L liter(s)
MERV minimum efficiency reporting value
m meter(s)
mm millimeter(s)
mL milliliter(s)
min minute(s)
//m micrometer(s)
NAFA National Air Filtration Association
nm nanometer(s)
OPC optical particle counter
QA quality assurance
QC quality control
Pa pascal(s)
PFU plaque forming unit(s)
psig pounds per square inch gauge
RTI Research Triangle Institute
SAE Society of Automotive Engineers
SMPS scanning mobility particle sizer
IV
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Acknowledgments
The authors acknowledge the support of all of those who helped plan and conduct the
verification activities. In particular, we would like to thank Bruce Henschel, EPA's Project
Manager, and Shirley Wasson, EPA's Quality Assurance Manager, both of EPA's National Risk
Management Research Laboratory in Research Triangle Park, NC. We would also like to
acknowledge the assistance and participation of
• our stakeholder group for their input,
• Al Veeck and the National Air Filtration Association (NAFA), and Intertek ETL SEMKO
(Electrical Testing Laboratories, Svenska Elektriska Materielkontrollanstalten AB),
especially Theresa Peck, for their help in acquiring the filters, and
• Tri-Dim Filter Corporation for donating the filters to be tested.
For more information on the Tri-Dim Filter Corporation Predator II filter, contact
Bruce Duffy
Tri-Dim Filter Corporation
93 Industrial Drive
PO Box 466
Louisa, VA 23093
Tel: 800-458-9835
Fax: 540-967-5430
Email: b.duffy@tridim.com
For more information on RTFs ETV program, contact
Debbie Franke
Research Triangle Institute
POBox 12194
Research Triangle Park, NC 27709-2194
Telephone: (919) 541-6826
Email: dlf@rti.org
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1.0 Introduction
EPA's National Risk Management Research Laboratory contracted with the Research Triangle
Institute (RTI) to establish a homeland-security related ETV Program for products that clean
ventilation air. RTI convened a group of stakeholders representing government and industry
with knowledge and interest in the areas of homeland security and building ventilation. The
group met in December 2002 and recommended technologies to be tested. RTI then developed
(and EPA approved) a test plan. Reports from the first series of tests can be found at
http://www.epa.gov/etv/verifications/vcenterlO-l.html. There are four filters in the second series
of tests. The tests described in this report were conducted following Version 2 of the
"Test/Quality Assurance Plan for Biological Testing of General Ventilation Filters1."
2.0 Product Description
As shown in Figure 1, the Tri-Dim Filter Corporation
Predator II filter, Model 8VADTP123C23CCOOO, is a
4-panel V-cell filter with nominal dimensions of 0.61
by 0.61 by 0.30 m (24 by 24 by 12 in.). The glass
microfiber media is white.
3.0 Test Procedure
The test program measured the culturable bioaerosol
removal efficiency of general ventilation filters. Three
tests were required to accomplish this goal. First, the
American Society of Heating, Refrigerating and Air-
Conditioning Engineers, Inc. (ASHRAE) Standard
52.22 test was performed on one filter of the test filter R L phot h of the Tri.Dim
^ivf^11?,! ^ ™7*f?° H LeP°±n!vf ^ Filter Corporation Predator II filter.
(MERV) of the filter. ASHRAE designed the MERV to
represent a filter's minimum performance over multiple particle sizes in the 0.3 to 10 |j,m range
and the filters tested under ASHRAE 52.2 can range from MERV 5 to 16. In general, a higher
MERV indicates higher filter efficiency. For reference, clean room HEPA and ULPA filters are
rated at between MERV 17 and 20. Most commercial filters and high end home filters are now
marketed using the MERV. After determining the MERV, the biological test using three
different bioaerosols and an inert aerosol test were performed on a second filter. This test
extended the standard 52.2 test down to 0.03 |j,m and included both clean and fully dust-loaded
conditions. All tests were at an air flow rate of 0.93 mVsec (1970 cfm) to conform to the
conditions described in ASHRAE Standard 52.2.
All testing was performed in a test duct as specified in ASHRAE Standard 52.2. A schematic of
the test duct is shown in Figure 2. The test section of the duct is 0.61 m (24 in.) by 0.61 m (24
in.) square. The locations of the major components, including the sampling probes, device
section (filter holder), and the aerosol generator (site of aerosol injection) are shown.
The inert testing and the ASHRAE Standard 52.2 test were performed using a solid-phase (i.e.,
dry) potassium chloride (KC1) aerosol. The filters were loaded using ASHRAE dust, composed
of 72% Society of Automotive Engineers (SAE) fine, 23% powdered carbon, and 5% cotton
linters. The final pressure drop was determined by the Standard's requirements.
1
-------
Room
Air
Exhaust
to
Room
X
6
it ASME
NOZZ!G
Outlet Filter Bank . Downstream Mixer
i Biological \
1 1 Sampling ^
1^ If r< i
t I \ <3
^ ^ '|^
%
)
Si Device Backup
m Section Filter
Flow Control
Valve
Aerosol
Generator
Biological
Sampling
Figure 2. Schematic of test duct. Filter is placed in device section.
The bioaerosol tests were conducted using three microorganisms, including two bacteria and one
bacterial virus. The spore form of the bacteria Bacillus atrophaeus (formerly B. subtilis var
niger and Bacillus globigii or BG) was used as the surrogate for gram-positive spore-forming
bacteria. The BG spore is elliptically shaped with dimensions of 0.7 to 0.8 by 1 to 1.5 //m.
Serratia marcescens was used as the surrogate for rod-shaped gram-negative bacteria. S.
marcescens is 0.5 to 0.8 by 0.9 to 2.0 //m.
The bacterial virus (bacteriophage) MS2 (0.02 to 0.03 //m), having approximately the same
aerosol characteristics as a human virus, was used as a surrogate for the viruses of similar and
larger size and shape. Although the individual virus particles are in the submicrometer size
range, the test particle size for the virus tests spanned a range of sizes (polydispersed bioaerosol).
This test was not designed to study the removal efficiencies for single individual virus particles;
rather, it was designed to determine the removal efficiencies for virus particles as they are
commonly found indoors. A representative challenge would be a micrometer-sized,
polydispersed aerosol containing the phage because:
• The aerosols created from sneezing and coughing vary in size from < 1 to > 20 //m, but the
largest particles settle out and only the smaller sizes remain in the air for extended periods for
potential removal by an air cleaner3;
• Few viruses have been found associated with particles less than 1 //m4; and
• Nearly all 1 to 2 //m particles are deposited in the respiratory tract, while larger particles may
not be respired.
Bacteria suspension preparation for the aerosolization process required that the specific test
organism be grown in the laboratory and the suspension prepared for aerosol generation in the
test rig. The microbial challenge suspensions were prepared by inoculating the test organism on
solid or liquid media, incubating the culture until mature, wiping organisms from the surface of
the pure culture (if solid media), and eluting them into sterile diluent to a known concentration.
2
-------
The bacterial virus challenge was prepared by inoculating a logarithmic phase broth culture of
the host bacteria with phage and allowing it to multiply until the majority of the host bacteria
were lysed. The mixture was centrifuged to remove the majority of the cell fragments. The
resultant supernatant was the phage stock and was used as the challenge aerosol. The
concentration of the phage stock was approximately 1 x 109 or higher plaque forming units per
milliliter, (PFU) /mL.
The challenge organism suspensions were aerosolized using a Collison nebulizer (BGI,
Waltham, MA) at 103.4 kPa (15 psig) air pressure. The nebulizer generates droplets with an
approximate volume mean diameter of 2 //m. The nebulizer output stream was mixed with
clean, dry air to create the dry aerosolized microbial challenge. The particle diameter after the
water evaporates depends on the solids content of the suspension. The resulting particle size of
the B. atrophaeus and the S. marcescens in the air stream entering the test filter was believed to
be that of single organisms (singlets). The MS2 aerosol consisted of poly dispersed micrometer-
sized particles, each containing numerous organisms, as discussed previously.
Upstream and downstream sampling of the bacteria was accomplished using a one-stage
Andersen viable bioaerosol sampler. The one-stage Andersen sampler is a 400-hole multiple-jet
impactor operating at 28 L/min. The cutoff diameter (dso) is 0.65 //m - the aerodynamic
diameter where the collection efficiency of the sampler is 50%. After sampling, the petri dishes
were removed from the sampler and incubated at appropriate times and temperatures for the test
organism being used. Colony forming units (CPUs) were then enumerated and their identity
visually confirmed. A positive hole correction was used to adjust colony counts from the
Andersen multiple-hole impactor for the possibility of collecting multiple colonies through a
hole5.
The microbial viruses were collected in AGI-30s. The AGI-30 is a high velocity liquid impinger
operating at a flow rate of 12.3 to 12.6 L/min. The dso is approximately 0.3 //m. The AGI-30 is
the sampler against which the other commonly used bioaerosol samplers are often compared.
For the inert KC1 aerosol filtration efficiency measurements, the particle sizing measurements
were made with two particle counting instruments: a Climet model 500 spectrometer/optical
particle counter (OPC) covering the particle diameter size range from 0.3 to 10 //m in 12 particle
sizing channels and a TSI scanning mobility particle sizer (SMPS) to cover the range from 0.03
to 0.5 //m. Depending upon the quality of the data from any individual test, the SMPS can
sometimes reliably quantify particles even smaller than 0.03 //m, and when this is the case, those
smaller sizes are reported here. The ability to quantify sizes smaller than 0.03 //m is determined
as defined in Table A2 of the test/QA plan. According to the test/QA plan, a data control
parameter for the SMPS requires that the standard deviation on upstream counts be computed for
each efficiency test based on the upstream particle counts and that the standard deviation be less
than 0.30 before the data are used. The lower size ranges for the SMPS are included in the
verification report only if they meet the data control parameter.
Quality Control (QC) procedures for running the test duct and the measuring equipment are
defined in the test/QA plan.
3
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The filters to be tested were obtained directly from the vendor's warehouse by Intertek ETL
SEMKO - an independent organization recommended by the industry - on June 7, 2004
following the NAF A Product Certification Program Procedural Guide6. A minimum of four
filters were procured, and were sent to RTI. The four filters were used as shown in Table 1.
Full details of the test method can be found in RTFs test/QA plan1.
Table 1. Numbers of Filters and Expected Utilization
Tests
ASHRAE Standard 52.2 test (0.3 to 10 pm)
Initial efficiency for an inert aerosol (0.03 to 10 |j,m)
Initial efficiency for three bioaerosols
Dust load to final pressure drop with ASHRAE dust
Efficiency for inert aerosol after dust-loading (0.03 to 10 |j,m)
Efficiency for three bioaerosols after dust-loading (0.03 to 10 |j,m)
Reserve filtera
Filter #
1
X
2
X
X
X
X
X
3
X
4
X
Tillers # 3 and # 4 have been kept in reserve to be used if needed.
4.0 Bioaerosol Filtration Efficiency Calculation
Bioaerosol samples were collected simultaneously using multiple samplers. A minimum of six,
usually twelve, replicates were collected for each efficiency determination.
The mean upstream and downstream CFUs were calculated as:
U =
i=\
and
D =
i=\
(1)
n
n
where:
D; = Downstream count of the ith sample and n is the number of replicate samples
collected and
U;= Upstream count of the ith sample and n is the number of replicate samples
collected.
The calculation of the penetration was based on the ratio of the downstream to upstream
culturable counts. The penetration with the filter installed in the test rig (Pmeasured) is shown in
the following equation:
where:
P.
D
(2)
measured
U
-------
D = Mean downstream count with a filter installed in the test rig and
^ = Mean upstream count with a filter installed in the test rig.
The PIOO (no filter installed in the test rig) was calculated as the Pmeasured but using the results of
the no filter tests.
MOO ~~
-D
100.
/u
(3)
100
where:
Dioo = Mean downstream count with no filter in the test rig and
C/ioo = Mean upstream count with no filter in the test rig.
To remove system bias, the Pmeasured is corrected by the penetration of a blank "no filter" test for
D , rmeasured.
± corrected - /
Pwo
(4)
which no air cleaner is installed in the duct (Pioo).
The filtration efficiency is then calculated as shown in Eq. 5.
Filtration Efficiency (%) = 100(1- Pcorrected)
(5)
The DQOs are the 95% confidence interval and were calculated based on the
standard deviation of the Pmeasured penetration computed from the coefficient of variance of
upstream and downstream culturable counts of as shown in Eq. 6.
Combined Std . Deviation = P measur
ed
+
(6)
where:
= Penetration calculated from the upstream and downstream culturable counts,
CVu = Coefficient of variance for the upstream Pmeasured counts, and
CVD = Coefficient of variance for the downstream Pmeasured counts.
5.0 Test Results
The bioaerosol filtration efficiency results are found in Table 2.
Table 2. Bioaerosol Filtration Results for Filter # 2
Filter
Condition
Clean
Dust-loaded
Pressure
Drop
Pa (in. H2O)
134 (0.54)
348(1.4)
Filtration
Efficiency for
Removal of
B. atrophaeus, %
94
99.8
Filtration
Efficiency for
Removal of
S. marcescens, %
95
99.9
Filtration
Efficiency for
Removal of
MS2 phage, %
96
99.7
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The ASHRAE filtration efficiencies and the MERV are shown in Table 3. The filtration
efficiencies (average of the minimum composite efficiency) are presented by particle size
groupings: El, 0.3 to 1.0 //m; E2, 1.0 to 3.0 //m; and E3, 3.0 //m to 10 //m. The full ASHRAE
52.2 test results are provided in the Appendix.
The filtration efficiency for inert particles is plotted so that the efficiencies for particles from
about 0.03 to 10 //m can be observed (Figure 3). Note that this is a logarithmic (base 10) scale
on the X axis. Two instruments were used to obtain the measurements. The SMPS was used to
measure particles up to 0.5 //m and the OPC was used for particles from 0.3 to 10 //m. There is
good agreement in the size range covered by both instruments. These measurements were made
on a filter when clean and then when dust-loaded.
Table 3. Summary of Removal Efficiency Using ASHRAE 52.2 Test for Filter # 1
Filter
Tri-Dim Predator II
El
0.3 to 1.0 Aim,
80
E2
1.0 to 3.0 Aim,
98
E3
3.0 to 10 Aim,
99
MERV
14 at 0.93m3/sec
(1970 cfm)
100
80
60
20
A
SMPS-loaded
0.01 0.10 1.00
Particle Diameter (^m)
10.00
Figure 3. Summary of the Inert Aerosol Filtration Efficiency Data for the Clean and Dust Loaded
Filter, #2
The quality assurance officer has reviewed the test results and the quality control data and has
concluded that the data quality objectives (DQOs) (Table 4) given in the approved test/QA plan
have been attained. The DQOs do not include the variabilities associated with the no-filter
(PI00) measurements or the positive hole correction.
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Table 4. DQOs for Precision of Filtration Efficiency Measurements for Culturable Bioaerosol
Data quality objective
Precision of filtration
efficiency, %
Test organism
Spore-forming bacteria
(B. atrophaeus)
±8a
Vegetative bacteria
(S. marcescem)
±lla
Bacterial virus
(MS2 phage)
±13a
a 95% confidence level, based on the standard deviation of penetration computed from the
coefficient of variance upstream and downstream Pmeasured culturable counts.
6.0 Limitations and Applications
This verification report addresses three performance measures of media air filters: filtration
efficiency for inert particles; removal efficiency for selected bioaersols and pressure drop.
Users may wish to consider other performance parameters such as service life and cost when
selecting a general ventilation air filter for their application.
In accordance with the test/QA plan1, this verification statement is valid for 3 years following the
last signature added on the verification statement.
7.0 References
1. RTI. 2004. Test/QA Plan for Biological Testing of General Ventilation Filters, Version 2.
Research Triangle Institute, Research Triangle Park, NC.
2. ANSI/ASHRAE Standard 52.2-1999, Method of Testing General Ventilation Air-Cleaning
Devices, American National Standards Institute/American Society of Heating, Refrigerating
and Air-Conditioning Engineers, Atlanta, GA.
3. Knight, V. 1973. Viral and Mycoplasmal Infections of the Respiratory Tract, Lea & Febiger,
Philadelphia, PA.
4. Buckland, F.E., and Tyrell, D.A.S. 1962. Loss of Infectivity on Drying Various Viruses,
Nature 195: 1063-1064.
5. Macher, J.M. 1989. Positive Hole Correction of Multiple-jet Impactors for Collecting Viable
Microorganisms, American Industrial Hygiene Association Journal. 50: 561-568.
6. NAFA (National Air Filtration Association). 2001. Product Certification Program
Procedural Guide Approved Version 1, Second Revision, February 2001. Virginia Beach,
VA.
-------
Appendix ASHRAE 52.2 Test Report
For Tri-Dim Filter Corporation Predator II Filter
ASHRAE 52.2 TEST REPORT
Manufacturer: Tri-Dim Filter Corporation
Product Name: Predator II
RTI Report No. AY07130401
Test Laboratory:
RTI
3040 Cornwall is Road
Research Triangle Park, NC 27709
919-541-6941
mko@rti.org
8
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Page 1 of 3
ASHRAE Std. 52.2 Air Cleaner Performance Report Summary
This report applies to the tested device only.
Laboratory Data
RTI Report No.
Test Laboratory
Operator
Particle Counter(s):
AY07130401
Date
7-13-04
Research Triangle Institute
Clayton
Brand Climet
Supervisor Owen/Hanley
Model 500
Device Manufacturer's Data
Manufacturer
Product Name
Product Model
Test requested by
Sample obtained from
Catalog rating:
Specified test conditions:
Device Description
Nominal Dimensions (in.):
Generic name
Amount and type of adhesive
Other attributes
Test Conditions
Airflow (cfm)
Face Velocity (fpm)
Test aerosol type:
Remarks
Resistance Test Results
Initial resistance (in. wg)
Tri-Dim Filter Corporation
Predator II
8VADTP123C23CCOOO
ETV
ETV
Airflow rate
Airflow (cfm)
Face Velocity (fpm)
NA
1970
Initial dP (in. wg)
Final dP (in. wg)
493
24x24x12
VCell
(height x width x depth)
Media color
White
NA
2 V Cells
1970
Temperature (F)
74
493
Final Pressure Drop (in. wg)
1.40
KCI
Plastic Frame
0.51
Final resistance (in. wg)
NA
1.40
46
1.40
Minimum Efficiency Reporting Data
Composite average efficiencies
Air cleaner average Arrestance per Std 52.1:
E1
80
Minimum efficiency reporting value (MERV) for the device:
E2
98
NA
E3
99
14 @ 1970
cfm
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Report No. AY07130401
Research Triangle Institute
100
Nominal Dimensions (in
90-
Final Resistance (ii
80 -
— . 70 - -
Min. Diaift* (|jml
Max. Dia& (|jffl?
o
'o
E 50
2
40 --
30
20 --
10 --
0.1
-•-Initial Efficiency
-•-After 1st loading
-A-After 2nd loading
-•-After 3rd loading
-*- After 4th loading
-A-After 5th loading
Particle Diameter
(fpm)
(m/s)
10
(in. H2O)
(Pa)
.. 100
90
>- 70
o
§ 60
'o
it 50
LU
.1 4°
"ro 30
E 20
10
Minimum Composite Curve
0.1 1
Particle Diameter (urn)
10
0.8
O
(N
I
gO.6
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TABULATED DATA SUMMARY
Report No. AY07130401
Research Triangle Institute
Summary of Test Conditions:
Product Manufacturer
Product Name
Nominal Dimensions (in.)
Airflow (cfm)
Final Resistance (in. H2O)
Tri-Dim Filter Corporation
Predator II
24x24x12
1970
1.40
OPC Channel Number
Min. Diam. (urn)
Max. Diam. (urn)
Geo. Mean Diam (urn)
Efficiency (%) per Indicated Size Range
1
0.3
0.4
0.35
2
0.4
0.55
0.47
3
0.55
0.7
0.62
4
0.7
1
0.84
5
1
1.3
1.14
6
1.3
1.6
1.44
7
1.6
2.2
1.88
8
2.2
3
2.57
9
3
4
3.46
10
4
5.5
4.69
11
5.5
7
6.20
12
7
10
8.37
Initial efficiency
after first dust load
after second dust load
after third dust load
after fourth dust load
after fifth dust load
Run No.
AY071 30402
AY071 30403
AY071 30404
AY071 30405
AY071 40401
AY071 40402
70
76
88
94
96
98
76
83
93
96
98
98
84
90
96
98
99
99
91
95
98
99
99
99
96
98
99
99
100
100
98
99
99
100
100
100
99
100
100
100
100
100
99
99
100
100
100
100
99
100
100
100
100
100
99
100
100
100
100
100
99
100
100
100
100
100
99
100
100
100
100
100
Minimum Composite Efficiency
70 76
84
91
96 98 99 99 99 99 99 99
E1 =
E2 =
E3 =
80
98
99
(E1 is the average of the minimum composite efficiency values for particle diameters from 0.3 to 1 urn.)
(E2 is the average of the minimum composite efficiency values for particle diameters from 1 to 3 urn.)
(E3 is the average of the minimum composite efficiency values for particle diameters from 3 to 10 urn.)
MERV= 14
Resistance to Airflow for clean filter: 0.93 m3/s (1970 cfm)
Airflow
50
75
100
125
Airflow
(m3/s)
0.46
0.70
0.93
1.16
Airflow
(cfm)
985
1478
1970
2463
Air Velocity
(fpm)
246
369
493
616
Air Velocity
(m/s)
1.25
1.88
2.50
3.13
Resistance
(in. H2O)
0.22
0.35
0.51
0.67
Resistance
(Pa)
55
87
126
167
Resistance to Airflow with Loading at 0.93 m3/s (1970 cfm)
Resistance Resistance
(in. H2O) (Pa)
Initial
After first dust load
After second dust load
After third dust load
After fourth dust load
After fifth dust load
0.51
0.55
0.73
0.95
1.18
1.40
126
136
181
237
293
348
Weight Gain of filter after completion of dust loading steps
11
100.3 g
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