ngineering Issue
United States
Environmental Protection
Agency
¦
Adsorption-based Treatment Systems for
Removing Chemical Vapors from Indoor Air
The U.S. Environmental Protection Agency (EPA)
Engineering Issue Papers (EIPs) are a series of
technology transfer documents that summarize the
latest information on selected waste treatment and
site remediation technologies and related issues. EIPs
are designed to help remedial project managers, on-
scene coordinators, contractors and other site
managers understand the type of data and site
characteristics needed to evaluate a technology for a
particular application at their sites. This EIP may also
be useful for building owners/operators and home
owners who may have a concern about the indoor air
quality at their location(s). Each EPA EIP is
developed in conjunction with a small group of
engineers and scientists from inside EPA and outside
consultants, with a reliance on peer-reviewed
literature, EPA reports, Web sources, current ongoing
research, and other pertinent information. As such,
this EIP assembles, organizes, and summarizes the
current knowledge on air treatment technologies that
are available for removing volatile organic
compounds (VOCs) from indoor air. VOCs are one
group of chemicals that can easily become gases, or
chemical vapors, which can migrate through soil and
enter buildings. Well-known examples of VOCs are
petroleum products (e.g., gasoline or diesel fuel), dry
cleaning solvents (e.g., perchloroethylene, aka perc)
and industrial degreasers (e.g., trichloroethylene,
TCE). This EIP does not represent EPA policy or
guidance.
1. PURPOSE AND SUMMARY
This EIP summarizes the state of the science on
selecting and using indoor treatment technology for
VOCs, also known as air treatment units (ATUs).
When selected and operated correctly, ATUs remove
VOCs from indoor air to keep their concentrations
below specified limits. This paper describes the

TABLE OF CONTENTS

1. PURPOSE AND SUMMARY
1
2. INTRODUCTION
2
3. AIR TREATMENT SYSTEM BASICS
3
3.1
Classes of Commercially Available


Treatment Units
3
3.2
Adsorption Principles and Performance
3
3.3
Photocatalytic Oxidation
7
3.4
Other Air Treatment Unit Types
8
3.5
Multiple Technology Air Treatment Units
9
3.6
System Sizes and Geometries
9
4. PERFORMANCE DATA AND

SPECIFICATIONS
10
4.1
Laboratory and Chamber Tests for


Efficiency and Capacity
11
4.2
Controlled (Unoccupied) Building-scale


Demonstrations of Air Treatment Units
14
4.3
Practical (Occupied) Field Applications to

VI Cases
16
5. SELECTING AN AIR TREATMENT UNIT,

DESIGNING AND IMPLEMENTING AN AIR
TREATMENT UNIT APPLICATION
21
5.1
Chemical and Physical Characteristics of

the Air Stream to be Treated
21
5.2
Building Characteristics
25
5.3
Design Process—Standalone Units
27
5.4
Design Process—Differences for Duct-


Mounted Systems
32
5.5
Air Treatment Unit Deployment
33
5.6
Communication and Instructions for


Occupants During Air Treatment Unit


Deployment and Operation
36
6. MONITORING AND VERIFYING AIR

TREATMENT UNIT PERFORMANCE
36
7. CURRENT CHALLENGES, LIMITATIONS,

AND RESEARCH AND DEVELOPMENT

NEEDS
37
7.1
Technology Development and Chamber


Verification Needs
38
7.2
Field-Scale Testing, Verification, and


Tech Transfer Recommendations
39
8. REFERENCES
40
ATTACHMENT A.

AVAILABLE VOC AIR CLEANER

EQUIPMENT
45
ATTACHMENT B.

AIR CLEANER EQUIPMENT 101

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ACRONYMS AND ABBREVIATIONS
ACH air exchanges per hour
ATU	air treatment unit
AHAM Association of Home Appliance
Manufacturers
AIC	acid-impregnated carbon
AS	air sparging
ASHRAE American Society of Heating,
Refrigerating and Air-Conditioning
Engineers
BIC	base-impregnated carbon
CADR Clean Air Delivery Rate (from AHAM
room air cleaner test)
CARB California Air Resource Board
CERCLA Comprehensive Environmental
Response, Compensation, and Liability
Act
CFM cubic feet per minute
DQO data quality objective
EIP	Engineering Issue Paper
EPA	U.S. Environmental Protection Agency
GAC granular activated carbon
HEPA high-efficiency particle air filter
HVAC heating, ventilation, and air
conditioning
IH	imminent hazard
ISO	International Standards Organization
MEK methyl ethyl ketone
NIST National Institute of Standards and
Technology
PCE	perchloroethylene, tetrachloroethylene,
or tetrachloroethene, also PERC
PCO photocatalytic oxidation
PPB	parts per billion
PPIA potassium permanganate impregnated
alumina
PPM parts per million
RH	relative humidity
RCRA Resource Conservation and Recovery
Act
SSD	subslab depressurization
SVE	soil vapor extraction
TCE	trichloroethylene ortrichloroethene
TCLP EPA's Toxicity Characteristic Leachate
Procedure
UV	ultraviolet light
VI	vapor intrusion
VOC volatile organic compound
different types of commercially available VOC ATUs,
how they work, and what factors influence their
effectiveness. This EIP also provides information on
how to select, install, operate, and monitor VOC
ATUs to meet indoor air quality objectives.
2. INTRODUCTION
The focus of this EIP is Comprehensive
Environmental Response, Compensation, and
Liability Act (CERCLA), known also as Superfund,
and Resource Conservation and Recovery Act
(RCRA) sites with VOCs in indoor air as the
contaminants of concern. The ATU technologies
described in this EIP can be applied when indoor air
VOC concentrations exceed specified limits, including
sites where VOCs are entering a building from a
subsurface source, commonly known as vapor
intrusion (VI). The technology can also be applied
when the VOCs are entering the building from
groundwater, for example in sumps.
One of the more common applications of VOC
ATUs is when a temporary reduction of indoor air
VOC concentrations is needed while a longer-term
solution is put in place. One example of this situation
would be using an ATU while a subslab
depressurization mitigation system is installed at a VI
site (and ultimately soil and groundwater remediation
is implemented to eliminate the need for indoor air
mitigation). In these cases, portable ATUs can be
deployed for weeks or months while the longer-term
solution is designed, permitted, and constructed.
Similarly, VOC ATUs can be used to reduce indoor
air VOC concentrations while possible sources of the
VOCs of concern are investigated.
This EIP surveys the available literature to address
five aspects of VOC ATU use: (1) What research has
been conducted on VOC ATUs that demonstrate
their effectiveness in removing chlorinated VOCs
from indoor air? (2) What VOC ATUs are
commercially available, how do they work, and what
are the recommended protocols, performance goals,
and monitoring for their use? (3) Based on available
2
Adsorption-based Treatment Systems

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test results, how effective are commercially available
VOC ATU technologies at removing or destroying
chlorinated VOCs from indoor air? (4) What are the
building- and unit (device)-specific factors that
influence VOC ATU performance? and (5) How
should VOC ATUs be selected, installed, and
maintained in a particular building? The paper also
identifies knowledge gaps that interfere with the
ability to answer these questions and recommends
research needs to fill these gaps.
3. AIR TREATMENT SYSTEM BASICS
3.1 Classes of Commercially A vallable
Treatment Units
ATUs for removing gas phase contaminants from
indoor air use many different technologies and come
in designs intended for standalone operation (as
portable, wall-mounted, or ceiling-mounted units) or
for installation in heating, ventilation, and air
conditioning (HVAC) ducts. The most common
VOC air cleaning technology in either design employs
a sorbent bed, or sorbent layer, usually composed of
carbon, to remove gas phase contaminants from the
air. Reactive ATUs, which use various chemical
reactions to change or breakdown the contaminants
into other compounds, are also commercially
available.
For the removal of the VOCs that are important for
VI (i.e., chlorinated compounds like trichloroethylene
and perchloroethylene), the most-demonstrated
technology at this time—and the primary focus of
this document—is carbon sorption, preferably with a
large amount of carbon relative to the air flowrate
needed. The principles and performance of other
commercially available technologies (e.g.,
photocatalytic oxidation) that may be proposed for
VOC control will also be briefly discussed.
Standalone devices use fans to pull room air into the
unit, through a sorbent bed, and back into the same
room after the air is "cleaned." Portable versions of
standalone devices are plugged into wall outlets and
can be easily moved. Wall- and ceiling-mounted units
that can be hard wired for power are also available.
HVAC ATUs, also called in-duct systems, are
normally installed in existing HVAC ducts or outside
the duct system but connect to it. The air from the
contaminated room enters the HVAC duct, possibly
after passing through other rooms on the way to the
return air duct inlet, and is decontaminated by the in-
duct ATU before being redistributed throughout the
building. In-duct devices often do not require a
dedicated power supply because the HVAC fan forces
the air through the device.
Each class of ATU has its advantages and
disadvantages, so it is important to understand your
situation, contaminants, humidity variability and
range, temperature, airflow needs, and other related
factors before choosing an ATU. Many devices are
sold without full unit test data and some are sold
without any test data. The lack of test data requires
the user to understand the principles of operation to
evaluate how well the technology, in the configuration
being sold, is likely to function for their needs.
Without test data, the person selecting the ATU and
designing its installation must be knowledgeable of
indoor air quality assessment and maintenance. A
professional engineer can assist in assessing unit
selection.
3.2 Adsorption Principles and Performance
3.2.1 Adsorption Principles
Two types of adsorption occur in ATUs:
physisorption and chemisorption. In physisorption,
compounds collect on the sorbent surface due to van
der Waals forces and other relatively weak binding
forces, and remain there until they are desorbed. Both
the sorbed compound and the sorbing surface remain
the same—no irreversible chemical changes occur.
Physi sorption systems can have single use or
regenerable sorb en ts. De sorption (i.e., release of the
chemical) can be intentional in a regeneration process
or may occur because of significant changes in
conditions (such as temperature, humidity, or
Adsorption-based Treatment Systems
3

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chemicals adsorbed) that prevailed after the original
adsorption. In chemisorption, the adsorbed
compound collects on the surface but reacts with the
surface irreversibly so that desorption is not possible.
This permanently removes the contaminant from the
airstream but also consumes the surface of the
sorbent (American Society of Heating, Refrigerating
and Air-Conditioning Engineers [ASHRAE], 1994).
Sorption occurs at a molecular level when VOC
molecules contact the sorbent surface due to
Brownian (or random) motion, as energetic molecules
move from a higher concentration in the air near the
sorbents to the relatively low concentration air in the
boundary layer at the surface of the sorbent (Figure
1). Advective currents (i.e., airflow), whether natural
or fan induced, bring contaminants into range where
this Brownian motion can become important.
Effective sorbents tend to have large surface areas
due to the presence of micropores. According to
ASHRAE (1994), "one gram of 1.5 mm diameter
carbon spheres would have an external surface area of
about 0.01 m2, which is only a small fraction of the
total adsorption surface of 1,000 to 1,500 m2/g."
Adsorbent Granule
Micropore
Contaminant
—— In Air
Figure 1. Diagram illustrating sorption of VOCs by solid, porous
sorbent granules
The most common sorbent in use for air cleaning is
granular activated carbon (GAC). For VOCs,
including the chlorinated hydrocarbons most
frequently encountered at VI sites, carbon acts as a
physisorbent. When the concentration of a
compound in the air goes down, the sorbed
contaminant may desorb due to the concentration
gradient driving force.
4
Carbon sorbents are usually placed in beds, or layers,
where small granules of carbon are held in place in a
confined space with mesh to allow airflow and
contact with the sorbent surface. Within these beds,
the sorbents are often described by their particle size.
The particle size is often expressed in "mesh" units
that refer to the sieves that pass or retain a given
particle size. For example, in 8x30 mesh GAC, at
least 96% of the granules by weight are larger than 30
mesh (0.60 mm) and at least 85% of the granules by
weight are smaller than 8 mesh (2.36 mm). Other
GAC sizes include 12x40 US mesh (0.42 to 1.70 mm)
and 6x16 US mesh (1.18 to 3.35 mm).
For a deep enough bed of carbon with a constant
VOC input, the downstream concentrations, or
breakthrough, has a standard-shaped curve starting at
0% penetration, or entry into the macro- and micro-
pores in the sorbent material (Figure 1), and rising to
100% if exposed long enough. Figure 2 shows the
typical slow initial breakthrough, followed by an
increasing rate, then an asymptotic approach to equal
the upstream concentration. Adsorption is followed
by desorption when the inflow of the contaminant is
eliminated while air is still flowing. Performance
measures include efficiency at a specific time, capacity
(how much VOC mass is removed) at a specific point,
and breakthrough time (how long it takes to reach,
for example, 50% of the upstream concentration
marked in Figure 2).
1.0

Contaminant


	Off

| 0.8
/\

CO
Efficiency = 1 - Penetration / \

§ 0.6
/ \

a.
/ \


<	-/ \

I 0.4
/ 5 \
/!8 \

T>
co


£ 0.2
/ 1 S1^ \
/ 1 CD \


1 gs

0.0
^ x—

0 50 100 150 200 250

Run Duration, h
Figure 2. Typical sorbent breakthrough curve for carbon or other
solid sorbents
Adsorption-based Treatment Systems

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3.2.2 Influences on Adsorption Performance
The efficiency and capacity of an adsorbent, such as
activated carbon, can be influenced by several factors
including:
•	Structure/nature of the target VOC(s)
•	Humidity and temperature
•	Concentration of the target VOC(s)
•	Concentrations of nontarget VOCs and other
gases
•	Properties of the carbon, such as the material
used to manufacture it and the grain (mesh)
size.
Different compounds adhere to carbon differently
(due to their polarity, van der Walls forces, etc.). More
strongly sorbing compounds can compete with and
cause more weakly sorbing compounds to desorb
from the active sites on the carbon where they are
bound. For example, incoming toluene will cause the
displacement of isobutanol as the toluene occupies
the sorption site (VanOsdell et al., 1996). This is
important if the total capacity of the bed is
insufficient to hold the more weakly sorbing
compounds and the weakly sorbing compounds are
of concern. In general, compounds with higher
molecular weights sorb better. For activated carbons,
moderately adsorb able gases tend to be those with
boiling points from -100° to 0°C, lighter gases tend
not to adsorb as well, and gases with high molecular
weights and boiling points adsorb preferentially
(Godish, 1989; Shepherd, 2001). Shepherd (2001)
provides relative carbon sorption strengths for
various VOCs. Table 1 shows the relative sorption
strength, molecular weights, and boiling points for
some selected compounds.
For example, Guo et al. (2006) ran sorption
performance and desorption experiments (using the
methodology of the ASHRAE Standard 145.1-2008)
on commercially available activated carbon media for
hexane, decane, toluene, PCE, 2-butanone,
isobutanol, and D-limonene. VOC concentrations
were in the range of 30—100 parts per million (ppm).
All the sorbents tested were different types of
Adsorption-based Treatment Systems
Table 1. Relative VOC Adsorption Rates by Molecular Weight and
Boiling Points (Shepherd, 2001)
Relative
Sorption
Strength
Compound
Molecular
Weight
Boiling
Point (C)
Strong
NITROBENZENE
123
211


TETRACHLORO ETHANE
166
147
TETRACHLOROETHYLENE (PCE)
165
121
STYRENE
104
145
XYLENE
106
138
NAPATHYLENE
128
217
TOLUENE
92
111
BENZENE
78
80
METHYL TERT-BUTYL ETHER
(MTBE)
88
55
HEXANE
86
68
ETHYL ACRYLATE
100
57
DICHLOROETHANE
99
99
METHYL ETHYL KETONE(MEK)
72
80
METHYLENE CHLORIDE
84
40
ACRYLONITRILE
53
74
ACETONE
58
56
VINYL CHLORIDE
62
-14
CHLOROETHANE
64
-12
BR0M0TRIFLU0R0M ETHANE
149
-58
Weak
METHANE
16
-161
activated carbon except one carbon/potassium
permanganate impregnated alumina (PPIA) blend.
Reporting performance as breakthrough time at 50%
removal efficiency for a 43-ppm average upstream
PCE test, Guo et al. (2006) observed values from 13
to 21 hours across five carbon sorbents showing that
the type of carbon can make a substantial difference
in performance and that it can be difficult to predict
performance beforehand. Both the sorbent with the
21-hour breakthrough time and the sorbent with the
13-hour breakthrough time were bituminous coal-
based granular carbons. PCE was in the middle in
terms of capture with 2-butanone, toluene, and

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isobutanol coming through quicker; n-hexane, about
the same; n-decane, slower; and d-limonene, much
slower. These data suggest that the presence of
common longer-chain alkanes, such as n-decane, and
naturally occurring terpenes, such as d-limonene,
could cause PCE to desorb from carbon beds.
In addition, water vapor is normally present in the
atmosphere at much higher levels than VOC
contaminants, with water vapor comprising up to 4%
of the atmosphere by volume and most organic
contaminants a few parts per million or less (U.S.
EPA, 2011a). Water vapor competes for sorption
sites on carbon. Higher humidity, thus, may result in
less sorption (Owen, 1996) and increasing humidity
can drive off sorbed contaminants. The influence of
humidity can vary by type of contaminant,
concentration, and type of carbon (Hines et al., 1990;
McDermott and Arnell, 1954; Moyer, 1983; Nelson et
al., 1976; Stampfer, 1982; Werner, 1985). The
efficiency of benzene sorption, as described by Deitz
(1988), steadily decreased as humidity increased. For
high concentrations (1,300 and 300 mg/m3 [240 to 56
ppm]), Werner (1985) reported that increased relative
humidity decreased carbon adsorption of TCE
significantly for lower TCE concentration tests with
decreasing influence as the TCE concentration
increased.
Data reported for chlorinated and other
hydrocarbons show some evidence of competition
between VOCs for active sorption sites. This
competition can manifest as a difference in
performance between a test of a VOC by itself and
that same VOC in a mixture. If two compounds A
and B are in a mixture, the strength of their binding
to carbon when mixed is not always well predicted by
single pure compound tests. VanOsdell et al. (1996)
investigated test methods for sorbents and sorbent-
based ATUs for removal of VOCs and the acid gases:
ozone, SO2, and NO2. Gas-phase challenges were
single compounds and mixtures. This study clearly
showed that gases penetrate sorbents at different rates
depending on the challenge mixture and the gas
concentrations. PCE was tested as a single gas and as
6
part of a specific test mixture as the representative
chlorinated hydrocarbon. One result showed that the
10% breakthrough time versus contaminant
concentration curves for PCE and other VOCs were
linear across approximately two orders of magnitude
of concentration with PCE breaking through more
slowly (sorbing better) than either toluene or 1-
butanol on the 4x8 mesh GAC. However, toluene
sorbed better than PCE (PCE came through more
quickly in mixture tests). For a five-VOC mixture,
total 1 ppm concentration test, of a full-scale 4x8
mesh GAC with a calculated 0.1 second residence
time (about 100 lbs. of GAC at 2,000 cubic feet per
minute [cfm]), both toluene and PCE reached only
10% over initial breakthrough in approximately 120
hours, showing that carbon has a substantial PCE
capacity. All VOCs were shown to desorb once the
challenges were turned off and the concentrations of
the VOCs in the influent air decreased. In these tests,
methyl ethyl ketone (MEK), 1-butanol, and hexane
came through more quickly than toluene or PCE. The
presence of acid gases common in urban atmospheres
(ozone, SO2, and NO2) also decreased the
breakthrough time for the VOCs. In addition to
shorter breakthrough times for VOCs, ozone has an
adverse, non-reversible effect on activated charcoal
performance as it attacks the pore structure of
activated carbon (Lee and Davidson, 1999).
Because sorption depends on the amount of surface
area of the sorbent, ATUs with more carbon are likely
to have higher efficiency and capacity. This is only a
general rule-of-thumb as carbons can vary by type,
pretreatment, and size of pellets/particles. ATU
geometry (e.g., accidental or designed bypass of the
sorbent bed) will also influence the efficacy of the
unit.
Chapter 46 of the ASHRA H Handbook—HVA.C
Applications includes information on contaminants,
problem assessment, reduction strategies, ventilation,
ATU system design, environmental influences, and
testing for ATUs for gaseous contaminants
(ASHRAE, 2015). Table 7 in ASHRAE (2015)
provides recommendations for the type of sorbent
Adsorption-based Treatment Systems

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media to use for different VOCs. Sorbents included
are GAC, PPIA, acid-impregnated carbon (AIC), and
base-impregnated carbon (BIC). GAC is the first
choice for dichlorobenzene, dichlorofluoromethane,
PCE, and 1,1,1 trichloroethane. PPIA is listed second
for TCE and as an alternate first for 1,1,1
trichloroethane. However, recent Qune and July 2016)
contacts with manufacturers by e-mail and at the June
2016 ASHRAE meeting gave only GAC as the
recommended sorbent for chlorinated hydrocarbons.
3.3 Photocatalytic Oxidation
Photocatalytic oxidation (PCO) refers to a type of
reactive ATU that uses light and catalysts to react
VOCs in the air into other species. Typically, these
devices are called UV-PCO for the ultraviolet light
used with photocatalytic oxidation. Specific devices
may be designed for different specific wavelengths
and this could influence performance. The usual
catalyst is titanium dioxide (TiC^).
PCO technology has been studied extensively at the
lab scale and to some extent at full scale (room sized
and up to units designed to treat a full building).
Although some studies show that—given enough air
passes (recirculation) through the devices—many
contaminants can be broken down to C02and water,
most studies show that intermediate oxidation
byproducts are formed, including aldehydes (such as
formaldehyde), acetone, and even phosgene. The
current commercial implementations of this
technology achieve multiple passes by discharge to
the room air where the byproducts may be breathed
in before re-entrainment to the device of some of the
room air (Hodgson et al., 2005; Jo and Park, 2004;
Mo et al., 2009).
In real-wo rid situations, it is impossible to know
ahead of time exactly what VOCs and other gases will
be present in the indoor air to be treated. Reactions in
the PCO devices may result from compounds in the
air other than the targeted VI compounds. VOCs like
chlorinated solvents, benzene, and other petroleum
hydrocarbons are always present in the indoor and
ambient atmosphere even in rural areas and remote
Adsorption-based Treatment Systems
sites (Kesselmeier and Staudt, 1999; Weisel et al.,
2008). Thus, it is nearly impossible to predict which
intermediaries will be formed without sampling and
analyzing the indoor air. Because intermediate
products become part of the breathing air in the
room or building being treated, and may have low
indoor-air screening levels, they must be considered
potentially as dangerous or more dangerous than the
original contaminants of concern (Alberici et al.,
1998; Hodgson et al., 2005, 2007; ICropp, 2014). In
short, there have not been enough field
demonstrations in complex real indoor atmospheres
to fully evaluate whether any observed destruction of
target VOCs outweighs the formation of undesirable
reaction byproducts by PCO devices.
Some PCO devices are ineffective or produce
excessive ozone. California maintains lists of ATUs
that are "potentially hazardous" because of ozone
generation along with the devices that they certify.
Kropp (2014) studied on-the-market PCO devices in
a small (580 L) chamber. Of the five devices studied,
three did not appreciably reduce the concentration of
the target contaminant. The fourth removed
contaminants, but the sorbent bed it contained
performed similarly with the UV light function turned
off. The fifth device destroyed dichlorobenzene over
time and did not make phosgene. Byproducts formed
by these devices included acetone, acetaldehyde, and
formaldehyde.
A lab-scale study by Alberici et al. (1998) also showed
destruction of compounds and creation of
intermediate byproducts. They examined byproducts
of UV-PCO (Ti02/UV) degradation of TCE, PCE,
chloroform, and dichloromethane at various humidity
levels. Among the byproducts they detected were
phosgene for TCE, PCE, and chloroform;
dichloroacetyl chloride for TCE; and trichloroacetyl
chloride for PCE. Chlorine gas (CI2) was also detected
as a final product. Alberici et al. (1998) also showed
that increasing the relative humidity (RH) from 20%
to 80% decreased the destruction from close to 100%
to 70% for a 30-minute exposure.

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Hodgson et al. (2005) generated extensive data on the
destruction of low concentration multicomponent
VOC mixtures by UV-PCO in a 20 m3 chamber.
Byproducts found included formaldehyde,
acetaldehyde, acetone, formic acid, and acetic acid.
These compounds were found at low levels, given
that the inlet concentrations were also low level. In a
study with a gas mixture intended to be similar to the
Hodgson et al. (2005) study, but done in an HVAC
test duct, RTI (2009) tested a different UV-PCO unit
and showed very small statistically significant
differences between upstream and downstream VOC
concentrations with some removal of several
compounds. In a follow-on study, Hodgson et al.
(2007) looked at chemisorbent scrubbers downstream
of the UVPCO device to reduce the production of
formaldehyde and acetaldehyde and found that the
combination "effectively counteracted the generation
of formaldehyde and acetaldehyde due to incomplete
oxidation of VOCs in the UVPCO reactor."
UV-PCO units are often not tested for efficacy or
byproduct formation, in part due to the lack of
standard test methods. Devices may be sold based on
lab-scale or similar device testing, or performance
expectations may simply be based on the presence of
the catalyst and UV light. Therefore, a UV-PCO
device should not be used for VI remediation in
occupied spaces unless test results are available that
demonstrate efficiency and the lack of toxic
byproduct formation for the conditions in the indoor
spaces being treated. Other reactive devices (such as
bipolar ionization and plasma-based units) have
essentially the same positives and negatives as the
UV-PCO units discussed above.
3.4 Other Air Treatm ent Unit Types
Other types of ATUs based on ozone generation,
chemisorption, or biofiltration are available for use
for indoor air VOC mitigation but further testing is
required because they are mechanistically unsuitable,
lack reliable performance data, or may have negative
1 https://www, arb.ca.gov/ research/ indoor/ o3g-list.htm
8
effects. They are presented in short form in this
section to cover devices that might be proposed or
considered for use at sites with VI applications. As
described below, these technologies have not been
adequately tested for VOCs nor for the applications
described in this document.
Although ozone generators may remove
contaminants by oxidation, they are concerns with
their use because of the dangers of ozone itself. As
stated in a previous EPA EIP (U.S. EPA, 2008):
"regulatory agencies have taken strong positions to
warn of potential problems with air cleaners
dependent on ozone generation.. .Methods that inject
ozone into the breathing space of the indoor
environment cannot be recommended as an air
cleaning technique, as ozone is a criteria pollutant.
The state of California has banned the sale of
residential ozone producing air cleaners effective in
2009." The California Air Resource Board (CAJRJB)
has a long list of devices under the heading
"Potentially Hazardous Ozone Generators Sold as Air
Purifiers."1 CARB also certifies other air cleaning
devices as being electrically safe and having low
ozone generation (CARB, 2016).2
Some ATUs are marketed as "ion generators." The
most common application of the ion generator
concept is particulate removal (Shaughnessy et al.,
1994), which is beyond the scope of this document.
Chemisorbent beds of permanganate, usually in the
form of PPIA, oxidize some airborne contaminants.
However, PPIA is not recommended for use with
chlorinated hydrocarbons, in part, because of
potential byproducts including hydrochloric acid
(Aguado et al., 2004; ASHRAE, 1994; VanOsdell et
al., 1996).
Biofiltration works by having plants or microbes
digest contaminants. These devices need to be
specifically planned for the specific compounds to be
removed from air, usually need stabilizing time for
2 https://www.arb.ca.gov/research/indoor/aircleaners/ce
rtified.htm
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microbes to self-select for ones that thrive on
particular contaminants, and may be slow working
(Guieysse et al., 2008). They have not been tested for
the applications discussed in this document.
3.5	Multiple Technology Air Treatment Units
Many commercially available ATUs include multiple
technologies and address both particulates and gases.
Frequently, a gas-phase device will add a particle filter
before and/or after a sorbent bed. Sorbent media may
also be affixed to fibers in combination gas-particle
filters. Multiple technology systems should be
evaluated based on an understanding of the effects of
their component parts. ATUs with particle filtration
before a carbon bed would be expected to behave for
VOCs as well or better as systems with carbon beds
alone, as the filters can prevent the carbon bed from
being fouled by particulate matter. Technologies that
use particle filtration ahead of UV-PCO would be
expected to be subject to most of the same
weaknesses as UV-PCO—only systems in VOC
removal applications because background VOCs
would be not be filtered out and could form reaction
byproducts in the UV-PCO unit. A unit with a
reaction chamber, such as UV-PCO, ahead of a
carbon bed is likely to be acceptable if there is
sufficient carbon or other sorbent(s) to adsorb the
reaction byproducts (e.g., formaldehyde, acetone,
acetic acid, and acetaldehyde).
3.6	System Sizes and Geometries
Air treatment units are available in a wide variety of
capacities and configurations. Treatment capacity is
typically rated as the airflow rate in cubic feet per
minute. However, units with similar airflow ratings
may differ in air treatment capacity due to different
treatment efficiencies resulting from such factors as
the type of sorbent material and air-sorbent contact
time within the units. At present, manufacturers do
not publish information on treatment efficiency using
a standardized method so comparisons are difficult.
For comparison within this EIP, treatment capacity is
assessed as airflow through the device.
Attachment A summarizes information about a wide
range of ATU equipment. The listed ATUs fall into
the following main categories: portable units and
built-in units intended for permanent or
semipermanent installation. Built-in units are
connected to existing HVAC duct work while
portable units are generally freestanding units that
withdraw air from the room, treat it, and discharge it
into the same room. Various systems are available
within each of these categories.
3.6.1	Sizing an Air Treatment Unit
The size of an ATU needs to be understood in the
context of the air exchange rate of the room, zone, or
building into which it is being installed. The air
exchange rate is the ratio of the airflow through the
building to the building volume, and is generally
expressed in units per hour, the number of air
exchanges per hour (ACH). EPA gives a 50th
percentile air exchange rate for residences of 0.45
ACH (U.S. EPA, 2011b). Commercial and
institutional buildings have design requirements for
air exchange that are expressed per person or per unit
area of building (International Code Council, 2009).
Those requirements typically result in air exchange
rates above four for many types of commercial and
institutional buildings (Engineering Toolbox, n.d.).
Larger buildings are typically divided into multiple
zones for heating or cooling, often defined as areas in
which temperature can be separately controlled often
by a single thermostat (Grondzik and Furst, 2000).
Building mechanical system designers generally seek
to create a "well-mixed" condition within each zone
for thermal comfort, which also plays an important
role in determining the effectiveness of a localized
ATU device within the zone (Ho ward-Reed et al.,
2008a, b; Int-Hout, 2015).
3.6.2	Portable Air Treatment Units
Most of the portable units listed in Attachment A are
smaller types weighing less than 100 pounds. These
units run off 110-volt current and have wall plugs.
Airflows range from less than 100 cfm up to
Adsorption-based Treatment Systems
9

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approximately 600 cfm. Assuming a residential
example, with a normal air exchange rate of one
exchange per hour or less, a targeted treatment air
exchange rate through the ATU of four
exchanges/hour might be selected if significant
sub slab or indoor sources of VOCs are expected to
be present. Thus, in a 10-ft ceiling space up to 900 ft2,
a 600-cfm unit could be used (see Section 5.3 for
further information on these types of calculations).
When selecting air flows, attention should also be
paid to a comfortable air velocity through the room
(ASHRAE, 2009) as well as the need for complete
mixing within the zone if the entire zone is to be
treated by a portable unit. This estimate will differ
from the treatment area estimates provided by the
manufacturers, but currently there are no standard
methods by which manufacturers estimate and report
this information.
Some larger portable units are listed in Attachment A.
These wheel- or cart-mounted units also run off 110-
volt current and have wall plugs. The listed airflows
are up to 2,000 cfm. Using the assumption applied
above, a 2,000-cfm unit could treat up to 3,000 ft2 in a
single well-mixed zone with a normal air exchange
rate of one per hour or less. One of the larger
portable units is optionally ductable, allowing
placement of the unit outside of the space being
treated. Alternatively, a large space could be treated
with multiple smaller units.
3.6.3 Built-in Air (Ducted) Air Treatment Units
Many types of built-in units are commercially
available (Attachment B). These devices are intended
for placement outside the space being treated, for
example in a drop-ceiling space or utility room, and
connected to an HVAC duct system or separately
ducted for outdoor discharge. The units with separate
ducts are hard-wired into the building's electrical
system and run off 110- or 220-volt current
depending on the model. Airflows range from less
than 100 cfm up to 10,000 cfm. HVAC-mounted
units are approximately the cross section of the
ductwork and 1—12 inches in depth. The airflow will
10
depend on the fan in the HVAC system and, thus, no
separate power source is required.
4. PERFORMANCE DATA AND
SPECIFICATIONS
Information that a user should consider for ATU
design includes airflow (for portable units), pressure
drop (for duct-mounted units), VOC removal
efficiency, sorbent capacity/lifetime, reliability and
uptime, noise levels, power usage, physical
dimensions, and weight. Many of these details are
cited on sales Websites and on the product's
packaging. Care is needed in interpreting data that
may not have been measured in the same way.
Available specification data for the reviewed devices
are summarized in Attachments A and B. Key testing
criteria include:
Total Airflow: For portable and many wall-mounted
devices, total air flow is the volumetric flow rate (In
cubic feet per minute) at which air is pulled from,
treated, and returned to the room. For duct-
connected devices with their own fan, this is the
volumetric flow rate at which air is treated. For
HVAC-mounted devices that do not have their own
fan, the airflow is usually determined at the air
handler of the HVAC system that the device is
installed in. Total airflow information should be
available for any portable device in any standard
catalog listing, from the packaging, and from
distributors. Important considerations for the user
include being sure that the flow configuration of a
device fits the needs of the project and that device
inlets and outlets are not obstructed.
Clean Air Delivery Rate (CADRV For portable
devices, CADR is the amount of 100% clean air that
is delivered by an ATU when tested using the
Association of Home Appliance Manufacturers
(AHAM, 2015) test method for specific types of
particles. An ATU with an airflow of 100 cfm and an
efficiency of 50% would have a CADR of 50 cfm.
The particulate CADR does not indicate whether a
unit can clean VOCs from the air. However, unit
Adsorption-based Treatment Systems

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testing for VOC removal can provide a VOC
CADR-like value based on similar measurements
and calculations.
Pressure Drop (or Resistance): For HVAC-
mounted devices, this is a measure of how difficult it
is to push or pull air through the device. A higher-
pressure drop may reduce airflow and increase energy
costs. Pressure drop is usually reported in inches of
water (in. H2O) in the United States. HVAC devices
intended for commercial buildings will have rated
airflow and pressure drop. These are usually on the
product label and will be available from the
distributor or manufacturer.
Removal Efficiency: Removal efficiency is the
percentage of a contaminant that is removed by the
device (outlet -j- inlet x 100). Removal efficiency may
change over time, with temperature and humidity
changes, and for different concentrations of VOCs in
the inlet air. Penetration is the inverse of efficiency:
efficiency = 100% x (1 — penetration). Removal
efficiency across the unit is not the same as the
achieved change in concentration in the indoor
environment in which the unit is operating.
Capacity: The mass of a compound that a device can
remove under specific conditions.
Reliability and Uptime: A typical metric of
reliability is the mean time between failures (My re felt,
2004) or availability as a percentage as uptime divided
by total time (Murphy and Morgan, 2006).
Noise Level: How loud a device will be, usually
reported for the highest airflow setting in decibels.
Power Usage: How much power the device requires,
often measured in watts or kilowatt hours. Some
devices report this as likely annual usage.
Dimensions: How wide, deep, and tall a device is.
Weight: For portable units, this could be the unit
without the filters, with filter weight reported
separately.
4.1 Laboratory and Chamber Tests for
Efficiency and Capacity
Standardized laboratory test methods for ATUs fall
into two main categories: HVAC/in-duct and room.
ASHRAE 145.2-2011 laboratory Test Method for
Assessing the Performance of Gas-Phase Air-Cleaning
Systems: Air-Cleaning Devices (ASHRAE, 2011) specifies
how to test HVAC/in-duct sorbent devices. Each test
uses a single contaminant in otherwise clean air as the
challenge. The initial efficiency, 1-hour, low
concentration, section is followed by the 4-hr, high
concentration, capacity test. After the challenge gas is
turned off, potential desorption is monitored for up
to 30 minutes. This test is performed at one
temperature/RH combination. This test allows
comparison of ATUs under controlled conditions for
pressure drop (resistance), clean filter efficiency,
capacity, and presence of de sorption (ASHRAE,
2011). This test has recommended compounds for
many chemical categories. ASHRAE 145.2 does not
have a suggested gas mixture test, and it does not
require testing for reaction products. Standing
Standard Project Committee 145, the committee
responsible for ASHRAE 145.2, is currently
considering changes to add reactive devices and
reaction product analysis. However, this is likely to
take years to incorporate and get approved as a new
version of the method. International Standards
Organization (ISO) 10121 is a similar test to the
current ASHRAE 145.2 with somewhat different
concentration levels suggested (ISO, 2014). These
tests are performed at the manufacturer's stated
airflow, so the airflow for a given pressure drop is
reported. In addition, a description of the device,
including dimensions, is required.
For portable and wall- or ceiling-mounted room
ATUs, the U.S. standard for particle removal is
usually the AHAM standard (AHAM, 2015). A room
unit is placed in a closed chamber with no airflow
through the chamber. The change in concentration
(the decay rate) is determined with the device on and
off (as a control). Comparison of these values and
Adsorption-based Treatment Systems
11

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accounting for the size of the room, leads to a CADR
as the output.
The methodology used in this test can be used to test
gas-phase filters if a gaseous contaminant and
analyzer are substituted in place of the particles and
particle analyzer. The National Research Council
Canada: NRCC-54013 Method for Testing Portable Air
Cleaners (NRCC, 2011) and the Professional Standard
of the Republic of China: Test of Pollutant Cleaning
Performance of Air Cleaners (PRC, 2010) implement this
approach. Some of the specifics are different, but the
essence of on/off decay rate comparisons is the basis
for this method. Other than the inclusion of ozone
testing in the Chinese method, these methods do not
call for testing reaction byproducts. However, it is
simple to add analysis for expected reaction
byproducts (although it may be difficult to predict
which compounds to look for). As an example of this
approach to testing, Chen et al. (2005) used this
approach in addition to single-pass efficiency
reporting. Output from tests of these types can be
used in modeling, as discussed later in this document,
either as the amount of clean air entering the room or
by separating the information into a device airflow
amount and a removal efficiency. Note that the clean
air rate and the efficiency will change over time in
long-term operations even if this is not observed in a
short-term laboratory test.
Filter/technology combinations from room ATUs
may also be tested for single-pass efficiency in a test
duct. This can be done by removing the
filter/technology from the housing and fan assembly
or by installing the whole device in a duct and
matching the duct airflow to the device's airflow rate.
This would be a non-standard use of a test method,
but can give useful data on the device. Some devices
can use different filters, so it is a good idea to be sure
that any test or in situ data that are reported are based
on the filters that will be installed.
In a laboratory study of five on-the-market gas-phase
ATUs, Owen et al. (2014a and b) ran ASHRAE
Method 145.2 tests on HVAC ATUs with sorbent
amounts ranging from under an ounce to 48 pounds.
Table 2 gives descriptions of the devices. These
ATUs were chosen with the expectation that they
would show a variety of results from low to high
removal efficiency across different test VOCs. The
VOC challenge gases in this study (toluene, hexane,
and formaldehyde) were tested separately as required
by the method. Also as required by the test method,
the initial efficiency portion of the tests was
performed at a gas concentration of 400 parts per
billion (ppb) for 1 hour. The capacity portion of the
test has the challenge level at 50 ppm for toluene and
25 ppm for hexane and exposure for up to 4 hours.
Formaldehyde was tested for only the initial efficiency
portion at 100 ppb.
The test results show that the different ATUs have
significantly different performance when compared to
each other and for different compounds. For most
ATUs, the efficiency was stable over the initial
efficiency test period; however, the efficiency
dropped for some. The reported initial efficiency
percentage is the average over the hour of the test.
For the capacity test, the efficiency is reported at
intervals over the course of the test, which runs for 4
hours or to less than 5% efficiency, whichever comes
first. The capacity is the calculated amount of the
challenge gas that the ATU captures during this test;
it is not adjusted by any desorption seen after the
challenge gas is turned off.
Table 3 summarizes the gas phase data for all five
filters. The initial efficiencies are graphed in Figure 3.
To show how the efficiency can change with loading,
Figure 4 plots the toluene efficiency curves over the
capacity tests (ATU A did not remove toluene). Note
that the capacity tests were performed at a very high
concentration relative to normal room air and are
intended to rank the relative performance of the
equipment, not to measure how long a filter will
function in an actual installation (i.e., not to estimate
filter lifetime).
12
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Table 2. AirTreatment Units Tested by Owen et al. (2014a, b)
Air Treatment Unit
ID
A
B
C
D
E
Size, in.
20x 25x <1
20 x 25 x 1
24x24x4
24 X 24 X 12
24 X 24 X 12
Application
residential
residential
commercial
commercial
commercial
Airflow rate, cfm
1,024
1,024
2,000
2,000
2,000
Type of air treatment unit
flat panel
pleated panel
pleated panel
rigid v-cell
rigid cell, deep pleat
Media type
activated carbon
activated carbon
50/50 blend of
(impregnated)
activated carbon and
permanganate-
impregnated alumina
loose fill media blend
of activated carbon
and potassium
permanganate,
48 Ibs./air treatment
unit
activated carbon,
coconut shell, small
granule (20x50
mesh), impregnated
for removal of
formaldehyde.
-12.8 Ibs./air
treatment unit
Table 3. Summary of Gas-phase Data from Owen et al. (2014a, b)
Challenge Gas
Measured Value
Air Treatment Unit
A
B
C
D
E

Initial weight of filter (carbon plus housing), g
266
463
2,043
27,264
17,234

Pressure drop at rated airflow, in. H2O
0.18
0.27
0.48
0.39
0.35
Toluene
Initial efficiency, %
0
30
35
61
91
Capacity test, lowest efficiency, %
0
4
3
37
24
Capacity, g
4.4
47.3
56
773.8
417.2
Hexane
Initial efficiency, %
6
27
34
70
95
Capacity test, lowest efficiency, %
0
0
0
2
15
Capacity, g
2.1
17.0
13.3
285.6
406.7
Formaldehyde
Initial efficiency, %
2
3
35
41
NA
Air Cleaner
Air Cleaner
Time after challenge elevated to high
concentration, min
Toluene
Formaldehyde
Figure 3. Initial efficiency test averages for the indoor gases	Figure 4. Toluene capacity test efficiency curves (Owen et al.,
(Owen et al., 2014a, b)	2014a, b)
Adsorption-based Treatment Systems
I
13

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4.2 Controlled (Unoccupied) Building-scale
Demonstrations of Air Treatment Units
An extensive series of well-controlled, factorial
studies of ATU performance have been conducted by
the National Institute of Standards and Technology
(NISI) and reported by Howard-Reed et al. (2005,
2007, 2008a, 2008b) and Persily et al. (2003). There
are several features of these studies that make them
somewhat different from common ATU VI
applications:
•	The contaminant tested was decane
introduced at a constant controlled rate from
a permeation oven directly into the indoor
environment. Decane is very nonpolar and
should adsorb quite well to GAC.
•	The studied structure was apparently a
research structure not actually occupied by
residents, which would tend to limit the
number of indoor sources of VOCs.
However, ambient air VOCs would be
expected to be present.
•	The studied structure was a double-wide
manufactured home with an unusual
crawlspace—one divided vertically by an
"insulated plastic belly" which contained the
HVAC ductwork (Persily et al., 2003).
However, the house was otherwise fairly
typical for modern U.S. residential
construction, consisting of three bedrooms,
two bathrooms, a utility room, and a
continuous living/dining/kitchen/family
room.
•	The test durations were relatively short—
typically 1 to 3 days. The ATU devices tested
had modest masses of sorbent, such as a duct
ATU with 0.75 kg of activated carbon or a
portable ATU with 500 g of carbon,
potassium permanganate, and zeolite
(Howard-Reed et al., 2007, 2008b).
Nevertheless, important insights and findings were
generated from this series of tests that should be
applicable to residential-scale implementations of
ATUs for VI:
•	The 140 m2 structure (1,506 feet2) was
operated either as a single ventilation zone,
using the forced-air HVAC system to provide
recirculation, or as multiple zones by turning
off the HVAC system and closing bedroom
doors. This had a dramatic influence on
contaminant distribution in tests of a single
portable ATU:
° When the source and ATU were in the
same isolated bedroom, with the HVAC
off, concentrations in other rooms of the
house were "almost unaffected" by the
contaminant release and remained low
(Howard-Reed et al., 2007).
° When the source and ATU were in the
same bedroom with the door closed but
with air distributed throughout the house
by the HVAC, the ATU in the closed
bedroom had the most effect on the
bedroom concentration but also had some
beneficial effects on VOC concentrations
in other rooms.
° When the source and the ATU were in
different rooms, with the HVAC off, "the
tests showed limited ability of the portable
ATU.. .to remove decane from the entire
house" regardless of whether the doors
were open or closed (Howard-Reed et al.,
2007, 2008a).
•	The average "direct removal efficiency"
(outlet concentration divided by the inlet
concentration) for the portable ATU tested
was 54%. The duct-mounted device had an
average removal efficiency of 42%.
•	New media was used in each test. When the
HVAC system was operated to mix the air in
the 140 m2 structure, the reduction in VOC
concentration in the whole structure was
approximately the same (within 15% for the
portable systems) as would have been
14
Adsorption-based Treatment Systems

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mathematically predicted based on
measurements at the outlet of the ATU for
both the portable and duct-mounted systems
(Howard-Reed et al., 2007, 2008a). The
authors interpret this result to mean that "a
single zone was achieved in the test house and
that the ATU was operating without
significant short-circuiting" (Howard-Reed et
al., 2007). Thus, the mathematical approaches
that were used by Howard-Reed to predict
changes in indoor air concentrations based on
the single pass removal efficiency of the ATU
were validated.
•	Although the authors define ATU
effectiveness as "the fractional reduction in
pollutant concentration that results from
application of a control device" (Howard-
Reed et al., 2007), they do not report their
results in these practical units. However,
effectiveness can be estimated from the
figures presented. In test 48 with the portable
ATU in use, HVAC on, and the ATU in a
bedroom with the door closed, the decane
concentration was reduced from 0.86 to
0.31 mg/m3 in that bedroom, which would be
an effectiveness of 64%. A similar
effectiveness (58%) can be estimated from the
kitchen/family room dataset. These effects
were observed over approximately 1 day of
operation after the ATU was turned on. The
reported air exchange rate for that test was
0.21 per hour. The portable ATU flow rate
was 340 m3/hour and the volume of the
house was reported as 340 m3. Thus, the ATU
was operating at 4.8 times the natural air
exchange rate of the structure.
•	When the house was operated as multiple
zones, with the contaminant injected into a
different room/zone than the portable ATU,
ATU effectiveness dropped to between 14
and 23% of the optimal predicted benefit
(Howard-Reed et al., 2007).
Howard-Reed et al. (2008a) summarize their results
stating, "When a building does not have a uniform
concentration of contaminants, an in-duct ATU may
not be as effective at reducing the whole-building
mass. Likewise, a portable will also not be as effective
at removing total mass when operated in rooms
different from the contaminant source, but it can also
effectively exceed predicted performance when the
source and ATU are in the same room isolated from
the remainder of the house." One practical
conclusion of this study for VI sites is that it is
advantageous to locate an ATU in the lowest level of
a building, close to the presumed VOC entry points,
or both.
Howard-Reed et al. (2008b) tested a small (37 m2;
398 ft2) unfurnished single-room house with wood-
frame construction and an attic. Decane was directly
injected into indoor air from a permeation oven. The
in-duct system tested in this house contained 0.6 kg
of activated carbon, alumina, and potassium
permanganate in a filter housing. The portable ATU
contained 2.7 kg of charcoal, potassium
permanganate, and zeolite. The portable ATU
operated on its highest airflow setting and delivered
an average flow rate of 350 m3/hour (206 cfm) versus
a manufacturer reported air flow rate of 510 m3/hour
(300 cfm). The average direct measurement of ATU
efficiency based on inlet and outlet concentrations
was 38% for the duct-mounted unit and 43% for the
portable ATU. Efficiencies calculated based on
measurements in the center of the room and either
transient or steady state mass balance were somewhat
less. The effectiveness defined as "the fractional
reduction in pollutant concentration that results from
application of a control device" was always greater
than 80%. Both ATUs were used for repeated short-
term challenge tests (8 for the duct mounted unit and
16 for the portable unit) and showed decreasing
decane removal efficiency as the total mass of decane
treated increased (without changing the sorbent).
Adsorption-based Treatment Systems
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4.3 Practical (Occupied) Field Applications
to VI Cases
A review of publicly available literature was
completed for sites where ATUs have been used to
reduce indoor air VOC concentrations in occupied
buildings. The documents reviewed are listed in
Table 4. A full summary of the parameters of the
treated space (e.g., volume, potential indoor sources,
HVAC operational parameters) was not consistently
available. These case studies include ATU
deployments in commercial, industrial, and residential
buildings. In some cases, multiple buildings were
included in the deployments. In these cases, one or
two representative buildings are discussed below.
4.3.1 Naval Weapons Industrial Reserve Plant,
Beth page New York (TetraTech, 2010)
Site 1 of the Former Drum Marshalling Area was
impacted by historic releases of chlorinated solvents
to soil and groundwater. Site impacts were remediated
by an air sparging/soil vapor extraction (AS/SVE)
system between 1998 and 2002. Soil gas testing
conducted in 2008 indicated elevated concentrations
of VOCs along the eastern boundary of Site 1,
affecting the adjacent residential neighborhood. Soil
gas, indoor air, outdoor air, and sub slab soil vapor
samples were collected from January through April
2009 at 18 residences. As an interim measure, ATUs
were placed in homes. Following additional sampling,
sub slab depressurization (SSD) systems were installed
in a subset of the homes.
The available reports did not provide information on
the size of each of the residences, the flow rate of the
ATUs, or ATU run time. For this discussion, we
assume that the residences were constructed similarly
and that most contain basements. Available analytical
data included indoor air concentration prior to
installation of the ATUs, indoor air concentration
after ATU installation, sub slab soil vapor
concentrations, and indoor ATU post-SSD system
installation (where applicable). A summary of key
parameters is provided in Table 5.
In Homes 1, 4, 6, 7, 10, 12, 13, and 14, the ATUs
reduced indoor air concentrations of TCE to levels
below the New York State health screening levels
when initial concentrations were above the indoor air
screening levels (Table 5). Similar reductions in
indoor air concentrations for PCE (82—87%) and
1,1,1-trichloroethane (33—72%) were also found at the
site (see referenced report in Table 4 for full
information). However, the ATUs did not appear to
adequately reduce indoor air concentrations in Homes
2 and 3 and SSD systems were subsequently installed
at those locations. SSD systems were also installed in
Homes 4, 6, 13, and 14 as a precautionary measure.
Across all cases, an average TCE concentration
reduction of approximately 80% was observed in the
post-ATU installation samples.
Assuming that the ATUs were operating in similar
home volumes and at similar flow rates, there appears
to be a correlation between elevated sub slab and
indoor concentrations (i.e., orders of magnitude
above screening levels) and the ability of the ATU to
reduce concentrations and maintain acceptable indoor
air concentrations (refer to the basements of Homes 2
and 3). In the two cases with sub slab concentrations
greater than 10,000 jug/m3, although reductions in
indoor concentrations of 67—81% were achieved in
indoor air, those reductions were insufficient to reach
the New York State screening level. This is consistent
with the mathematical design approaches outlined in
Section 5.3.2, which show that the needed ATU
capacity/number of ATU devices required increases
sharply with increasing baseline sub slab and indoor
air concentrations.
A complete dataset was not available for review, and,
thus, the data are not conclusive. For example, the
run time for each system is not provided. Some
residences may not have operated specific units
during the entire time between samples. However, the
apparent correlation between sub slab soil vapor
concentration and ATU effectiveness should be given
further consideration as it is discussed based on the
theory in Section 5.
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Table 4. Field Applications of Activated Carbon VOC Air Treatment Units (ATUs) at VI Sites
Site
City, State
(Regulatory
Authority)
Buildings
with
ATUs
Duration
of ATU
Operation
Report Name
Report
Date
Report
Author
Report Link
Report Notes
Bethpage
Naval
Weapons
Industrial
Reserve
Plant
Bethpage, NY
(NYDOH)
2 residences
with granular
activated
carbon ATUs.
8 months
Final Quarterly Data
Summary Report for
Soil Vapor Intrusion
Monitoring (May-
11/1/2010
TetraTech
http://www.navfac.n
avv.mil/niris/MID AT
LANTIC/BETHPAG
E NWIRP/N90845
Addresses only one
residence (#3). Has a
description of
ATU/SSD history.

August 2010)
NWIRP Bethpage,
NY


001199.pdf


3 residences
with granular
activated
carbon ATUs
4 months
Supplemental Vapor
Intrusion
Assessment
Summary Report
#2, Former
Honeywell Gardena
Site, 1711-1735
West Artesia
Boulevard,
Gardena, CA
3/25/2016
CH2M
htto://www.envirosto
r.dtsc.ca.aov/reaulat
ors/deiiverable doc
uments/6357958734
/Gardena%20Marke
tplace Sudd Vl%20
Assessment ReDort
No%202 32516.Dd
f
Documents
concentrations before
installation of air
treatment units at 3
residential locations
Gardena
Marketplace
Gardena, CA
(CADTSC)

Second Quarter
2016 Vapor
Intrusion Monitoring
Event Report,
Honeywell Gardena
Site, West Artesia
Boulevard,
Gardena, California
7/29/2016
CH2M
Not yet Dosted. But
will appear here
httD://www.envirosto
rdtsc.ca.aov/Dublic/
Drofile reDort.asD?al
obal id=19360536
Documents
concentrations after
installation of air
treatment units at 3
residential locations


9 commercial
bldgs. with
granular
activated
carbon ATUs
2.5 years
First Quarter 2016
Vapor Intrusion
Monitoring Event
Report, Honeywell
Gardena Site, 1711-
1735 West Artesia
4/29/2016
CH2M
httD://www.envirosto
rdtsc.ca.aov/Dublic/
deliverable docume
nts/6771593987/Gar
dena%20MarketDlac
e 1Q16 VI Monitori
HVAC manipulation
and crack sealing was
also used for
mitigation



Boulevard Gardena
CA


na ReDort 4291 6.d
df

CRREL
Hanover, NH
(NH DES)
1 industrial
research
facility
not specified
The Value of an
Iterative Approach
to VI Evaluation and
Mitigation: Lessons
Learned at the
CRREL Facility in
Hanover, NH

Geosyntec

Not available online
(2016 conference
presentation)
Bruscoe
Belmont, CA
1 commercial
bldg. with
8 months
Vapor Intrusion
Summary Report,
Former Brusco
Property
10/31/2013
CH2M
httD://aeotracker.wat
erboards.ca.aov/esi/
uDloads/aeo reoort/
3363481044/T1000
0002681 .PDF
Pre-cleaner
investigation
Property
(SFRWQCB)
AirPura c600
ATU.
Completion Report-
Interim Remedial
Measure and SVE
Construction
10/10/2014
CH2M
httD //aeotracker.wat
erboards.ca.aov/esi/
UDloads/aeo reoort/
2903016567/T1000
0002681.PDF

(continued)
Adsorption-based Treatment Systems

-------
Table 4. Field Applications of Activated Carbon VOC Air Treatment Units (ATUs) at VI Sites (continued)
Site
City, State
(Regulatory
Authority)
Buildings
with
ATUs
Duration
of ATU
Operation
Report Name
Report
Date
Report
Author
Report Link
Report Notes
Early Ave.
Torrance, CA
(LARWQCB)
7 commercial
bldgs. With
AirPura C600
air purifiers.
2 years
First Quarter 2014
Supplemental Vapor
Intrusion Evaluation
Summary Report
4/30/2014
CH2M
http://aeotracker.wat
erboards.ca.aov/esi/
uploads/aeo reoort/
5185718595/SL204
1M1512.PDF
HVAC manipulation
and crack sealing was
also used for
mitigation
Interim Mitigation
Measures and
Indoor Air Quality
Assessment at Suite
K of Torrance
Business Center
Property
5/15/2014
CH2M
http://aeotracker.wat
erboards.ca.aov/esi/
uploads/aeo report/
4345945239/SL204
1M1512.PDF
HVAC manipulation
and crack sealing was
also used for
mitigation
Brighton
Brighton, MA
(Mass DEP)
unclear
unclear
Post Temporary
Solution Status and
Remedial Monitoring
Reports October
2014	through March
2015
7/1/2015
CH2M
http://public.dep.stat
e.ma.us/fileviewer/D
efau!t.aspx?formdat
aid=0&documentid=
309887

Omega
Chemical
Corporation
Superfund
Site
Whittier, CA
Total of 16 air
treatment
units in 2
commercial
buildings
17 months at
one location
Short Term
Mitigation Air
Sampling Report for
April 2012
Omega Chemical
Superfund Site
6/6/2012
CDM

Other actions in both
buildings included
HVAC adjustment
and crack sealing
Administrative
Settlement
Agreement and
Order on Consent
for Removal Action
10/2/2009
US EPA
Region IX
CERCLA
Docket
No. 09-
2010-02
https://vosemite.epa
aov/r9/sfund/r9sfdo
cw.nsf/3dc283e6c5d
6056f882574260074
17a2/6f77e358ecc1
51a288257a55007f2
b0b/$FILE/AOC%20
indoor%20air%20fin
al 110909.pdf
28th Street
Elementary
School
Los Angeles,
CA
10 class-
rooms
located in 7
bungalows
with granular
activated
carbon ATUs
About 7
years in
some
bungalows
Quarterly Indoor Air
Sampling and
Analysis Report 3rd
Quarter 2009
1/5/2010
Geosyntec
http://www.envirosto
rdtsc.ca.aov/public/
deliverable docume
nts/7116742789/28t
h% 20St% 203rd% 20
Qtr%20IA%20Repor
t-complete.pdf
Carbon filtration
installed after initial
HVAC modification
and crawlspace
ventilation was
partially successful.
Annual carbon
change out.
2015 Annual Indoor
Air Sampling/
Analysis Report
3/1/2016
Geosyntec
http://www.envirosto
rdtsc.ca.aov/oublic/
deliverable docume
nts/4021716058/28t
h%20St%202015 A
nnual IA%20Reoort
.pdf

18
I
Adsorption-based Treatment Systems

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Table 5. Summary of Bethpage Data'
Home
#
Subslab Soil
Vapor TCE
Concentration
(|ig/m3)
Indoor Air TCE
Concentration
Prior to Air
Treatment Unit
Installation
(|ig/m3)
Sample
Location
Indoor Air TCE
Concentration
Post- Air
Treatment Unit
Installation
(|ig/m3)
Percent
Reduction
Indoor Air TCE
Concentration
~4 Months
Post- Air
Treatment Unit
Installation
(|ig/m3)
SSD System
Installed Prior
to 4-Month
Event?
1
160
2.2
Living Space
0.44
80
0.93
N
2
16,000
100
Living Space
3.1
97
9.2
Y
16,000
140
Basement
46
67
61
Y
3
13,000
110
Living Space
2.8
97
16
Y
13,000
180
Basement
34
81
79
Y
4
1,400
6.1
Living Space
1.1
82
NS
Y
1,400
6.8
Basement
1.2
82
3
Y
6
740
6.6
Living Space
1.2
82
NS
Y
740
43
Basement
2.1
95
13
Y
7
170
0.40
Living Space
NS
NS
NS
N
170
0.75
Basement
0.2 J
73
0.4 J
N
10
300
ND
Living Space
NS
NS
NS
N
300
2.9
Basement
1.5
48
2.1
N
12
94
ND
Living Space
NS
NS
NS
N
94
0.55
Basement
0.21 J
62
0.22 J
N
13
230
ND
Living Space
NS
NS
NS
Y
230
1.5
Basement
0.50
67
1.9
Y
14
290
0.73
Living Space
NS
NS
NS
Y
290
1.9
Basement
ND
NS
NS
Y
1 Only select data shown; refer to the administrative record for the full data set.
Gray shading indicates exceedance of a New York State Department of Health Screening Level (5 |jg/m3 for indoor air and 250 [jg/m3
for subslab).
NS = Not Sampled; ND = Not Detected; J = estimated
4.3.2
Garden a Marketplace, Garden a, California
(CH2M 2014b, 2016a, 2016b)
This site is a commercial development consisting of a
grocery store and a strip mall over contaminated soil
and groundwater. ATUs were installed as an interim
VI mitigation measure to reduce indoor-air
concentrations of PCE and TCE. Information for
each affected space is as follows:
• Space Number 1
° Commercial strip mall space with
independent HVAC unit.
° Single story, approximately 1,700 ft2.
° Premitigation subslab concentrations:
PCE = 130,000 jig/m3; TCE = 4,600
(Ig/lTl3.
° Temporary mitigation measures included
(1)	HVAC adjustment to increase outdoor
air ventilation and change from
intermittent to continuous operation and
(2)	installation of one portable ATU with
a flow rate of approximately 500 cfm.
° Indoor PCE decreased from 4.9 jitg/m3 to
1.4 Jig/m3 (71% reduction). Indoor TCE
decreased from 0.36 jig/m3 to 0.11 |ig/m3
(69% reduction).
Adsorption-based Treatment Systems
19

-------
° Reductions sustained for at least 1 year
prior to startup of a SVE pilot test, which
further reduced indoor-air concentrations.
Final PCE and TCE concentrations prior
to SVE startup were 1.8 and 0.13 jitg/m3,
respectively with concentration ranges
varying from 1.1—1.8 jug/m3 and
nondetect—0.17 jug/m3, respectively.
• Space Number 2
° Commercial strip mall space with
independent HVAC unit.
° Single story, approximately 1,700 ft2.
° Premitigation sub slab concentrations:
PCE = 55,000 jug/m3; TCE = 2,700
(Ig/lTl3.
° Temporary mitigation measures included
(1)	HVAC adjustment to increase outdoor
air ventilation and change from
intermittent to continuous operation,
(2)	sealing of slab cracks and utility line
entry points through the slab, and
(3)	installation of two portable ATUs each
with a flow rate of approximately 500 cfm.
° Indoor PCE decreased from 87 jug/m3 to
0.73 jug/m3 (99% reduction). Indoor TCE
decreased from 7 jug/m3 to 0.079 jug/m3
(99% reduction).
° Reductions sustained for at least 1 year
prior to startup of a SVE pilot test, which
further reduced indoor-air concentrations.
Final PCE and TCE concentrations prior
to SVE startup were 0.25 jug/m3 and
0.083 jug/m3, respectively with
concentration ranges varying from 0.25—
1.2 jug/m3 and nondetect—0.15 jug/m3,
respectively.
3 http://www.newtonma.gov/gov/health n human servi
ces/enviro /environmental health information.asp
4.3.3	U. S. Army Corps of Engin eers, Cold
Regions Research and Engineering
Laboratory, Hanover, NH (Calicchio and
Malinowski, 2016; Clausen and Shoop,
2015; Foikes and Tripp, 2016)
This site is a large, multistory research building with
industrial operation overlies multiple soil and
groundwater VOC sources. ATUs were installed to
reduce indoor air concentrations of TCE.
Information for the site is as follows:
•	200 ATUs with an approximate maximum
flow rate of 300 cfm (per unit) were
distributed throughout the building.
•	Subslab concentrations: TCE = 12,000—
3,000,000 jug/m3.
•	Pre treatment indoor air concentrations: TCE
= 2—84 jug/m3.
•	No other concurrent mitigation measures
reported with treatment unit deployment.
•	Indoor air TCE was reduced 25—75%.
4.3.4	Nonantum West Street Area, Newton, MA
(Newton Environmental Health,3 2016; Mass
DEP,4 2016)
This site, a former auto-salvage parts facility, is
underlain by TCE contaminated groundwater. To
screen the area for the existence and elimination of
imminent hazard (IH) conditions, 39 groundwater
monitoring wells were installed and sampled; and 157
indoor air grab samples from 57 residences were
initially analyzed. For residences with TCE
concentrations above the IH limits, air
cleaning/purifying units were installed. Site
information and results were as follows:
•	ATUs contained 12.5 pounds of activated
carbon plus a layer of zeolite (for moisture
removal) and potassium iodide (KI) to
enhance chemisorption of certain organic
compounds.
•	Flow rate was 125 cfm (per unit).
4 http:/ /public.dep.state.ma.us/fileviewer/Default.aspxPfo
rm dataid=0 &do cum entid=368843
20
Adsorption-based Treatment Systems

-------
•	Indoor air concentrations of TCE were <1—
180 |_Lg/m3.
•	TCE concentrations were reduced by 50—75%
within 1 week of operation when initial TCE
concentrations were 60—120 jitg/m3.
•	TCE concentrations were reduced by 50—75%
within 2 weeks of operation when initial TCE
concentrations were 6—20 jig/m3.
4.3.5 Field Study Summary
Comparison of these field studies highlights some of
the challenges in using this type of information to
assess ATU performance:
•	It may not be possible to distinguish the effect
of VOC ATUs from other concurrent
measures such as sealing and HVAC
modifications. Because ATUs are generally
employed in situations perceived as urgent,
the natural inclination of the project team is to
implement multiple measures to best ensure
reductions in indoor air concentrations.
•	Building size (especially volume) and ATU
operating flow rate are not adequately
reported to allow calculating a normalized air
exchange rate through the ATUs. It is
possible that a more extensive information-
gathering effort could develop this
information for the sites in question.
•	Building-specific indoor/outdoor air
exchange rates through natural ventilation and
HVAC operation are not available. This
makes it more difficult to accurately estimate
the VOC mass flux into the building at a
specific time. However, data are sometimes
available on VOC mass accumulated in an
ATU carbon bed over a long operational
period, which could be used to estimate VOC
mass flux into the structure. Air exchange
rates could potentially be established through
field measurements as the implementations
are ongoing.
• Multiple ATUs may be needed to achieve
mitigation goals within given timeframes.
Without the normalized parameters mentioned above,
it is difficult to draw generalized conclusions about
ATU performance from the available case studies.
However, the case studies suggest that ATUs can be
part of a multimeasure effort to reduce indoor VOC
concentrations.
5. SELECTING AN AIR TREATMENT UNIT,
DESIGNING AND IMPLEMENTING AN AIR
TREATMENT UNIT APPLICATION
This section provides detailed information on
designing and implementing a successful ATU
installation for reducing indoor air VOC
concentrations in a variety of buildings, including
important factors for selecting an ATU and how to
design, install, and operate an ATU system.
5.1 Ch emical an d Physical Characters tics o f
the Air Stream to be Treated
Air in buildings, even within a single HVAC zone, is
not uniform. The contaminants of concern and
background VOCs can both vary in concentration
spatially and temporally. Humidity and temperature
also vary across time in the same room, by location in
a building, and across climate zones. Outdoor air
conditions can also affect VOC ATU performance
because outdoor air can influence indoor air VOC
concentrations.
5.1.1 Humidity
The relative humidity (RH) level is important in
choosing and maintaining an ATU because the
humidity can change the performance of some types
of ATUs (see Section 3). In general, indoor air in
controlled spaces is likely to be in the 30—65% RH
range in the breathing space. For GAC, higher
humidity (>80% RH) will reduce sorbent
effectiveness (ASHRAE, 2015).
Adsorption-based Treatment Systems
21

-------
While the effects of humidity will vary among GACs
and contaminants, Owen (1996) showed much better
VOC removal efficiency below 65% RH than above
80% RH for 4x8 mesh coconut shell carbon. Keener
and Zhou (1990) reported on the influence of
humidity for one type of pelletized carbon over a
range of 54—92% RH for toluene, carbon
tetrachloride, ethylbenzene, methylene chloride, and
ethyl alcohol at VOC concentrations of 300—900
ppm. They found a decrease by as much as 65% in
VOC capacity over this RH range with great
variability across the compounds. They also report a
decrease in toluene capacity of 75% when humidity
rises from 5% to 92% based, apparently, on calculated
values. However, because these concentrations are so
much higher than those found in indoor air, it is
difficult to know whether the relationship can be
easily extrapolated to low concentration VOCs.
For reactive ATUs such as photocatalytic systems, the
presence of humidity may change the reaction rate,
reaction products, or both depending on the specifics
of technology and the other contaminants in the air.
It may also change the reaction byproducts. Alberici
et al. (1998) showed that for TCE and the test
devices, increasing the RH from 20% to 80%
decreased the destruction from nearly 100% to 70%.
Similarly, Lee et al. (2016) saw a decrease in air
cleaning efficiency with increasing RH, ranging from
20% to 55% for benzene, toluene, and xylene. In
contrast, Jo and Park (2004) showed no variability in
VOC destruction due to RH. Mo et al. (2013) showed
water vapor has a significant effect not only on the
photocatalytic decomposition rate of toluene, but also
its byproducts due to the competitive adsorption
among water vapor, toluene, and its breakdown
byproducts. If photocatalytic devices are employed at
field scale, the designer should understand the device-
specific humidity effects that could apply.
5 https: / /www.epa.gov/indoor-air-quality-iaq/mdoor-
particulate-matter#indoor pm
In summary, increases in humidity are well-known to
drive sorbed contaminants off GAC. This effect is
seen most often at very high humidity (>80% RH)
and would result in the ATU temporarily emitting
more VOCs than are present in the inlet air. This
desorption, while highly undesirable for short-term
indoor air quality, actually allows the carbon to sorb
additional contaminants once the humidity is lower
again, which means that the ATU should return to
functionality after a temporary humidity increase.
However, for best use of carbon-based ATUs,
humidity control, at least to prevent surges of high
humidity, is useful. This control could take the form
of a separate dehumidifier or operation of an air
conditioning system.
5.1.2	Temperature
Most occupied buildings in the United States are
conditioned to keep the air temperature at
comfortable levels, usually in the low to mid 70s (°F).
However, some residences either do not have air
conditioning or allow the temperature to decrease
into the 50s or low 60s in the winter to reduce heating
costs. Temperatures in the summer can rise into the
90s or higher in unconditioned structures in some
parts of the United States. With lower temperatures,
RH increases, and vice versa for higher temperatures.
High temperatures, given a constant RH, will decrease
sorption capacity and efficiency (ASHRAE, 2015).
This decrease may be similar across carbon types and
devices such that relative ranking of sorbents or
ATUs may be the same.
5.1.3	Particles
Indoor air contains particles. The concentration and
sizes of the particles will depend on the sources in the
structure and the filtration system, if any, in use.
Sources of indoor particulates include ambient air
infiltration, cooking, combustion heating systems,
cigarette smoking, and some hobbies.5 While sorbent
22
I
Adsorption-based Treatment Systems

-------
beds will not catch many particles, those that are
caught can hinder the performance by blocking active
sorption sites or increasing pressure drop by
obstructing air flow. It is common to include a
particulate filter upstream of carbon bed type ATUs.
Some units, especially room units, come with
standard particle filters upstream of the carbon beds.
Sorbentbeds also shed particles with use, which can
constitute at least a nuisance. To avoid having these
particles emitted into the air, a particle filter may also
be used downstream of the sorbent bed. In either
case, the particle filters that are present in a VOC
ATU should be checked regularly and changed
according to the manufacturer's recommendations.
Air filters that include sorbents within or attached to
fibrous media are intended to provide particle
filtration and gas-phase filtration in one unit. Note
that when particles are captured and lead to a pressure
drop increase, the entire filter must be replaced.
However, for many existing buildings, this type of
filter will fit into the existing HVAC filter housing
and can provide a simple and quick-to-install
adaptation to including VOC filtration in an existing
building. If a sorbent-containing media is introduced,
it should continue to provide adequate particle
filtration (ASHRAE, 2009). The expected particle
loading on the filter based on the indoor air
particulate load would then be an additional control
on the frequency with which such a dual-purpose
filter would need to be replaced.
5.1.4 Target Organics
Target VOC compounds for VI situations are most
frequently chlorinated hydrocarbons, such as PCE
and TCE, that enter the residence or commercial
building in soil gas, primarily advectively (U.S. EPA,
2012). Thus, differential pressure across the building
envelope will strongly influence the mass flux into the
structure as the contaminants can enter with airflow.
The differential pressure across the building envelope
is in turn affected by the differential temperature
between the building interior and exterior as well as
wind loads (U.S. EPA, 2012). These factors influence
the air exchange rate of the structure (U.S. EPA,
2011b). These two effects can offset to some extent,
so the percentage increase in indoor concentration
due to increased entry rate can be lower than the
percentage increase in the mass flux.
However, even in the absence of a differential
pressure driving force, contaminants can enter
diffusively following concentration gradients (U.S.
EPA, 2012). Due to this method of entry, it is
possible that air treatment could increase the mass
flux of entry as the ATU lowers the indoor
concentration.
5.1.5 Nontarget Org an ics an d Other Air
Contaminants
As with the target organics, other organics (both
anthropogenic contaminants and naturally occurring
VOCs) will enter the building at variable mass flux
rates, dependent in general on whether the area
around the building is urban, suburban, or rural, as
well as how well the building is weatherized.
Inorganic constituents such as ozone, SO2, and NO2
that can also interact with sorbents are present in all
urban atmospheres. Differential pressure,
concentration gradients, and outdoor environmental
conditions will influence the rate of entry of these
contaminants into the building. Opening of windows,
mostly in homes, may result in increased air exchange
and allow outdoor contaminants to more easily enter
the building. Increasing outdoor inlet air to HVACs
(for example, when outdoor temperatures yield
heating/cooling energy savings) will cause outdoor air
pollutants to enter the building. Some outdoor
contaminants (e.g., ozone) will enter the building and
can react with other compounds including those that
enter through VI, potentially forming different
contaminants.
However, for many buildings, most indoor air organic
contamination comes from indoor sources. These
sources include off-gassing from furniture, carpets or
equipment, cooking, pesticides, paint, cosmetics,
Adsorption-based Treatment Systems
23

-------
personal care products, personal hygiene products,
smoking, air fresheners, and others. The nontarget
compounds compete for sorption sites and may
deactivate photocatalytic technologies (Hay et al.,
2010). The best method for lowering concentrations
of nontarget organics is source removal or reduction
(ASHRAE 2009; U.S. EPA 2011a, 2012). Reducing
these compounds will help any ATU function more
effectively. It is important to realize that an ATU will
treat the air, to the extent possible, for both the target
compounds and the nontarget compounds.
Depending on the sorption properties of the target
compounds and the nontarget compounds, the ATU
may take up the intended compounds better or worse
than the unintended compounds.
Although the authors were not able to find systematic
tabulated information about the relative strength of
carbon adsorption for various VOCs in indoor air
applications, the literature on gas phase carbon
efficiency for air pollution control devices could be a
useful alternative in evaluating interactions between
VOCs. Example sources of tabulated information
include U.S. EPA (1998) and Shephard (2001).
Sorption for a given compound will change
depending on the other compounds in the same
atmosphere. In a test of HVAC-insertable carbon
beds (a 24x24x24" housing filled with 100-pounds of
carbon in 1" deep trays in a zigzag format inserted
into the test rig's HVAC duct section), VanOsdell et
al. (1996) tested a five-VOC mixture (Figure 5). The
test concentrations were 0.2ppmperVOC fora total
of 1 ppm VOC. The efficiency curves in the figure are
shown as trend lines based on the observed data. The
graph shows differences among the compounds in
how well the carbon bed removed them from the air
(toluene is the most strongly sorbed, followed by
PCE). This test was run long enough that the less
well-sorbed compounds (isobutanol and MEK) were
pushed through the bed when the more strongly
sorbing compounds displaced them from active
sorption sites. This result can be shown since the
Efficiency Curves for 5-VOC Mixture Test
of HVAC Carbon Bed
100
From top
to bottom:
60
?	Toluene
140	\ -PCE
- Hexane
20	-- isoB
MEK
o
-20
0	50	100 150 200 250
Time (h)
Figure 5. Efficiency curves for a five-compound VOC test mixture
from VanOsdell et al. (1996)
Efficiency Curves for 5 VOC ~ 3 Acid Gas Mixture on
HVAC Carbon Bed
From top
to bottom
at end of
challenge:
ISOOUTAMX
Figu re 6. Efficiency curves for a five-compound VOC test mixture
with three additional inorganic gases from VanOsdell et al. (1996)
outlet concentrations were above the inlet
concentration (where efficiency is thus less than 0%)
after the 200-hour mark.
A separate test with the same five-VOC mixture,
same RH, and same airflow rate but with acid gases
(ozone, SO2, and NO2 at National Ambient Air
Quality Standard maximum levels) added to the
challenge gas mixture is shown in Figure 6 (also
reported in VanOsdell et al., 1996). This second test
was run for just over 100 hours.
Comparing Figures 5 and 6 shows that the presence
of the acid gases caused the VOC compounds to
break through the active charcoal bed much quicker
(VanOsdell et al., 1996). There is also less apparent
separation in efficiency between strongly and weakly
24
Adsorption-based Treatment Systems

-------
adsorbing VOCs. In the later stages of the test, all the
challenge gases were turned off, as shown by the red
line, such that only clean air passed through the
carbon bed. The efficiencies then had an increase due
to a calculation artifact in which the data were still
presented in this period, relative to the upstream
concentration during the challenge on portion. Thus,
the graph shows that all the challenge gases continued
to be present in the treated air after they were no
longer present in the influent, showing desorption.
PCE desorbed the least of the five VOCs.
5.2 Building Characteristics
Characteristics of the building requiring treatment
play a large roll in selection, deployment, and
monitoring of an ATU for a particular space. Some of
these characteristics include:
•	Occupancy
•	Size of the space requiring treatment
•	Operation of HVAC systems and the target
air exchange rate
•	Existing air circulation patterns
•	ATU power requirements
•	Security requirements
•	Space requirements.
Each of the listed characteristics influences the
necessary air exchange rate and is discussed further in
the following subsections. Determining these
characteristics will generally require a combination of:
•	Review of plans and building energy audits/
HVAC balancing reports
•	Discussions with building managers who have
knowledge of HVAC systems operation,
tenant activities, and other factors that can
affect indoor VOC levels
•	A field survey, using standard forms generally
found in VI guidance documents and is often
called an "Indoor Air Sampling
Questionnaire" or "Building Evaluation
Form."
5.2.1 Type of Occupancy
The use of the treated space should be considered
during selection and sizing of the ATU. Specific
considerations are as follows:
•	Target indoor air concentrations: Target
indoor air concentrations should be based on
the occupancy of the space (commercial vs.
residential) and specific exposure durations. If
very low target air concentrations are required,
a higher level of ATU efficiency will be
needed for the same level of contaminant
flux.
•	Products in use: Products in use within the
treated space can have significant impact on
recommended air exchange rates (fresh air
supply requirements) and carbon use in air
cleaning applications. For example, if the
space being treated has frequent use of
products that emit VOCs, the presence of
these VOCs, rather than target compound
concentrations may drive the rate of carbon
consumption and breakthrough times. Note
that these products include intentionally used
items such as deodorant and bug spray and
always-present items such as furniture and
carpet. Particular attention should be paid to
any situation where a liquid source of VOCs
may be in equilibrium with indoor air because
they can provide a large source as the ATU
removes VOCs from indoor air. Possible
examples of such sources include a loosely
covered jar of paint thinner, a gasoline can
with the air vent open, or air fresheners
designed to continuously emit a fragrance.
When a volatilizing substance is at equilibrium
with the overlying air, and the concentration
in the overlying air is reduced, the rate of
volatilization increases (Le Chatelier's
Principle; Oxtoby et al., 1990).
•	Noise tolerance: The noise tolerance of the
occupants should be considered when
selecting the specific ATU and number of
Adsorption-based Treatment Systems
25

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units required. Most ATUs are well tolerated
by occupants, with noise as the primary
complaint. In a residential or office setting,
units are often too noisy to be operated at the
highest level (Lawrence Berkley National
Laboratory, 2016). The background (ambient)
noise level of the space should be considered;
for example, bedrooms would typically have a
low acceptable noise level.
5.2.2	Size of Treated Space—Volume Requiring
Treatment and Space Needed for
Portable Unit
The volume of air to be treated within the target
space is a critical element for ATU selection. The
volume of the space is used—along with the
estimated number of air exchanges per hour—to
select the size, operating speed, and number of units
needed. This selection process requires an
understanding of not just square footage, but also
ceiling height and the degree of interconnectedness of
airflow between rooms and floors. As discussed in the
following sections, this will also require an
understanding of the zones in the building in which
air is mixed (either naturally through air currents or by
a forced air system).
Once the required volume of air treatment has been
determined, an evaluation is conducted to determine
the number of air cleaning units required. Residential
portable units are typically small (Attachment A) and
can often be placed in an unobtrusive location;
however, free flow of air in and out of the unit and
good mixing of the room air should be ensured. If a
larger treatment volume is needed, several units may
be required to meet the target air exchange rate and
multiple small units may become difficult to locate.
5.2.3	HVA C Systems an d Air Exchange Rate
Existing HVAC system operating parameters (e.g.,
flow rate, on-off cycling) and connectivity between
6 http: / /www.engineeringtoolbox.com/air-change-rate-
room-d 867.html
the treated space and the remainder of the building
need to be considered during ATU selection. HVAC
systems often recirculate some portion of the air
within the building as well as provide some fresh
outdoor air (Althouse et al., 1988). Most residences
only recirculate air through the HVAC system and
rely on air infiltration through the building envelope
to provide outdoor air exchanges. The portion of
outdoor air introduced through the HVAC system is
typically higher and more variable in commercial
buildings. In these buildings, the percentage of
outdoor air provided by the HVAC system may be
varied by occupancy or temperature (Althouse et al.,
1988). Thus, the rate of air exchange within the target
space (both designed and actual) as well as the source
and portions of recirculated air and outdoor makeup
air should be considered in selecting the ATU to be
used.
The volume of outdoor air (makeup air) required for
proper space conditioning is determined by the size
and use of the space (e.g., number of occupants,
background indoor air sources, whether smoking is
allowed). In general, a minimum exchange rate of
four air changes per hour is recommended; however,
as noted the recommended exchanges vary dependent
upon the use of the target space.6
When calculating the volume of treated space,
connectivity to other portions of the building through
the HVAC system should be considered. Additional
contaminant mass could be delivered to the target
space through the HVAC system and additional air
changes could be necessary. Additional mass could be
in the form of products used within the building or
from subsurface contamination extending beyond the
initially considered space. Mass contributions from
other portions of the building connected by the
HVAC must be considered as part of carbon
consumption rates.
26
m
i
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5.2.4 Power Requirements
Power requirements depend on the size and type of
ATU selected. In general, smaller residential type air
purifying units require a 100—120-volt power supply,
while larger units may require 230 volts. If an in-duct
ATU is added to the HVAC system, the filter may
add significant pressure drop, which can increase fan
energy requirements in HVAC systems and increase
operating costs. If an in-line system is used, the
potential pressure drop should be considered and the
HVAC system evaluated to determine if
modifications are needed to maintain designed
operational parameters while overcoming the added
pressure drop.
In-duct air cleaning systems will reduce the air flow
delivered in most residential forced air HVAC
systems. The effect on airflow and energy use in a
commercial system will depend on whether the
system has a constant volume or variable air volume
design. Air handlers are often set to run at a specific
pressure drop, so adding an ATU is likely to cause the
airflow to go down. Slower airflow will cause the air
to be cooled more (or heated more) but less
efficiently. But with less airflow, the system will need
to run longer to meet space temperature conditioning
requirements, increasing energy use Qung, 1987;
Nassif, 2012).
Power consumption can be estimated using the
following equation:
(kWh) =
q x AP x 11
n x 1000 I	
Where:
E = energy consumption (kWh)
q = airflow volume (m3/s)
AP = average resistance of the filter (Pascals)
t = operating hours (h)
n = fan efficiency
Depending on how the HVAC system is operated
(constant temperature or constant flow), energy
increases may result from increased run times to meet
temperature requirements rather than the pressure
drop across the filter.
5.2.5 Security Requiremen ts
Unit security is a consideration with the primary
objective of preventing occupants or trespassers from
removing, tampering with, or turning off air cleaning
units. These concerns are dependent upon the
specific conditions of the ATU deployment and of
lower concern for HVAC ATUs.
5.3 Design Process— Standalone Units
The design process incorporates the building
characteristics listed above. The design process
discussed in this subsection refers specifically to
standalone units (which can be either wall-mounted
or portable). Some different design considerations
apply for duct-mounted units as outlined in Section
5.4. Frequently, ATU sizing and selection must be
done rapidly; therefore, in many cases a detailed
evaluation of the HVAC system and cataloging of
potential mass contributions, either from subsurface
sources or indoor sources, is not feasible.
Two approaches can be used to develop ATU
specifications for a particular scenario:
1.	If more specific information is available,
conduct a mass-balance evaluation to
appropriately size the ATU.
2.	Size the ATU based on a simpler equation
that uses a multiple of the baseline air
exchanges per hour for the target space to
derive a target treatment rate for the ATU.
Temporal variability and other uncertainties should be
used for either design approach, and follow-up
sampling is recommended to confirm the
effectiveness of either approach.
Commented [YN1]: Alt text for equation:
Energy consumption (E) in kilowatt hours equals the product of
airflow volume (q) in cubic meters per second times the average
resistance of the filter (delta P) in Pascals times the operating hours
(t) divided by the product of fan efficiency (n) times 1000.
Adsorption-based Treatment Systems
27

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5.3.1 Predesign/Selection Data Collection
For the mass-balance method, the following
information is needed (specific or estimated):
•	Current indoor air concentration
•	Treatment space volume
•	Contaminant infiltration rate from the
subsurface
•	Contaminant concentration in the subsurface
(which would typically be estimated from
sub slab concentrations)
•	Outdoor air exchange rate (some information
available in U.S. EPA, 2011b)
•	Outdoor contaminant concentrations
•	Flow rate of indoor sources of contaminants
•	Concentration of indoor air sources of
contaminants
•	Exchange rate of air recirculated from an
adjacent HVAC zone to the treated zone
•	Concentration of contaminants in the air
being exchanged between adjacent zones.
For the air exchange method, the following
information is needed:
•	Treatment space volume (also consider
volume of total HVAC zone)
•	Treatment space use (to select needed air
exchanges and determine available space)
•	Flow rates for potential ATUs.
Carbon consumption estimates can be developed
more accurately if mass balance information is
available to estimate loading. Otherwise, general
assumptions can be made using current indoor air
concentrations, which under residential or office
scenarios would be expected to remain relatively
stable (within an order of magnitude). In an industrial
scenario where large volumes of VOC-containing
products are frequently used, more variability would
be expected.
5.3.2 Sizing/Number/Capacity Calculations
The equations in the following subsections have been
derived using multiple simplifying assumptions to
provide relatively simple equations for selecting a
design starting point. In real systems, every input to
the equations will vary over time and these variations
can be difficult to predict.
Concentration reductions within the target space
using ATUs would generally be expected to follow an
asymptotic curve in the period immediately after
initial activation, but before efficiency drops, as
illustrated by Figure 7.
However, variations in indoor product use, flux
across the slab due to barometric pressure changes/
temporal changes in sub slab concentrations, changes
in operation of HVAC units, and other factors will
impact both the effectiveness of treatment and
carbon saturation times.
As such, the equations presented below provide a
starting point for selecting ATUs. Follow-up
monitoring is required to confirm that the correct
number and size of ATUs has been installed for the
specific scenario as well as to monitor media
breakthrough times.
Influence on Room
•Room
¦Acceptable
Figure 7. Air treatment unit influence on indoor air concentrations
(idealized example after initial startup)
28
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Mass Balance Sizing Method
The overall mass balance can be generalized as
follows:
Mass entering the space
= mass adsorbed
+ mass exiting the space
Contaminant mass enters a space from several
primary locations:
•	Outdoor air.
•	Air recirculated from other zones within the
building.
•	Soil gas entry points.
•	VOC-containing products in use within the
target space or other VOC generating
processes, such as cooking (Huang et al.,
2011) or combustion appliances.
•	The flow rates of outdoor air exchange and
recirculated air depend on HVAC operation
and are based on the use of the space and the
number of people generally occupying the
space. Information on typical background
concentrations of many VOCs of concern in
VI is available from U.S. EPA (2011a). Data
on indoor air concentrations of a longer list of
VOCs are summarized in Appendix C of the
New York State VI guidance (New York State
Department of Health, 2006).
•	Mass generally enters a space from the
subsurface through specific entry points (e.g.,
cracks, utility lines entry points) and to a lesser
extent as diffusive flux across a slab. This
term can be estimated using subsurface
concentrations and a default soil gas entry rate
(Qs) or by direct measurements of mass flux.
Methods for mass flux estimation from VI are
discussed in Dawson and Wertz (2016) and
Guo et al. (2015).
•	Product use within a space may contribute
significant mass to the space dependent upon
use and may be more difficult to estimate.
However, if the air exchange rate is known
and a long-term integrated VOC sample is
acquired for a full list of VOCs, an estimate
may be obtained.
It should be recognized that concentrations and flow
rates change temporally. However, in the following
equations, pseudo-steady state conditions are assumed
as a simple way to make initial estimates. This
approach uses a constant removal rate for the air
cleaner based on the value it would have at the initial
room concentration, Q^rifCi. This estimate allows us
to avoid the complicated equations that describe the
actual non-steady state situation, while providing an
acceptable estimate for an initial assessment.
Figure 8 is a representative depiction of the mass
balance inputs used in the following equation:
| Qo^o + Qrl^rl + Qs^s + QpCp
= QfnfCi + Qr2Cr2 + Qe^e [
Where:
Q0 — outdoor air flow rate
C0 — outdoor air concentration
Qd = air flow rate from target space to adjacent
space
Cri = air concentration in air moving from target
space to adjacent space
Qr2 — air flow rate from adjacent space to target
space
Cr2 — air concentration in air moving from adjacent
space to target space
Qs — subsurface soil gas infiltration rate
Cs — subsurface soil gas concentration
Qp = product flow rate
Cp = product concentration
Qf= air filter flow rate
nf= air filter efficiency
C; = starting indoor air concentration
Qe = flow rate of air exiting target space through
the building envelope
Ce = concentration of air exiting target space (i.e.,
after filtration).
Commented [YN2]: Alt text for equation:
This equation is related to the model depicted in Figure 8. Outdoor
air flow rate times the outdoor air concentration plus the air flow rate
from the target space to the adjacent space times the air
concentration in air moving from the target space to the adjacent
space plus the subsurface soil gas infiltration rate times the
subsurface soil gas concentration plus the product flow rate times the
product concentration equals the air filter flow rate times the air
filter efficiency times the starting indoor air concentration plus air
flow rate fiom adjacent space to target space times air flow rate from
adjacent space to target space plus flow rate of air exiting target
space through the building envelope times concentration of air
exiting target space (i.e., after filtration).
Adsorption-based Treatment Systems
29

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Indoor Product

QpCp Target
* Zone
at.
Air Cleaner
dp.
Adjacent
Zone
Q0 =
This equation can then give a starting point for
selecting an ATU and is similar to that previously
derived in Howard-Reed et al. (2007). A hypothetical
example is provided in Table 6 and Figures 9—11.
For each scenario, all parameters are the same except
for the starting indoor air concentration and the
sub slab concentration. Starting indoor air
concentrations were determined by allowing the
indoor concentration to reach steady state with the
ATU off (Qf=0). Scenario 3 shows the required ATU
flow rate under the same conditions as Scenario 2. A
spreadsheet was set up to calculate indoor air
concentrations over time using a mass balance and
assuming no indoor air sources, one HVAC zone, and
perfect mixing within that zone. The inputs for each
scenario are provided in Table 6. The results of each
analysis are provided as Figures 9—11. an indoor
source without a sub slab source). However, it should
be used with caution and it is suggested to add
uncertainty factors to address potential indoor
sources and to address temporal changes.
V x ACH\	As noted in Section 4.2, the sub slab soil vapor
—concentration, and by association the mass flux from—
Figure 8. Representative depiction of mass balance inputs
In most office and residential scenarios, where only
one HVAC zone is present, then the terms involving
Qri, and Qr2 are eliminated as zero.
If the number of air exchanges is known or estimated,
the flow rate of outdoor air (Qo) into the space can be
estimated using the following:
60
Where:
V = volume (ft3)
ACH = air changes per hour.
The term (C;) is the starting indoor concentration,
with Ce being the target indoor concentration after
treatment. Using a simplifying assumption that there
are no indoor sources and that the flow rates in and
out of the structure are essentially equal (Q0 — Qe)
because the flow through the slab is much smaller
than the flow through the exterior walls, the equation
becomes:
V x ACH
QfKfCi = —— (C0 — Cg) + QSCS
Or rearranging to:
Qfnf =
VxACH ,
60
the subsurface (QSCS), is shown in this formulation.
In Scenario 1, the mass balance indicates that an air
filter with a flow rate of 50 cfm and an efficiency of
80% (0.80 in fractional terms) will reduce the indoor
air concentration of the target space to below the
target level. However, if the subslab concentration is
increased only moderately from 200 ppb to 1,000 ppb
(Scenario 2), the starting equilibrium indoor
concentration and same ATU will barely reduce the
indoor air concentration as shown in Figure 10.
However, if the ATU flow rate increases to 350 cfm,
the target concentration can be achieved despite the
stronger subslab and initial indoor concentration
(Scenario 3; Figure 11). This exercise demonstrates
the importance of subsurface contributions when
sizing ATUs for specific conditions. This is supported
by analysis of the data collected at Bethpage,
discussed in Section 4.2.
Commented [YN3]: Alt text for equation:
Flow rate of outdoor air (Qo) equals the volume (V) in cubic feet
times the air changes per hour (ACH) divided by 60
c<
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Adsorption-based Treatment Systems

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Table 6. Summary of Scenario Input Parameters
Parameter
Scenario 1
(base case)
Scenario 2
(stronger source)
Scenario 3
(stronger source, larger air
treatment unit flow rate)
Initial Indoor Air Concentration (C)
21 ppb
52 ppb
52 ppb
Target Space Air Volume (V)
1,000 ft3
1,000 fp
¦1,00.0*
Subsurface Infiltration Rate (Qs)
4 cfm
4 cfm
4 cfm
Subsurface Concentration (Cs)
200 ppb
1,000 ppb
1,000 ppb
Outdoor Air Concentration (Co)
0 ppb
Oppb
0 ppb
Air Changes per Hour (ACH)
2
2
2
Air Treatment Unit Flow Rate (Qf)
50 cfm
50 cfm
350 cfm
Air Treatment Unit Efficiency (m)
0.80 (80%)
0.80 (80%)
0.80(80%)
Target Indoor Air Concentration (Ce)
14 ppb
14 ppb
14 ppb
Influence on Room
loom
Acceptable
B 20.0
20 40 60 80 100 120 140
Time (min)
Figure 9. Results of Scenario 1 after air treatment unit startup
(base case)
a 50 0
3
8 10.0
K
c 30,0
1
1 20 0
o
| 10.0
0.0
Influence on Room
—Acceptable
¦Room
Time (min)
Influence on Room
600
o. 50.0
a
| 40.0
OS
C 30 0
o
to
•| 20.0
v
8 100
0.0
1




•^Room
	Acceptable
F














60 80
Time (min)
Figure 11. Results of Scenario 3 after startup, stronger source,
larger air treatment unit flow rate.
Figure 10. Results of Scenario 2 after air treatment unit startup
(stronger source)
Adsorption-based Treatment Systems
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Air Exchange Sizing Method
For the air exchange method, a target air exchange for
the ATU or ATUs is set (ACHt) and the size and
number of ATUs needed can be calculated as follows:
# of ATUs = ¦
V x ACHt
60
¦ -i- (ATU flow rate x n^)
In this case, the ACHt is the target for given space for
the ATUs (i.e., the ATU or units will produce the
desired number of air changes per hour). In general, a
total target ATU flow rate (produced from one or
multiple units) of approximately 4 to 5 times the flow
rate of outdoor air (Qc) (the baseline fresh air
exchange rate) will be sufficient to address
contributions from a sub slab source with low-to-
moderate VOC concentrations. The ratio of ATU
flow rate to the flow rate of outdoor air required will
increase for high sub slab source strength.
Additionally, if indoor sources are known to be
present, the ratio should be increased.
This calculation estimates the number of ATUs
required for a specified flow rate. It is important to
consider the noise level produced by each ATU when
selecting the flow rate for calculation. For example,
the maximum flow rate of a given ATU may be 300
cfm; however, operation of the treatment unit at this
rate may produce noise levels that are not tolerable to
occupants. Therefore, in this case, a lower operation
rate should be assumed.
5.3.3 Air Treatm en t Un it Efficien cy Calculation s
Air treatment unit efficiency is defined based on the
difference between the inlet concentration and the
outlet concentration based on the following equation:
¦fz
Where:
nf = air treatment unit efficiency (fractional)
G = air treatment unit inlet concentration
G — air treatment unit outlet concentration
It should be expected that as the carbon becomes
saturated, ATU efficiencies will decrease.
5.3.4	Sourcing/Procurement/Contracting
The source of a particular ATU depends on the type
of unit selected. Residential-sized standalone units are
widely available commercially and are relatively low	
cost (typically < $1,000). Larger units can be rented or
purchased from specialty suppliers. When deciding
whether to rent or purchase a specific ATU, the life-
cycle cost as well as client/homeowner preferences
should be considered. The decision between renting
and purchasing will also be influenced by the
anticipated time of operation before a more long-term
mitigation or remediation system is installed and
becomes effective.
A list of potential vendors is included with the
equipment information in Attachment A.
5.3.5	Permitting/In sp ection Requirem en ts
In general, permits are not required for portable ATU
systems that are plugged in and not hard-wired to a
power source. However, if a powered in-duct system
or hardwired system is selected, check local
jurisdictions for specific requirements. Potential
permitting inspections could include a building
permit, HVAC inspection, and electrical permit or
inspection.
5.4 Design Process—Differences for Duct-
Mounted Systems
Similar mass balance concepts to those discussed in
Section 5.3 for standalone systems could be applied to
duct-mounted systems. However, in most retrofitted
duct-mounted applications, the airflow of the duct is
(Ci — Cg)I not a variable that the designer has full control over.
Q |	As discussed above, it will be influenced by the	
existing air handler and its control algorithm. So
similar mathematical approaches may allow estimation
of the resulting indoor air concentration, but there
may be limitations on the ability to achieve a target
level of treatment.
Commented [YN4]: Alt text for equation:
The number of air treatment units (ATUs) equals the volume (V) in
cubic feet times the target air exchange for the ATUs (ACHt))
divided by 60. That result is divided by the product of the ATU flow
rate times the fractional air treatment unit efficiency (nf)
Commented [YN5]: Alt text for equation:
Fractional air treatment unit efficiency (nf) equals the result of air
treatment unit inlet concentration (Q) minus air treatment unit outlet
concentration (Ce) divided by air treatment unit inlet concentration.
32
Adsorption-based Treatment Systems

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For in-duct HVAC applications, if a system can
accommodate a thick filter or supplemental filter (for
example, a box filter or V-bank filter, which are
commonly 12" deep and are found in many
commercial buildings), a deep filter is recommended
as the deeper depth should provide more sorbent
media and is recommended for higher efficiency and
longer life. Major manufacturers generally
recommend speaking to a technical salesperson for
assistance in selecting the right sorbent for your site.
Manufacturers' technical representatives should know
the test data for their products and the influence of
variables such as temperature, humidity, source
variability, and HVAC design on filtration
performance. A buyer should use the information in
this document as a reality check for the selection
advice given by such a manufacturer's representative
and should contact multiple manufacturers.
For HVAC system installations, ATU sizing
considerations are mainly based on estimated carbon
consumption rates; in other words, they are based on
concentrations of VOCs in indoor and outdoor air.
For an HVAC application that can only accommodate
a thin filter (i.e., 1" to 2"), calculations are likely to
show that the sorbent will be rapidly consumed.
However, this may still be a good option for locations
with low-level sources, only slightly out of
specification concentrations, and a willingness to
change a filter every 1 to 3 months (as is usual for a
residential particle filter or a commercial building
particles-only pre filter). This may also be a good quick
improvement while waiting for a better ATU to
arrive.
5.5 Air Treatment Unit Deployment
The complexity of deploying ATUs to a site varies
depending on the scale of indoor air problems being
addressed. When the plan calls for a few, small
portable units, deployment consists of placing the
units within the space and starting them following the
manufacturer's directions. The complexity increases
as more or larger units are required. Examples
include:
•	The electrical demands increase as more units
are used within a space. It may be necessary to
consult an electrician or electrical engineer to
assess whether sufficient power is safely
available given the demands of the ATUs and
existing electrical equipment. Attention
should be paid to which circuits the ATUs are
using, the rated capacity of those circuits, and
what equipment is already connected to those
circuits. Note that it is common for motorized
electrical devices to require more current at
startup than in routine operation.
•	Larger portable units may not be suitable for
placement directly into the space being treated
because of noise generation or space
requirements, so temporary ducting may be
required.
•	Larger, built-in systems are the most complex
and may require the involvement of engineers
and tradespeople from mechanical, electrical,
and other disciplines. Deployment of such
systems could involve significant construction
work, which will likely require building
permits, and could require temporary
suspension of normal operations within the
space being treated.
•	Adding an in-duct supplemental filter or
changing the HVAC filter may be simple, but
the energy costs must be considered.
The positioning of ATUs within a space requires
consideration of three key factors:
•	Minimizing disruption of normal use of the
space. The equipment and power cords
should be placed where they will not cause
tripping hazards or otherwise disrupt people's
movements. Particular attention is warranted
when mobility-impaired people are or could
be present; consultation with an adaptive-
design specialist may be necessary.
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33

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•	To minimize occupants' discomfort due to
noise, the units should be placed as far as
practical from locations where occupants
spend large amounts of time. In occupational
settings, this could include being away from
desks or other workstations. In a residential
setting, this could include avoiding proximity
to dining tables, kitchen work areas, sofas,
chairs, and beds.
•	As discussed previously, the results from the
testing conducted by Ho ward-Reed et al.
(2007, 2008a) imply that it is beneficial to
locate the unit in the same room that soil gas
is entering. It is also necessary to place the
unit so it has free air circulation, and the
treated air is rapidly mixed with the bulk of
the air in the targeted zone.
Startup of small portable units can be as simple as
turning the fan on to the desired speed setting and
confirming that air if flowing through the unit.
Startup of larger and built-in units will be more
complex, especially if the air is to be ducted into
existing ductwork or if a supplemental filter is to be
introduced into the existing ductwork that markedly
changes the flow. In that case, startup will likely
involve rebalancing of airflow, requiring the expertise
of a knowledgeable mechanical engineer or technician
(National Environmental Balancing Bureau, 2005).
5.5.1 Verification Testing an d Perform an ce
Monitoring
Verification and ongoing performance testing is a
requirement following ATU deployment and startup.
Although the ATU mitigation may have been
specified with a conservatively high airflow rate, no
system can be assumed to be operating as intended
without collecting and analyzing indoor air VOC
samples. Also, as the system operates and the sorbent
gets loaded with VOCs, the potential for VOC
breakthrough and desorption increases. Therefore,
some type of ongoing performance monitoring is
required.
The sampling and analytical methods for verification
and operational monitoring typically consist of time-
weighted samples collected in the breathing zone, that
is, 3 to 5 feet above the floor within the space of
interest. The sampling location should be selected to
be well away from the air cleaning device. Sample
durations can vary from hours to days. Some current
sampling strategies may include the following:
•	Collecting 8-hour indoor air samples in
occupational settings using U.S. EPA Method
TO-15
•	Collecting 24-hour air indoor air samples in
residential settings using U.S. EPA Method
TO-15
•	Collecting 7-day or longer indoor air samples
using passive-diffusion samplers and U.S.
EPA Method TO-17.
Selection of a sample duration and methods is a
project-specific decision. Initial verification samples
typically match the duration and methods used to
collect the investigation samples that led to the need
for mitigation. The strategy may be changed as the
goal changes to long-term monitoring.
Initial verification samples are collected after an
equilibration period of 24 to 48 hours following ATU
startup. If the initial verification samples show indoor
air VOC concentrations below applicable thresholds,
such as project action levels, then the monitoring
program transitions to operational monitoring. If the
VOC concentration exceed thresholds, then
modification to the system may be required followed
by additional verification sampling.
The frequency of operational indoor air monitoring is
a function of two main factors: the anticipated time
for VOC breakthrough and the presence of other
indoor air contaminants that may influence ATU
performance. An example of the latter, as discussed in
Section 5.1, is nontarget VOCs present in indoor air,
which may consume sorption capacity and reduce the
lifetime of the sorbent. Another example is airborne
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particles. Most ATUs include some type of prefilter to
remove particulates prior to the sorbent material.
Often high-efficiency particle air (HEPA) filters or
other fine-particulate filtration media is used. Such
filter media may become clogged resulting in
decreased airflow and air-cleaning efficiency over
time. Due to these factors, it is prudent to include a
margin of safety when selecting a sampling frequency.
For example, if breakthrough is calculated to take 1
year, then quarterly monitoring could provide
sufficient resolution to see breakthrough in advance
of the expected time. The monitoring frequency could
be reduced once the breakthrough period is
understood through two or more cycles of sorption
media change out with site-specific data collection.
5.5.2 Op eration an d Main ten ance
ATU equipment requires ongoing routine
maintenance. The user manuals will provide detailed
information for a specific unit. General operations
and maintenance procedures include:
•	Inspections to verify that the equipment is in
place and running at the intended air flow.
While this may seem like a simple procedure,
experience has shown that it may be the most
critical inspection criterion. Building
occupants may turn off, move, or unplug
portable ATUs for various reasons including
noise (Lawrence Berkley National Lab, 2016),
access of areas for cleaning, or lack of
understanding of the equipment*s purpose.
With more permanent, built-in systems, data
loggers and telemetry may be incorporated to
verify system uptime.
•	Checking the seating of the filters. Many
portable units have filters that are loosely
mounted. It is important that they be in the
correct place so that the air does not
inadvertently bypass the filter.
•	Replacing pre filters at the frequency
recommended by the manufacturer or more
frequently if airflow is reduced due to high
concentrations of particulates.
•	Replacing the VOC filtration media. The
operational air monitoring data will provide
information on trends of the target analytes.
Media change out can be specified for when
the monitoring data shows concentrations of
target analytes at some fraction, say 50% or
75%, of the site-specific action level. This will
minimize the potential for breakthrough prior
to the subsequent monitoring event.
•	Cleaning. Keeping the exterior of the ATU
clean will improve its aesthetic appeal.
Because VOC filtration media will accumulate VOC
mass, it is possible that spent media could meet state
or federal criteria for characterization as hazardous
waste. Testing, such as EPA's Toxicity Characteristic
Leachate Procedure (TCLP), may be necessary to
support waste characterization. A waste management
specialist should be consulted to evaluate this
possibility and develop waste characterization and
management plan. Prefilter media will typically be
managed as non-hazardous waste and disposed of as
municipal solid waste.
The need for ATUs may end for reasons such as the
following:
•	A longer-term mitigation system has been
installed. For example, a subslab
depressurization system maybe installed
when VI is the cause of indoor air
contamination.
•	Environmental remediation has diminished
the source of VOCs to the point where
mitigation is no longer required.
When portable equipment is used, demobilization
may be as simple as removing the equipment from
the building and managing spent media appropriately.
Removal of a built-in system may be as significant an
effort as the original installation. Building owners or
operators may prefer to leave the equipment in place
Adsorption-based Treatment Systems
35

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to improve indoor air quality issues unrelated to
environmental contamination. In such cases,
ownership and responsibility for operations and
maintenance will typically be transferred to the owner
or operator.
5.6 Communication and Instructions for
Occupants During Air Treatment Unit
Depioyment and Operation
Communication with building owners, operators, and
occupants is key to successful deployment and
operation of ATUs. For environmental clean-up
projects, this will likely take place as part of a larger
property access and stakeholder-communication
effort. Some examples of needed communication
regarding ATUs include the following:
•	Informing stakeholders that use of ATUs may
be implemented if results from planned
indoor air VOC samples exceed applicable
thresholds. This is particularly important if the
need for a rapid response is a possibility (rapid
responses were performed in many of the
applications discussed previously in Section
4.3). In such cases, it may be most efficient to
include the potential deployment of ATUs
into the agreement used to gain access to the
property for sampling. Including pictures and
other information about the units may ease
communication with stakeholders.
•	If portable ATUs are being deployed,
outreach to building occupants, maintenance
staff, and others with access to the units is
important. As noted in Section 5.5, people
turning the units off, unplugging them, or
removing them is a common problem.
Regular inspections can help minimize such
events, but educated occupants are the first
line of defense. Direct, face-to-face education,
wall signs, and other methods can be used to
educate occupants about the purpose of the
ATUs and the importance of their continuous
operation to maintaining indoor air quality.
•	If deployment of built-in or in-duct ATUs is a
possibility, it will be important to identify
decision makers early in the process. In
commercial settings in particular, the decision-
making authority may be complex and could
involve owners, property managers, and the
businesses leasing the property. Workers'
unions may also require notification in
commercial and industrial setting.
•	Establishing a clear line of communication for
occupants to report problems with the ATUs
during operations is important. This can take
the form of stickers or wall notices placed on
or near the units. It may also be beneficial to
place property tags on the equipment that
clearly identify the equipment owner with
contact phone numbers. Portable ATUs have
gone missing during deployment and property
tags could aid in recovering the equipment.
Identifying these and other communications needs
and establishing a communications plan early in the
project planning process will facilitate a more
successful project.
6. MONITORING AND VERIFYING AIR
TREATMENT UNIT PERFORMANCE
Since the performance of VOC ATUs can decline
over time for various reasons, including saturation of
the sorbent media, increases in VOC sources, and
changes in building flow regimes, a monitoring
program is needed to verify that performance
objectives are met. Performance objectives for a VOC
ATU installation can be specified in several ways, but
the primary ones are:
•	Maintenance of indoor air concentrations
below pre-specified standards
•	ATU efficiency (concentration out over
concentration in)
•	ATU placement and continued operation
36
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Adsorption-based Treatment Systems

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•	Reduction of indoor air concentration while a
longer-term mitigation solution is being
installed.
As detailed in Section 5.5.1, the desired performance
objectives can be monitored in several ways including:
•	Regular VOC monitoring by measuring
indoor air VOC concentrations (to check for
exceedances of the specified standards), or
VOC concentrations at the ATU inlet and
outlet (to check on VOC removal efficiency).
•	Scheduled check-ins (visits and calls) before
and after installation to ensure that the system
is and remains correctly installed and
operated. For example, for residential
installations, it may be prudent to contact the
homeowner within a few days of installation
to ensure that the ATU is still operational
(e.g., is it plugged in? Is air coming out of the
discharge?) and has not caused issues such as
excessive noise. Check-in visits can also
inspect the premises to help identify changes
in HVAC operations or building
modifications that could adversely affect
treatment unit operation and performance.
•	Contacts for the building occupants in case of
problems with the units.
When developing a monitoring plan, performance
objectives should also be expressed in terms of data
quality objectives (DQOs) that specify the type,
amount, and quality of indoor air quality data that
needs to be collected to verify performance at the
specific location of interest, including how samples
will be collected and analyzed. For example, DQOs
for a commercial building might specify 8-hour
summa canister (Method TO-15) samples for short-
term VOC concentration checks while DQOs for a
residential setting may specify 24-hour samples to
accommodate the longer exposure period.
An ATU monitoring plan should be consistent with
the indoor air sampling plan that was used to identify
the indoor air problem and select VOC ATUs as part
of the solution, with the original indoor air sampling
establishing the baseline that will be compared to the
ATU monitoring results. This monitoring plan can
include sampling frequency and locations (for
comparability), although ATU placement will
influence sampling locations (for example inlet and
outlet samples for efficiency measurements).
In addition, the monitoring plan should specify an
end date for sampling, based on site-specific estimates
or measurements of when VOC concentrations may
fall below concentrations of concern. This may
involve different sampling frequencies during
treatment system operation, such as specifying 2-week
or 1-month passive samplers (U.S. EPA, 2015) for
longer operations with TO-15 samples at the
beginning and end of operation, or when
concentration increases are identified from passive
samplers or field VOC sensor measurements.
Although they do not provide compound-specific
data, field VOC sensors (e.g., photo- or flame-
ionization detectors) may also be useful in identifying
VOC sources associated with VOC increases
identified during routine VOC monitoring.
Finally, specifications of sampling and analysis
techniques should be appropriate for the problem and
consistent with what is being used by the regional or
state regulatory authorities.
7. CURRENT CHALLENGES, LIMITATIONS,
AND RESEARCH AND DEVELOPMENT
NEEDS
As shown in the examples and data presented in
Section 4.3, there has been considerable variability in
the effectiveness of the practical applications of
ATUs to vapor intrusion. Most field applications have
been to rapid action cases and have relied on rules of
thumb rather than computational engineering design
approaches.
Adsorption-based Treatment Systems
37

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The best field-scale, measurement-based testing
program results found reported in Section 4.2 were
for decane, not the chlorinated or aromatic
hydrocarbons that drive the vast majority of U.S.
vapor intrusion sites. That test program employed a
constant indoor source of the test VOC, and; thus,
did not test the complex set of geologic and
meteorological factors that control VI behavior in
buildings (U.S. EPA, 2012).
As exemplified by the publications of the California
Air Resources Board (2016), not all currently
marketed ATUs can be recommended for use. Some
of the devices are ineffective or produce excessive
ozone. There have not been adequate field
demonstrations of photocatalytic ATUs in complex
real indoor atmospheres with trace VOCs, such as are
found at VI sites, to fully evaluate whether any
observed destruction of target VOCs outweighs the
formation of undesirable reaction byproducts in some
designs. Therefore, the use of sorbent-based VOC
ATUs in current applications is preferred and
suggest that the photocatalytic devices merit
additional testing.
7.1 Technology Development and Chamber
Verification Needs
7.1.1 Future Technology Development
Although carbon filtration for VI contamination
removal is most effective at this point, there are many
technologies that could eventually be developed to
successfully remove VOCs from indoor air.
Specifically treated sorbents designed for chlorinated
hydrocarbons could be developed. Systems using
currently available sorbents could be designed to
allow periodic stripping of sorbed compounds to
increase lifetime and yield better prediction of
performance. Reactive ATU technologies are still
relatively new and newer designs could lead to units
with predictable byproducts or extremely short half-
life intermediates that are not problematic.
7.1.2	Potential Duct-Testing Programs
Duct-testing apparatuses can be used to directly test
replacement filters and similar devices that are directly
installed in existing HVAC systems. These
apparatuses can also be used to test the filter or
sorbent components of portable or wall-mounted
ATUs (dismounted from the portable equipment).
Single-pass efficiency and capacity information is
extremely useful in ranking devices for performance.
Testing of units based on the ASHRAE 145.2 test
should be done. Simply testing more commercially
available units with a VI-relevant chlorinated
hydrocarbon would increase our knowledge of how
these units work relative to each other. These data
used in modeling would allow improved calculations
of the likely effectiveness of the devices.
Another useful approach using duct testing would be
to use a mixture of VOCs typically found in VI
situations, considering both soil gas and indoor air
background VOCs. This testing could be conducted
at typical concentrations observed in the field, but as
low as needed to include regulatory limits. Testing
could also be conducted at standard and high
humidity, to include conditions common to
basements and crawlspaces, low income communities
where air conditioning may not be universal, and high
humidity spaces such as bathrooms and kitchens.
Although this approach would not give exact
information for every situation, it could provide very
different answers than provided by the single-
compound, typical condition testing. A measurement-
based pilot study of representative units could
determine whether all units should be tested this way.
7.1.3	Poten tial Chamb er- Testin g Programs
Chamber testing is used for portable and wall-
mounted units. Chamber testing specifically allows
multiple passes of air through the ATUs. HVAC
units should be scaled to the size of the room.
Chamber testing is needed, especially for small
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Adsorption-based Treatment Systems

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devices with low airflow that cannot be tested using
the duct-testing method.
A chamber test could start with a single injection of a
contaminant or set of contaminants, continuous
injection, pulsed injection, or even injection with
changing characteristics over time, which could be
helpful in emulating VI situations. Chamber testing
using high sensitivity analysis could detect byproduct
compounds that might not be seen in duct testing as
they may be concentrated over time in the chamber.
Conditions such as humidity and various
concentrations of mixed VOCs and inorganic gases
can be tested.
For the future development of reactive devices,
chamber testing allows for the multiple passes and
time for reactions to occur and be completed. Testing
can then determine both reaction intermediaries that
might be unacceptable and capability to actually
destroy contaminants.
7.2 Field-Scale Testing, Verification, and
Tech Transfer Recommendations
7.2.1 Quantitative Reviews of Existing Field
Applications
Existing applications are generally managed only to
meet the human health protection, regulatory
compliance, and economic needs of a situation.
Therefore, data that may be helpful in designing
future applications of the devices are generally not
systematically gathered, reported, or analyzed.
However, more analysis using the mathematical
approaches outlined in this paper (and in Howard-
Reed et al., 2008a, b) is possible. Information on
building volumes while not frequently reported could
be easily gathered. Records of operational runtime as
well as concentrations found on sorbent beds prior to
disposal are other valuable information that may be
gathered. Comparison of existing sub slab
concentration data to indoor air performance would
be valuable. Applications funded by government
potentially responsible parties or EPA Regions, and
data already in the public record, may be amenable to
additional systematic analysis.
Buildings with ongoing applications could be
approached to allow the measurement of key
parameters such as air exchange rates and indoor
humidity. Indoor source surveys might also be
undertaken with field instruments, such as the
HAP SITE gas chromatograph/mass spectrometer
system, to understand performance differences
between buildings. In government-funded or
controlled cases, collection of additional indoor air
quality data to provide more time resolution or source
strength information may be feasible.
Such applications have the benefit of realism with
varying weather conditions and VOC-generating
indoor activities. However, with that realism also
comes more potentially confounding variables to
analyze. Additionally, systems in occupied buildings
cannot be run to breakthrough or other failure
modes.
7.2.2 Field-Scale Demonstrations
Studies in normally constructed, but currently
unoccupied structures, have been informative to the
VI field. Tests of ATU performance in such
structures have been previously performed by
Howard-Reed for indoor sources. Ideally a building
that has concentrations of VOCs from vapor
intrusion that might require rapid response in an
occupied building could be selected. Such a structure
could be carefully instrumented to observe air
exchange rate, soil gas entry rate (i.e., with radon
tracer), time-resolved VOC concentrations, humidity,
and other factors. Tests could be done initially
without indoor sources. Later, indoor sources (i.e., air
fresheners, loosely capped solvent containers, shower
water) could be introduced in a controlled manner.
Testing could be conducted with and without air
conditioning or dehumidification.
Multiple ATUs or multiple flow settings could be
tested to validate the mathematical design approaches
Adsorption-based Treatment Systems
39

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presented in this EIP. Additional spreadsheet
scenarios, such as those presented in Table 6, could
be developed as a technology transfer/training tool.
The ability of such a simple spreadsheet model to
provide useful design guidance could be explored by
comparison to results of more complex models. More
complex models, such as the NIST multizone indoor
air quality model CONTAM7 or a three-dimensional
or transient VI model, could provide the ability to
explore the sensitivity of ATU performance to
variations in environmental conditions.
NOTICE
The information in this document has been funded
wholly by the United States Environmental
Protection Agency under contract number EP-C-11-
036 to RTI International. It has been subjected to the
Agency's peer and administrative review and has been
approved for publication as an EPA document.
Mention of trade names or commercial products does
not constitute endorsement or recommendation
for use.
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Kesselmeier, J., and M. Staudt. 1999. Biogenic volatile
organic compounds (VOC): An overview on emission,
physiology and ecology. Journal of Atmospheric Chemistry
33(1):23—88.
Kropp, R. 2014. Applications of Photo-Active Thin Film
Semiconductors in Environmental Remediation. PhD
Dissertation. University of Wisconsin-Madison.
Lawrence Berkley National Laboratory. 2016. Indoor
Environment Group, Scientific Finding Resource
Bank, Frequently Asked Questions, https://iaqscience.
lbl.gov/faq. accessed October 14, 2016.
Lee, P. and J. Davidson. 1999. Evaluation of activated
carbon filters for removal of ozone at the ppb level.
American Industrial Hygiene Association Journal 60 (5):589—
600.
Lee, C.S., F. Haghighat, and A. Bahloul. 2016. What are
the hurdles in effective implementation of PCO
systems in AHU? IAQVEC 2016, 9th International
Conference on Indoor Air Quality Ventilation &
Energy Conservation in Buildings. Seoul, Korea.
McDermott, H.L., and J.C. Arnell. 1954. Charcoal sorption
studies II. The sorption of water by hydrogen-treated
charcoal. Journal of Physical Chemistry 58:492—498.
Mo, J., Y. Zhang, Q. Xu, J.J. Lamson, and R. Zhao. 2009.
Photocatalytic purification of volatile organic
compounds in indoor air: A literature review,
Atmospheric Environment 43:2229—2246.
Mo, J., Y. Zhang, and Q. Xu. 2013. Effect of water vapor
on the by-products and decomposition rate of ppb -
level toluene by photocatalytic oxidation. Applied
Catalysis B: Environmental 132—133:212—218.
Moyer, E.S. 1983. Review of influential factors affecting
the performance of organic vapor air-purifying
respirator cartridges. American Industrial Hygiene
Association Journal 44:46—51.
42
I
Adsorption-based Treatment Systems

-------
Murphy, J., and T.W. Morgan. 2006. Availability, reliability,
and survivability: An introduction and some
contractual implications. CrossTalk: The Journal of
Defense Software Engineering
Myrefelt, S. 2004, October. Reliability and functional
availability of HVAC systems. Proceedings of the
Fourth International Conference for Enhanced
Building Operations, Pans, http:/ /oaktrust.library.tam
u.edu/bitstream /handle/1969.1/503 l/ESL-IC-04-10-
07.pdf?sequence=4&isAllowed=y. accessed October
10, 2016.
Nassif, N. 2012. The impact of air filter pressure drop on
the performance of typical air-conditioning systems.
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Procedural Standards for Testing and Adjusting and
Balancing of Environmental Systems, 7th Edition
Gaithersburg, MD.
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relative humidity and temperature. American Industrial
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State of New York, October.
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476d-b2ee-3e252d8bd739
Owen, M.K. 1996. The Effect of Relative Humidity on Toluene
Adsorption by Activated Carbon. Masters of Science
Technical Report, the University of North Carolina at
Chapel Hill, Chapel Hill, NC.
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Efficiency and capacity test results for five gas-phase
air cleaners. Conference Proceedings for the ASHRAE
Annual Conference, New York, NY.
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phase air cleaners for use in HVAC systems. Proceedings
of AFS Next Generation Filter Media Conference, p. 1—13.
Chicago.
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Ventilation characterization of a new manufactured
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Conference, Ventilation, Humidity Control and
Energy, pp. 295-300.
RTI. 2009. Office VOC Mixture Test Report, prepared for
Genesis Air. Downloaded from the Genesis Air
Website on July 20, 2016.
Shaughnessy, R.J., E. Levetin, J. Blocker, and K.L.
Sublette. 1994. Effectiveness of portable indoor air
cleaners: Sensory testing results. Indoor Air 4(y):119—
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Shepherd, A. 2001, May. Activated carbon adsorption for
treatment of VOC emissions. 13th Annual
EnviroExpo, Boston, MA. http://www.carbtrol.com/
image s / white-papers / voc.pdf
Stampfer, J.F. 1982. Respirator canister evaluation for nine
selected organic vapors. American Industrial Hygiene
Association Journal 43:319—328.
TetraTech. 2010, November. Final Quarterly Data
Summary Report for Soil Vapor Intrusion Monitoring
(May-August 2010) NWIRP Bethpage, NY.
http: / /www.navfac.navy.mil/niris/MID ATLANTIC
/BETHPAGE NWIRP/N90845 001199.pdf
U.S. EPA. 1998, June. Carbon Adsorption for Control of
VOC Emissions: Theory and Full Scale Performance,
EPA-450/3-88-012.
U.S. EPA. 2008, October. Indoor Air Vapor Intrusion
Mitigation Approaches, EPA/600/R-08-115.
U.S. EPA. 201 la, June. Background Indoor Air
Concentrations of Volatile Organic Compounds in
North American Residences (1990—2005): A
Compilation of Statistics for Assessing Vapor
Intrusion, EPA 530-R-10-0111.
U.S. EPA. 2011b, September. Exposure Factors
Handbook: 2011 Edition, EPA/600/R-090/052F.
U.S. EPA. 2012, February. Conceptual Model Scenarios
for the Vapor Intrusion Pathway, EPA 530-R-10-003.
Office of Solid Waste and Emergency Response,
Washington, DC.
Adsorption-based Treatment Systems
43

-------
U.S. EPA. 2015. OSWER Technical Guide for Assessing
and Mitigating the Vapor Intrusion Pathway from
Subsurface Vapor Sources to Indoor Air. OSWER
Publication 9200.2-154. Office of Solid Waste and
Emergency Response, Washington, DC.
VanOsdell, D.W., Owen, M.K., and L.B. Jaffe. 1996, July.
Evaluation of Test Methods for Determining the
Effectiveness and Capacity of Gas-Phase Air Filtration
Equipment for Indoor Air Applications. Phase II: A
Laboratory Study to Support the Development of
Standard Test Methods. Final Report 792-RP.
American Society of Heating, Refrigerating, and Air-
Co nditioning Engineers, Atlanta, GA. 63 pages.
Weisel, C.P., Alimokhtan, S., & Sanders, P.F. (2008).
Indoor air VOC concentrations in suburban and rural
New Jersey. Environmental Science & Technology,
42(22) :8231—823 8.
Werner, M.D. 1985. The effects of relative humidity on the
vapor phase adsorption of tnchloroethylene by
activated carbon. American Industrial Hygiene Association
Journal 46:585—590.
44
I
Adsorption-based Treatment Systems

-------
ATTACHMENT A
AVAILABLE VOC AIR CLEANER EQUIPMENT
Adsorption-based Treatment Systems
I

-------
o>
Image
Brand
Name
Model
Installation Type
Manufacturer
Manufacture
Country
Website

11 "n
KP&mm

Aerus
Sanctuairy by
Aerus !n-Duct
Whole House Air
Purifier
Built in. Ducted
Aerus

htto://www. aerushome.com/Site/Air


J
i
Air Oasis
Large commercial
models
Portable Not ducted
Air Oasis
USA
httc://www. airoasis.com/shoD/air-oasis-
5000oro


m

Air Quality
Engineering
M66R&L
Built in. Ductable or not
ducted.
Air Quality
Engineering

httc://www. air-aualitv-ena.com/







1

0

Air Quality
Engineering
M73
Portable Not ducted
Air Quality
Engineering

httc://www air-aualitv-ena.com/
i
'
s iy
n

Airgle
AG950 PurePal
Multigas Air
Purifier
Portable. Not ducted
Airgle
China
httD://www airale.com/



AirPura
C600 DLX Air
Purifier
Portable. Not ducted
Airpura Industries
Canada
htto://ai roura.com/index. html

-------
Image
Brand
Name
Model
Installation Type
Manufacturer
Manufacture
Country
Website
Airpura
R600 All Purpose
Portable. Not ducted
Airpura Industries
Canada
http://www.airpura.com/
Alen
ET
Breathesmart-
HEPA-FreshPlus
Portable Not ducted
Alen
https://www.alencorp.com/collections/air-
punfiers-for-chemicals-and-cookniu-
odors/products/breathesmart-air-punfier-
w-hepa-freshplus-
fi!ter?varlant=890004515
Amaircare
3000 HE PA Air
Purifier
Portable. Not ducted
Amaircare
Canada
http://amaircare.com/
Amaircare
7500 Airwash
Cart
Portable. Ductable or
freestanding.
Amaircare
Canada
http://amaircare.com/
Amaircare
AirWash 10000
Built in Ducted
Amaircare
Canada
http://wwwairpurifiersandcleaners.eom/a
maircare-10000-hvac-air-cleaner
-tv
¦VI

-------
00
Image
Brand
Name
Model
Installation Type
Manufacturer
Manufacture
Country
Website


x	_
m

Austin Air
Healthmate Plus
Portable. Not ducted
Austin Air
USA
http://austinair.com/



Blue Air
Pro XL
Portable. Not ducted
Blue Air

httos://www blueair.com/us




Coway
AP-1512HH
Mighty Air Purifier
Portable. Not ducted
Coway
Korea
httD://retail. cowav-usa.com/
m


K
¦J

Dyson
Pure Cool Link
Tower
Portable. Not ducted
Dyson
Malaysia
httD://www. dvson. com/

NEW
0
i
EverClear
DeluxCM-11
Built in. Not ducted.
Air Quality
Engineering

httD://www.air-aualitv-ena com/

-------
Image
Brand
Name
Model
Installation Type
Manufacturer
Manufacture
Country
Website

Fresh-Aire UV
APCO
Built in. Ducted
APCO
USA
httD://www.freshai reuv.com/aDco. html


Hammacher
Air Purifier





Schlemmer





/ HfiUMp
/ r w-
Honeywell
F111C1073W-3S

Air Pure Systems

httos://www.cleanairfacilitv.com/asD oaa
es/cataloa. asc?PCA= 10
	
Honeywell
F114C1008
commercial
Built in. Not ducted.
Honeywell

htto://www. honevwellstore.com/
It
//" '"///// /j-;r

ceiling mount




---
Honeywell
F115A1064
commercial
Built in. Not ducted.
Honeywell

httD://www. honevwellstore.com/
/?//
£ S

ceiling mount





Honeywell
F116A1120-3S
Commercial
Built in. Ductable or not
ducted.
Honeywell

httc://www. nonevwelistore.com/
*1Q

Duct able





Honeywell
F120A1023
Ducted
Built in. Not ducted.
Honeywell

htto://www. honevwellstore.com/
-fcv
-------
§
Image
Brand
Name
Model
Installation Type
Manufacturer
Manufacture
Country
Website



IAP
M-25DDCC
Built in. Not ducted.
Industrial Air
Purification
USA
httc://indust riaiairDurification.com/


a
Q
ty
0
J


IQAir
Clean Zone 5200
Portable. Ductable or
not ducted.
IQAir
Switzerland
httD://www.iaair.com/











~

IQAir
Clean Zone SL
Portable. Not ducted
IQAir
Switzerland
httD://www.ioair.com/
1
r
*
1
IQAir
GC/XVOC Air
Purifier
Portable. Not ducted
IQAir
Switzerland
http://www. iaair.com/acx-series-air-
Durifiers/tech-scecs

f
,
w
IQAir
GCX Multigas
Portable. Not ducted
IQAir
Switzerland
httD://www.iaair.com/acx-series-air-
Durifiers/tech-scecs

MaxFlo
MAXFLO D-25
Built in. Not ducted.
Diversified Air
Systems
USA
httD://maxfloair.com/Home.asDX
1














MaxFlo
MAXFLO D-30
Built in. Not ducted.
Diversified Air
Systems
USA
httD://maxfloair.com/Home.asDX
-------
Image
Brand
Name
Model
Installation Type
Manufacturer
Manufacture
Country
Website



NQ Clarifier
Air Purifier
Portable. Not ducted
NQ clarifier
USA
http://www. nainc.com/












RabbitAir
BiOGS 2.0-
625A
Portable. Not ducted
RabbitAir

httDs://www. rabbitair.com/7utm source=
bina&utm medium=CDC&utm camDaian=
Search% 20% 7C% 20US% 20% 7C% 20AL
PHA% 20% 7C% 20Brand8utm term=Rab
bitAir&utm content=Rabbit% 20Air
1


Sentry Air
Systems
SS-700-FH
Built in. Not ducted.
Sentry Air Systems
USA
httD://www.sent rvair.com/index. htm
T
tl
1111
ill
m -
lllllllllill
IIIIIMHI
«ll!l||l!!lillll|

Sun Pure
SP-20C
Portable. Not ducted
Field Controls

httD://www.fieidcontrols.com/sun-Dure
E
1

p

Temp Air
C2000
Portable. Ductable or
not ducted.
Temp air
Rentai
httD://temD-air.com/
-------
Image
Brand
Name
Model
Installation Type
Manufacturer
Manufacture
Country
Website

Trion
Air Boss ATS
Built in. Ducted
Trion
USA
httDs://www.trioniaa. com/i ndex. asox
'FT £






x"






¦
Winix
U450
Portable. Not ducted
Winix
USA
httDs://winixameri ca.com/
-------




Power
Noise
Image
Brand Name
Model
Voltage
Current
(amperes)
Decibels
(Maximum)
Decibels
(Minimum)
Noise
Measurement
Notes
\W\
Aerus
Sanctuairy by Aerus !n-
Duct Whoie House Air
Purifier
100-240V
0.4



/
Air Oasis
Large commercial
models
24VDC



No noise
measurements
recorded
_ ' ¦
Air Quality
Engineering
M66R&L
110-480
12-4.4
73-70

70 at 15 ft. 73 at 9 ft,
no minimum
measurement
%flB
Air Quality
Engineering
M73
208-480V



No noise
measurements

Airgle
AG950 PurePal Multigas
Air Purifier
110V

32


i
i£ 
-------




Power
Noise
Image
Brand Name
Model
Voltage
Current
(amperes)
Decibels
(Maximum)
Decibels
(Minimum)
Noise
Measurement
Notes
w
no
If"-'
Airpura
R600 All Purpose
115V or
220V
40- 120 watts
62.3
28.1
At distance of 6 ft.
pi -







rr
Alen
Breathesmart-HEPA-
FreshPlus
120 V

56
41.5

M
Amaircare
3000 HEPA Air Purifier
115V

57
33


Amaircare
7500 Airwash Cart
120 V

96
82

n -
\ "*88h'















-------
Image
Brand Name
Model
Voltage
Current
(amperes)
Decibels
(Maximum)
Noise
Decibels
(Minimum)
Noise
Measurement
Notes
Amaircare
Air Wash 10000
115V
75
75
Only one noise
measurement listed
Austin Air
Healthmate Plus
120V
65
<50
Unspecified minimum
noise measurement
Blue Air
Pro XL
33-256W
58
32

Coway
AP-1512HH Mighty Air
Purifier
53.8
24 4
Ol
Cn
-------
Ol
o>
Image
Brand Name
Model
Power
Voltage
Current
(amperes)
Decibels
(Maximum)
Noise
Decibels
(Minimum)
Noise
Measurement
Notes
TO
Ul
Dyson
Pure Cool Link Tower
EverClear
Delux CM-
115
4.3
No noise
measurements
r
Fresh-Aire UV
APCO
18-32 VAC
0.68
No noise
measurements
recorded
Hammacher
Schlemmer
Air Purifier
Honeywell
F111C1073W-3S
120
7.5
53
@ 3.3 feet
/!
Honeywell
F114C1008 commercial
ceiling mount
220-240V
17
59
55
Measured at 3.3 ft.
Honeywell
F115A1064 commercial
ceiling mount
220-240V
3.6
56
52
Measured at 3.3 ft.
-------
Ol
^sl



Power
Noise
Image
Brand Name
Model
Voltage
Current
(amperes)
Decibels
(Maximum)
Decibels
(Minimum)
Noise
Measurement
Notes

Honeywell
F116A1120-3S
Commercial Ductable
120-220
VAC
14-7


No noise
measurements
K»o>|


UP






recorded

Honeywell
F120A1023 Ducted
120-240V
2.8-7
52
48


IAP
M-25DDCC
115V
10.2
62

No minimum
measurement
~ 3
IQAir
Clean Zone 5200
220-240V

65
35
10 ft. measurement
Q 1 0







P P
t







11
IQAir
Clean zone SL
220-240V

45

10 ft. measurement,
no minimum
measurement
° I







-------
Ol
Co



Power
Noise
Image
Brand Name
Model
Voltage
Current
(amperes)
Decibels
(Maximum)
Decibels
(Minimum)
Noise
Measurement
Notes
f
IQAir
GC/XVOC Air Purifier
100-120V

69
35
Max sounds like
dishwasher, Min
sounds like a whisper
J A







T







"P
IQAir
GCX Multigas
100-120V

69
35
Max sounds iike
dishwasher. Min







sounds like a whisper
mm
V







1'







¦UBS"-"'""
MaxFlo
MAXFLO D-25
230V
11.2
63

No minimum







measurement

MaxFlo
MAXFLO D-30
115V
8.5
62

No minimum
measurement

NQ Clarifier
Air Purifier
115-230V

55

Minimum noise level
«*e=»"






not listed









RabbitAir
BiOGS 2.0-625A
120V

50.4
22.8

-------
Image
Brand Name
Model
Power
Voltage
Current
(amperes)
Decibels
(Maximum)
Noise
Decibels
(Minimum)
Noise
Measurement
Notes
O
"I
Sentry Air
Systems
SS-700-FH
115V
4.9
No minimum
measurement
Illilllllllllllllllllllf
llllllllllll
liiiiiiiiiiiiiiiiil
Sun Pure
SP-20C
120
48
%
Temp Air
C2000
115
15
No noise
measurements


Trion
Air Boss ATS
NA
No noise
measurements
Winix
U450
110W
56
29
Minimum noise level
not listed
Ol
to
-------
o>
o
Image
Brand Name
Model
Flow Rate
Flow Rate
Minimum
(cfm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Modes of Action
Filter Type Description
Adsorption
Aerus
Sanctuairy by Aerus In-
Duct Whole House Air
Purifier
3000 ft.2
Uses light waves and catalytic
process to remove pathogens, air
pollution, dust, dander, and odors.
(Photo catalysis and UV)

Air Oasis
Large commercial
models
60
120
5000
Bi-Polar Ionization 8 AHPCO
(advanced hydrated
photocatalytic oxidation)
technology that was developed by
NASA (ionization and UV
No
Air Quality
Engineering
M66 R8L
1940
3225
NA
30-35% efficient pleated filters,
HERA and electrostatic add-on
modules, 45 or 90 lbs. of
activated carbon
Yes
Air Quality
Engineering
M73
5500
NA
Two 24' x 24" x 4* pleated
prefilter, four 24" x 24" x 7 mist
impingers, two 24' x 24" x 12'
Polypropylene ESF, 180 lbs.
activated carbon
Yes
Airgle
AG950 PurePal Multigas
Air Purifier
268
463
max. 617
ft2
HEPA
Carbon -15 lbs. coconut shell
activated carbon with premium
quality activated alumina
Yes
<£ * H 9.
-------



Flow Rate
Modes of Action
Image
Brand Name
Model
Flow Rate
Minimum
(efm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Filter Type Description
Adsorption
B**=a
AirPura
C600DLX Air Purifier
560
560
2000 ft2
HEPA Prefilter
Carbon - 26 lbs. of granular
activated carbon
Yes
1	J







HP*1 v
Airpura
R600 All Purpose
440
440
up to
1650 sq
ft
Cleanable prefilter; 2 anti-
microbial filters; 18 lb. carbon
filter, 2" deep; True HEPA filter
(40 sq. ft of media w/10 pleats
per inch)
Yes








rT
Alen
Breathesmart-HEPA-
FreshPius
150
286
1100 ft2
HEPA air prefilter, electrostatic
HEPA materiai, 3 lbs. activated
carbon.
Yes
!J
Amaircare
3000 HEPA Air Purifier
50
225
about 800
ft2 @2
exchange
s per hr.
HEPA Prefilter
12 lbs. Activated Carbon; have
option for Carbon/ Zeolite filter
Yes

Amaircare
7500 Airwash Cart
1000
1000
about
3750 ft2 @
2
exchange
s per hr.
HEPA Prefilter
Carbon - 26 lbs. of granular
activated carbon; have option for
Carbon/ Zeolite filter
Yes
-------
o>
K)
y
Image
Brand Name
Model
Flow Rate
Modes of Action
Flow Rate
Minimum
(efm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Filter Type Description
Adsorption



Amaircare
Air Wash 10000
1980
1980
11250 ft2
Triple cylindrical perfect seal 3-
stage cartridges (each: 13"
diameterx16" height); stage one:
1/8" foam prefilter sleeve x3;
stage two: 100 sq. Ft. Pleated
easy twist HEPA cartridge x3;
stage three: %' non-woven
polyester filter media imbued
200% with activated carbon (164
g = 180,400 m2adsorption
surface area) x3; optional stage
three canister: Granulated carbon
pellets encased in steei mesh
canister (1550 g = 1,705,000 m2
adsorption surface area) x3
Yes

i


Austin Air
Heaithmate Pius
75
400
up to 875
ft2 @2
exchange
s per hr.
HEPA Prefilter
15 lbs. Activated Carbon / Zeolite
filter impregnated with potassium
iodide
Yes
l
Blue Air
Pro XL
800
950
1180
Activated carbon pellets and
thermally bonded fibers
containing polypropylene and
polyethylene free of chemicals
and binders.
Yes
-------
Image
Brand Name
Model
Flow Rate
Flow Rate
Minimum
(cfm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Modes of Action
Filter Type Description
Adsorption
Coway
AP-1512HH Mighty Air
Purifier
269
up to 326
ft2
HE PA prefilter
Carbon - 26 lbs. of granular
activated carbon
Yes
[T
Li
Dyson
Pure Cool Link Tower
190
190
unspecifie
d
HEPA prefilter
Carbon at unspecified quantity
Yes

EverClear
DeluxCM-1
400
NA
95% efficient (at .3 micron) HEPA
type filters, 44 lbs. of activated
carbon
Yes
Fresh-Aire UV
APCO
Combination of UV-C light and
activated carbon
Yes
Hammacher
Schlemmer
Air Purifier
up to 150
ft2
HEPA
Nano confined catalytic oxidation
No
Honeywell
F111C1073W-3S
1150
825
n/s
Model selected is for a 95%
ASHRAE particulate filter. HEPA
available in different modei
43 pounds of carbon,
permanganate (Note: equipment
catalog list zeolite also but
replacement filter page includes
only charcoal/permanganate).
Yes
o>
-------
2
Image
Brand Name
Model
Flow Rate
Flow Rate
Minimum
(cfm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Modes of Action
Filter Type Description
Adsorption
Honeywell
ll:
//-" W/////
F114C1008 commercial
ceiling mount
180
325
400
95% DOP (Di-octyl phthalate)
Efficient Filter at 0.3 Micron, 8+
lbs. CPZ Filter
Yes
Honeywell
F115A1064 commercial
ceiling mount
600
750
99.97% HERA Filter, 16+ lbs.
CPZ Filter
Yes
Honeywell
F116A1120-3S
Commercial Ductable
1400
1675
not listed
First stage is a prefilter rated 30-
40% ASHRAE dust spot
efficiency, second stage is a set
of 40 plus pounds of CPZ filters
(charcoal, permanganate,
potassium, and zeolite), The third
stage includes a set of CPZ filters
Yes
Honeywell
F120A1023 Ducted
900
1050
1200
95% DOP Efficient Filter at 0.3
Micron, 22+ lbs. CPZ Filters for
gas, odor, and volatile organic
compounds (VOC) control
Yes
^9
IAP
M-25DDCC
300
2500
NA
Pleated prefilter, 95% bag filter,
36 lb. charcoal canister filter
Yes
IQAir
Clean Zone 5200
600
HEPA filter, activated carbon
Yes
-------
o>
Oi



Flow Rate
Modes of Action
Image
Brand Name
Model
Flow Rate
Minimum
(efm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Filter Type Description
Adsorption

IQAir
Clean zoneSL

600

HEPA filter, activated carbon
Yes
~







1
IQAir
GC/XVOC Air Purifier
50
370
up to
1385 ft2 @
2 ex-
changes
per hr.
HEPA prefilter
Carbon -17 lbs. of granular
activated carbon
Yes
f.
V
IQAir
GCX Multigas
40
300
up to
1125 ft2 @
2 ex-
changes
per hr.
HEPA prefilter
Carbon -12 lbs. of granular
activated carbon & alumina
pellets impregnated with
potassium permanganate
Yes

MaxFlo
MAXFLO D-25

2500
NA
4" Pleated prefilter, 95% 36"
pocket filter, 2" charcoal filter
Yes
J ¦'
MaxFlo
MAXFLO D-30
1600
3000
NA
4" pleated prefilter, 22" 95%
pocket filter, 2" charcoal filter
Yes

NQ Clarifier
Air Purifier
350
350
up to
1310ft2 @
2 ex-
changes
per hr
HEPA
Carbon -15 lbs. of granuiar
activated carbon with patented
oxidizing media
UV
Yes
\ -Bg
X>^^0







-------
o>
o>
Image
Brand Name
Model
Flow Rate
Flow Rate
Minimum
(cfm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Modes of Action
Filter Type Description
Adsorption
RabbitAir
BIOGS 2.0-625A
42
167
up to 625
ft2
HERA Prefilter
Carbon - <1 lb. of granular
activated carbon in filter
Yes
* *
Sentry Air
Systems
SS-700-FH
600
NA
MtRV pre-and post-filter, 16 lbs
activated carbon
Yes
i lP||!|UH||i||||i||||j!l|||!
¦ tilliilliliminiillililllimi!
Ill
1111 lllllHli
iiif
Sun Pure
SP-20C
265
265
2,000 sq.
feet max.
.3 micron HERA / 5.0 micron
prefilter
Photo-catalytic purification with
metal oxides, activated charcoal
Yes
Temp Air
C2000
1600
2000
NA
HEPA, activated carbon
Yes
MS.
'I
Trion
Air Boss ATS
1285
10385
NA
HEPA, activated carbon
Yes
-------



Flow Rate
Modes of Action
Image
Brand Name
Model
Flow Rate
Minimum
(cfm)
Flow Rate
Maximum
(cfm)
Listed
Room
Size
Filter Type Description
Adsorption

Winix
U450
78
300
up to 450
ft2
HEPA Prefilter
Activated carbon filter
Yes
1	







o>
VI
-------
OS
CO
Image
Brand Name
Model
Modes of Action
Pounds
of
Carbon
Oxidation
Negative
Ionization
Photo-
Catalytic
Purification
Other
(describe)
Modes of
Action Notes
Aerus
Sanctuairy by Aerus In-Duct Whole
House Air Purifier
Yes
Air Oasis
Large commercial models
Yes
UV
Air Quality
Engineering
M66R&L
90
Yes
electrostatic
purification
40 or 90 lbs.
carbon
Air Quality
Engineering
M73
180
impingers,
ESF
Airgle
AG950 PurePal Multigas Air
Purifier
15
Yes
activated
alumina

AirPura
C600DLX Air Purifier
26
-------
Image
Brand Name
Model
Modes of Action
Pounds
of
Carbon
Oxidation
Negative
Ionization
Photo-
Catalytic
Purification
Other
(describe)
Modes of
Action Notes
Airpura
R600 All Purpose
18
No
No
No
Activated
coconut shell
carbon
Alen
Breathesmart-HEPA-FreshPlus
E?
Yes
Amaircare
3000 HEPA Air Purifier
12
Amaircare
7500 Airwash Cart
26
Amaircare
Air Wash 10000
3.78
HEPA
-------
3
Image
Biand Name
Model
Modes of Action
Pounds
of
Carbon
Oxidation
Negative
Ionization
Photo-
Catalytic
Purification
Other
(describe)
Modes of
Action Notes


K
%


Austin Air
Healthmate Plus
15
Yes







Blue Air
Pro XL


Yes







Coway
AP-1512HH Mighty Air Purifier
26

Yes




i
iJ

Dyson
Pure Cool Link Tower







NEW

0

EverClear
DeluxCM-11
44



HEPA

-------
Image
Brand Name
Model
Modes of Action
Pounds
of
Carbon
Oxidation
Negative
Ionization
Photo-
Catalytic
Purification
Other
(describe)
Modes of
Action Notes
-
Fresh-Aire UV
APCO
UV
Hammacher
Schlemmer
Air Purifier
Yes
Honeywell
F111C1073W-3S
43
Yes
//•
Honeywell
F114C1008 commercial ceiling
mount
8+lbs. ofCPZ
f#//
Honeywell
F115A1064 commercial ceiling
mount
16
16+ lbs. ofCPZ
Honeywell
1-116A1120-3S Commercial
Duct able
40
Yes
40 lbs. ofCPZ
(carbon,
permanganate,
potassium,
zeolite)
Honeywell
F120A1023 Ducted
22
22+ lbs. ofCPZ
-------
3
Image
Brand Name
Model
Modes of Action
Pounds
of
Carbon
Oxidation
Negative
Ionization
Photo-
Catalytic
Purification
Other
(describe)
Modes of
Action Notes
•9
iAP
M-25DDCC
36
bag filter
IQAir
Clean Zone 5200
IQAir
Clean zone SL
r.
IQAir
GC/X VOC Air Purifier
17
No
n.
IQAir
GCX Multigas
12
Yes
MaxFlo
MAXFLO D-25
2" charcoal
filter
-------
Image
Brand Name
Model
Modes of Action
Pounds
of
Carbon
Oxidation
Negative
Ionization
Photo-
Catalytic
Purification
Other
(describe)
Modes of
Action
Notes
MaxFlo
MAXFLO D-30
2" charcoal
filter
NQ Clarifier
Air Purifier
15
Yes
UV
RabbitAir
BIOGS 2.0-625A
No
* '
Sentry Air
Systems
SS-700-FH
16
Sun Pure
SP-20C
Yes
iilliiillliiiii iiili 'illlllllillll
liliiiiiiiiiiiiiii
Temp Air
C2000
HEPA
2
-------



Modes of Action
Image
Brand Name
Model
Pounds
of
Carbon
Oxidation
Negative
Ionization
Photo-
Catalytic
Purification
Other
(describe)
Modes of
Action Notes

Trion
Air Boss ATS




HEPA










.

















1	
Winix
U450

No




-------
Image
Brand Name
Model
Listed
filter
life
span
Cost ($US)
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement Filter
Cost Information
Source
Aerus
Sanctuairy
by Aerus In-
Dud Whole
House Air
Purifier
$1,700
http://www.allerav
buversdub.com/s
anduairv-bv-
aerus-in-duct-
whole-house-air-
punfiers.html
Air Oasis
Large
commercial
models
not
specified
not
specified
Must
contact
supplier for
price of unit
$150
http://www.airoasis.c
om/produd-
categorv/commercial/
commercial-
replacement-parts
Air Quality
Engineering
M66 R&L
Na
Prices not
iisted,
contact
manu-
facturer for
details

Air Quality
Engineering
M73
NA
Prices not
listed,
contact
manu-
facturer for
details
Airgle
AG950
PurePal
Multigas Air
Purifier
12-16
months
12-16
months
$1,800
Approx.
cost for
replacement
filter
http://www.airgle
com/PurePaiClea
nRoom I
$200
(£) 6 ® fit
5!
-------



Listed
Cost ($US)
Image
Brand Name
Model
filter
life
span
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement Filter
Cost Information
Source
fff0 |
AirPura
C600 DLX
1 year
$849.98

httD://www.allerav
$ 59.98
$ 249.98
htto://www alleravbu


Air Purifier
2 years


buversclub.com/a
iroura-r600-air-
Durifiers.html?ite
mld=3012


versclub.com/airoura
-r600-air-
purifiers. html?itemld
=3012
* •'









¦p* - i
¦— -
M: '
Airpura
R600 All
Purpose
2 years
$749.98
On sale
$649.98
httD://www.allerav
buversclub.com/a
iroura- r600-air-
Durifiers.html?ite
mld=3012
$169.98
$199.98
htio://www.alleravbu
versclub.com/airoura
-r600-air-
ourifiers. html?itemld
=3012
H?
A!en
Breathe-
smart-
HEPA-
F'reshPlus
8-9
months
$658

https://www.al enc
oro.com/collectio
ns/air-ourifiers-
for-chemicals-
and-cookina-
odors/Droducts/br
eathesmart-air-
Durifier-w-heoa-
fresholus-
filter?variant=890
004515

$119
httDs://www alencoro
.com/collections/aien
-breathesmart-fit50-
heoa-fresholus-
reolacement-
filters/oroducts/alen-
breathesmart-fit50-
heoa-fresholus-filter
H
Amaircare
3000HEPA
Air Purifier
2-5
years
1 year
$799
Tyr
Phone
$219
$199
Phone
-------




Listed
Cost ($(JS)
Image
Brand Name
Model
filter
life
span
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement Filter
Cost Information
Source
leien 1
AirPura
C600 DLX
1 year
$849.98

httc://www allerav
$59.98
$249.98
httD://w'«w.alleravbu


Air Purifier
2 years


buversclub.com/a
iroura-r600-air-
Durifiers.html?ite
mid=3012


versclub.com/airDura
-r600-air-
ourifiers. html?itemld
=3012










r i
1. -Ntwash'
kv
Amaircare
7500
Airwash Cart
2-5
years
6-12
months
$3,699
3-5 y rs.,
contains 2
HEPA
filters
Phone
$219
$199
Phone
Ij
Amaircare
Air Wash
10000
Prefilter:
1 yr.;
HEPA:
3-5 y rs.;
Carbon:
6 months
$4,000
Replace-
ment filter
costs not
found
httD://www.airpurif
iersandcleaners.c
om/amaircare-
10000-hvac-air-
cleaner




Austin Air
Healthmate
Plus
3-5
years
$649
Did not
specify cost
of HEPA
prefilter
htto://austinair.co
m/healthmate-2/

$325
http://austinair.eom/h
ealtnmate-2/










-Nl
-------
3





Listed
Cost ($US)
Image
Brand Name
Model
filter
life
span
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement Filter
Cost Information
Source
i


Blue Ail
Pro XL
6 months
$2,500

httDs://'www.bluea
ir.com/us/air-
purifiers/pro-xl

$360
nttDs://www.biueair.c
om/us/% E2% 80% 8B
% E2%80% 8Bair-
Durifier-filters/oro-xl-
smokestoc

Coway
AP-1512HH
1 year
$300
no replace-
http://www allerav



i
$

Mighty Air
Purifier
6 months

ment filter
costs found
buversclub.com/c
owav-miahtv-air-
Durifiers.html



p
l
1

Dyson
Pure Cool
Link Tower
Too new
to tell but
claim
sensor
$500










you
know






NEW


EverClear
DeluxCM-
11
NA

Prices not
listed,
contact
manu-









facturer for
details





Fresh-Aire UV
APCO
Lifetime

Prices not
listed





|






-------



Listed
Cost ($US)
Image
Brand Name
Model
filter
life
span
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement Filter
Cost Information
Source

Hammacher
Schlemmer
Air Purifier
3 years
$149





r>
Honeywell
F111C1073
W-3S
N/S
$2,690
Particulate
filter price
includes
prefilter
cost.
VOC
replace-
ment filter
cost is for 2
(required)
filters.
httcs://www.clean
airfacilitv.com/asD
caaes/cataloa.a
sd?PCA=10
$260
$610
httDs://www.cleanairf
acilitv.com/asc Daae
s/cataloa.asD?PCA=
34

Honeywell
F114C1008
<30
$1,500
Price of
httc://www.honev
$35

httD://www.honevwell
ft:.
f/JJ W///// /jf
commercial
ceiling
mount
months
VOC filters
not listed
wellstore.com/sto
re/croducts/honev
well-f114c1008-
commercial-
ceilina-mount-
media-air-
cleaner.htm


store.com/store/catal
oa.asD?item=8917
/r
Honeywell
F115A1064
commercial
ceiling
mount

$1,860
Price of
VOC filters
not listed
httD://www.honev
wellstore.com/sto
re/croducts/honev
well-f115a1064-
media-air-
cleaner-with-
heca-filter-and-
Drefilter.htm
$35

httD://www.honevwell
store.com/store/catal
oa.asD?item=8918
2
-------



Listed
Cost ($US)
Image
Brand Name
Model
filter
life
span
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement Filter
Cost Information
Source

Honeywell
F116A1120-
3S
Commercial
Ductable
Unspecifi
ed
$3,300
Price of
VOC filters
not listed

$200



wellstore.com/Dro
ducts/honevwell-
f116a1120-
ductable-or-
stand-alone-
three-staae-
media-air-
cleaner.htm

store.com/store/Drod
ucts/honevwell-
32000196-media-
filter-for-model-f116-
95-ashrae. htm
,
Honeywell
F120A1023
Ducted
unspecifi
ed
$2,650
Price of
VOC filters
not listed
httD://www.honev
wellstore.com/sto
re/croducts/honev
well-fl 20a1023-
$69

htio://www. honevwell
store.com/store/Drod
ucts/oref i Iter-for-
commercial-air-






ducted-stand-
alone-media-air-
cleaner.htm


cleaner-for-f120a-12-
oack-32003983-
001.htm
*11
IAP
M-25DDCC
not listed
$3,192
Filter prices
not listed
htto://indust rialair
purification.com/a
mbient-air-
cleaners/m-25-
ambient-air-
cleaners-
2500cfm.html



~ 2
IQAir
Clean Zone
5200
NA

Would not
provide
with price




Q | 0
1 Y









-------
Image
Brand Name
Model
Listed
filter
life
span
Cost ($US)
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement Filter
Cost Information
Source
IQAir
Clean zone
SL
NA
Would not
provide
with price
r*
IQAir
GC/XVOC
Air Purifier
18 mos.
2-4 yrs.
$2,199
httpV/www.iaair.c
om/gcx-series-air-
purifiers/buv
139/HEPA
prefiiter
169/postfi Iter
sleeves (4
count)
495/GCX
cartridge
(4count)
http://wvw.iaaii.com/
commerciai/support/r
eplacementfi Iters

IQAir
GCX
Multigas
1 yr.
2.5 yrs.
$2,199
http://www igair.c
om/acx-series-air-
purifiers/buv
139/HEPA
prefiiter
169/postfi Iter
sleeves (4
count)
495/GCX
cartridge
(4count)
http://www.iaair.com/
commercial/support/r
eplacementfi Iters
MaxFlo
MAXFLO D-
25
NA
Prices not
listed,
contact
manu-
facturer for
details
http://maxfloair.co
m/Products/AirCI
eaners.aspx
MaxFlo
MAXFLO D-
30
NA
Prices not
listed,
contact
manu-
facturer for
details
http://maxfloair.co
m/Products/AlrCI
eaners.aspx
Co
-------
00
KO



Listed
filter
life
span
Cost ($US)
Image
Brand Name
Model
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement
Filter Cost
Information
Source

Hammacher
Schlemmer
Air Purifier
3 years
$149





& >
Honeywell
F111C1073
W-3S
N/S
$2,690
Particulate
filter price
includes
prefilter
cost.
VOC
replacemen
t filter cost
is for 2
(required)
filters.
httcs://www.clean
airfacilitv.com/asD
caaes/cataloa.a
sd?PCA=10
$260
$610
httDs://www.cleana
irfacilitv.com/asD
Daaes/cataloa.asD
?PCA=34
J/'.
/V ////„/, //(y
Honeywell
F114C1008
commercial
ceiling
mount
<30
months
$1,500
Price of
VOC filters
not listed
httc://www. honev
wellstore.com/sto
re/croducts/honev
well-f114c1008-
commercial-
ceilina-mount-
media-air-
cleaner.htm
$35

httD://www. honevw
ellstore.com/store/
cataloa.asD?item=
8917
1
i
Honeywell
F115A1064
commercial
ceiling
mount

$1,860
Price of
VOC filters
not listed
httc://www. honev
wellstore.com/sto
re/croducts/honev
well-f115a1064-
media-air-
cleaner-with-
heca-filter-and-
Drefilter.htm
$35

httD://www. honevw
ellstore.com/store/
cataloa.asD?item=
8918
-------
Image
Brand Name
Model
Listed
filter
life
span
Cost ($US)
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement
Filter Cost
Information
Source
NQ Clarifier
Air Purifier
2-3
years
1-2
years
$730
RabbitAir
BiOGS 2.0-
625A
1.5-3
years
$370
https://www rabbit
air.com/prociucts/
bioas2-air-purifier
$30
https://www. rabbit
air.com/product s/b
logs2-ac-charcoal-
filter

Sentry Air
Systems
SS-700-FH
NA
Prices not
listed,
contact
manu-
facturer for
details
http.//www.sentrv
air.com/specs/am
bient-air-filtration-
system .htm
Sun Pure
SP-20C
2 years
MUlllllllllilllllllllillllllliflll
t IHlllll		 lllll llllllllllllll
' hiiiiiiiiiiiih i i iiiiii niiim
Willi® "IllIIIIlI
¦llllllllllllll'lllllllllfl
http://www.fieldco
ntrols.com/sun-
Piire-3-in-1-air-
curlfication-
svstem?page id=
185
http://www.fieldcon
trols.com/sun-
pure-3-in-1-air-
purification-
svstem?page id=
185
ir-T) I
Temp Air
C2000
NA
Rental
This unit is
a rental
Co
CO
-------



Listed
filter
life
span
Cost ($US)
Image
Brand Name
Model
Equipment
Price
Cost Notes
Equipment Price
Source
Replacement
Particulate
Filter Price
Replacement
VOC Filter
Price
Replacement
Filter Cost
Information
Source
J
Trion
Air Boss
ATS
NA

Prices not
listed,
contact
manu-
facturer for
details




1
VVinix
U450
12
months,
wash-
able at 3
months
$440
VOC filter
and HEPA
filter come
in 1 unit


$140
https://w!nixameric
a.com/Droduct/filte
r-f-114290/










-------
Image
Brand Name
Model
VOCs Tested For
VOCs tested for
Notes
TCE
PCE
1,1-DCA
Vinyl
chloride

m

Aerus
Sanctuairy by Aerus
In-Duct Whole House
Air Purifier






i—
- m
J

Air Oasis
Large commercial
models
Unspecified VOCs
Reduces carbon-based
contaminants and
provides the space with
fresh, clean air within
minutes. Carbon-based
contaminants are natural
impurities like bacteria,
mold, viruses, foul odors,
and volatile organic
compounds (VOCs).





, ' ¦

Air Quality
Engineering
M66R&L
Unspecified VOCs
Fine dusts, smoke, soot,
vapors, mist, VOCs






s
m
p|

Air Quality
Engineering
M73
Unspecified VOCs
Smoke, mist, dust and
other airborne
contaminants




j
uD
I
**
n

Airgle
AG950 PurePal
Multigas Air Purifier
Benzene, toluene, and
xylene, as well as
cooking gas, paint and
building material
vapors, and tobacco
smoke
Residential




Co
Oi
-------
00
o>



VOCs Tested For
Image
Brand Name
Model
VOCs tested for
Notes
TCE
PCE
1,1-DCA
Vinyl
chloride
h—J
AirPura
C600 DLX Air Purifier
Tobacco smoke,
perfumes, vehicle
emissions, off gassing
from new flooring,
cleaning chemical
vapors, formaldehyde,
benzene, toluene,
ammonias, and other
VOCs, nitrous dioxide,
nitrous trioxide,
monoethylamine,
hydrogen sulfide,
mercury vapors,
chlorine dioxide,
hydrogen bromide,
sulfur dioxide, hydrogen
fluoride, hydrogen
chloride, methylene
chloride, radioactive
iodine, naphthene,
pesticides, chlorine
Residential




Wi. 1 v
— -
*- —
Airpura
R600 Aii Purpose















cr
Alen
Breathesmart-HEPA-
FreshPlus
Unspecified VOGs
Large particles, dust,
pollen, pet dander, mold
spores, odors, VOCs,
smoke




-------
Image
Brand Name
Model
VOCs Tested For
VOCs tested for
1,1-DCA
Vinyl
chloride
Amaircare
3000 HERA Air
Purifier
Unspecified VOCs
Residential
Amaircare
7500 Airwash Cart
Unspecified VOCs
Commercial use
Amaircare
AirWash 10000
Unspecified VOCs
Biologicals, particulate
and VOCs
-------
00
00
Image
Brand Name
Model
VOCs Tested For
VOCs tested for
Notes
1,1-DCA
Vinyl
chloride
Blue Air
Pro XL
Unspecified VOCs
Large particles, dust,
pollen, pet dander, mold
spores, odors, VOCs,
smoke
Coway
AP-1512HH Mighty
Air Purifier
Unspecified VOCs
Residential
N
U
Dyson
Pure Cool Link Tower
A layer of activated
carbon granules
eliminates odors and
potentially harmful
toxins such as paint
fumes. No specified
VOCs
Residential
EverClear
DeluxCM-1
Unspecified VOCs
Odors, tobacco smoke,
pollen, dust, vapors and
many other irritants.
Fresh-Aire UV
APCO
Unspecified VOCs
-------
Image
Brand Name
Model
VOCs Tested For
VOCs tested for
1,1-DCA
Vinyl
chloride
Hammacher
Schlemmer
Air Purifier
Unspecified VOCs
A numeric display
indicates the level of
VOCs present and
continues to count
down as the air purifier
removes them
Residential
Honeywell
F111C1073W-3S
Honeywell
//¦
/!¦'
F114C1008
commercial ceiling
mount
Unspecified VOCs
8+ lbs. CPZ Filters for gas,
odor and volatile organic
compounds (VOC) control.
Honeywell
F115A1064
commercial ceiling
mount
Unspecified VOCs
16+ lbs. CPZ Filters for
gas, odor, and volatile
organic compounds (VOC)
control.
Honeywell
F116A1120-3S
Commercial Ductable
Unspecified VOCs
Honeywell
F120A1023 Ducted
Unspecified VOCs
22+ lbs. CPZ Filters for
gas, odor, and volatile
organic compounds (VOC)
control.
CO
to
-------

IQAir
Clean zone SL
Unspecified VOCs
IQAir
GC/XVOC Air
Purifier
Benzene, butane,
carbon tetrachloride,
chlorine, chloroform,
chloropicrin,
cyclohexane, 1.1
Dichloroethane,
ethylene oxide, Freon
IS, indole, methyl
chloride, methyl
chloroform, methylene
chloride, nitrobenzene,
phosgene, pyridine,
sulfuric acid, toluene,
xylene.
commercial use
-------



VOCs Tested For
Image
Brand Name
Model
VOCs tested for
Notes
TCE
PCE
1,1-DCA
Vinyl
chloride
m
V
IQAir
GCX Multigas
Acetic acid, acetone,
acrolein, aerylonitrile,
1.3 butadiene, butyric
acid, carbon disulfide,
chlorine dioxide, cresol,
cyclohexanone,
Diethylamine,
dimethylamine, ethanol,
ethyl acetate, ethyl
acrylate, ethylamine,
formic acid, hydrogen
chloride, isoprene,
isopropanol, methanol,
methyl acrylate, methyl
disulfide, methyl ethyl
ketone, methyl
mercaptan, methyl
sulfide, methyl vinyl
ketone, methylamine,
nitroglycerine, ozone,
phenol, Skatole,
styrene, sulfur trioxide,
trichloroethyiene, tri
hylamine,
trimethylamine, vinyl
chloride
Highly recommended
variety
Residential use
Y
Y
Y


MaxFlo
MAXFLO D-25
Unspecified VOCs
Best for welding smoke,
grinding dust, sanding
dust, oil smoke, coolant
mist, powders, odors, etc.





MaxFlo
MAXFLO D-30
Unspecified VOCs
Best for welding smoke,
grinding dust, sanding
dust, oil smoke, coolant
mist, powders, odors, etc.




-------
to
Isj
Image
Brand Name
Model
VOCs Tested For
VOCs tested for
1,1-DCA
Vinyl
chloride
NQ Clarifier
Air Purifier
Unspecified VOCs
Commerciai use
_
RabbitAir
BIOGS 2.0- 625A
Unspecified VOCs
Residential
* '
Sentry Air
Systems
SS-700-FH
Unspecified VOCs
Solvent fume control,
pharmacy pill dust,
secondary clean room
scrubber, shop fumes
Sun Pure
SP-20C
¦III
llllllllllllll
"HIIII" I1'
Carbon monoxide,
pesticides, hair spray,
alcohols, tobacco
smoke, ammonia, paint
solvents, chlorinated
solvents, nitrous oxide,
cleaning chemicals,
ozone + smog
VOCs tested for not listed
Temp Air
C2000
Unspecified VOCs
-------
Image
Brand Name
Model
VOCs Tested For
VOCs tested for
Notes
TCE
PCE
1,1-DCA
Vinyl
chloride

' P-» *1 ^
J
xl

Trion
Air Boss ATS
Unspecified VOCs
Smoke, fumes, and
oil/coolant mists, nuisance
odors





1	

Winix
U450
Not published
Residential





-------

Image
Brand Name
Model
VOCs Tested For
Others
General Notes
Aerus
Sanctuairy by Aerus
In-Duct Whole House
Air Purifier
—Tfe jl
Air Oasis
Large commercial
models
Air Quality
Engineering
M66 R&L
This company used to be the supplier and manufacturer
for Honeywell industrial air cleaners untii they decided to
start making their own. There are a huge range of add-
ons, configurations, and motor types for this specific
model, for details see http://www.air-quality-
eng.com/specs/m66-media-air-filtration-systems/ or
http://www breathepureair.com/aqe_m66.html
Air Quality
Engineering
M73
There are a huge range of add-ons, configurations, and
motor types for this specific model, for details see
http.//www. air-aualitv-eng.com/specs/m73-industrial-air-
filterI or http://www.breathepureair.com/aae m73.html
Airgle
AG950 PurePal
Multigas Air Purifier
£ * a a
AG950 PurePal Multigas Air Purifier discontinued, AG900
PurePal Ciean Room closest model found
-------
Image
Brand Name
Model
VOCs Tested For
Others
General Notes
AirPura
C600DLX Air Purifier
-----
Airpura
R600 All Purpose
Alen
rf
Breathesmart-HEPA-
FreshPlus
Amaircare
3000 HEPA Air
Purifier
Amaircare
7500 Airwash Cart
(o
Ol
-------


Image
Brand Name
Model
VOCs Tested For
Others
General Notes
Amaircare
Air Wash 10000
This model not listed on official Website
Austin Air
Healthmate Plus
Blue Air
Pro XL
Coway
AP-1512HH Mighty
Air Purifier
Unclear where the amount of GAC was found, as unit
only weighs 15 lbs.
-------
Image
Brand Name
Model
VOCs Tested For
Others
General Notes

[1.
1
[
!
Dyson
Pure Cool Link Tower

Minimal data about what contaminants were tested, noise
output and power requirement

NEW

Everclear
DeluxCM-11

There are a huge range of add-ons, configurations, and
motor types for this specific model, for details see
htto://www. air-aualitv-ena.com/Droducts/everclear-cm-11-
commercial-air-cleaner/





Fresh-Aire UV
APCO

Not much information available


r



Hammacher
Schlemmer
Air Purifier



// >

Honeywell
F111C1073W-3S


//
W """"
Honeywell
F114C1008
commercial ceiling
mount


i
i
Honeywell
F115A1064
commercial ceiling
mount



I
0
D

Honeywell
F116A1120-3S
Commercial Ductable

Essentially you can mix and match this unit with different
types of filters to fit your needs, the specs listed are with
two CPZ filters. Can create a positive or negative
pressure gradient
-------






IQAir
Clean zone SL


~





IQAir
GC/XVOC Air
Purifier


\ v




-------
Image
Brand Name
Model
VOCs Tested For
General Notes
Others
t-
V
IQAir
GCX Multigas
Acetic acid, acetone, acrolein,
acrylonitrile, 1.3 butadiene, butyric acid,
carbon disulfide, chlorine dioxide, cresol,
cyclohexanone, Diethylamine,
dimethylamine, ethanol, ethyl acetate,
ethyl acrylate, ethylamine, formic acid,
hydrogen chloride, isoprene, isopropanol,
methanol, methyl acrylate, methyl
disulfide, methyl ethyl ketone, methyl
mercaptan, methyl sulfide, methyl vinyl
ketone, methylamine, nitroglycerine,
ozone, phenol, Skatole, styrene, sulfur
trioxide, tri hylamine, trimethylamine


MaxFlo
MAXFLO D-25

Charcoal filter can be interchanged with HERA filter
pp
MaxFlo
MAXFLO D-30



NQ Clarifier
Air Purifier


*r





RabbitAir
BIOGS 2.0- 625A


-------
o
o
Image
Brand Name
Model
VOCs Tested For
Others
General Notes

Sentry Air
Systems
SS-700-FH

Sun Pure
SP-20C
llllllllllll

Illiiillilli
Ililllllilllilll
"llllllllll
'i 1 f1 'III i"ll
llllllllllll
''lliillltlllilli

llll! III! Illlll)
Temp Air
C2000
Rental unit that uses carbon for various applications
Trion
Air Boss ATS
llf ^
Winix
U450
-------
ATTACHMENTB
AIR CLEANER EQUIPMENT
Adsorption-based Treatment Systems

101
-------
o
Manufacturer
Filtration Group
Filtration Group
Filtration Group
Website
www.fi It rationarouo.com
www.filtrationarouD.com
www.filtrationarouD.com




Image

mm
tjfccMs
ti
P
Brand Name
Filtration Group
Filtration Group
Aerostar
Model
Series 750 Carbon Pleat
Series 550 Carbon Pleat
HEGA filters: Grade 653 for VOCs.
Height (in.)
24
24
24
Width (in.)
24
24
24
Depth (in.)
2
2
12
Dimension Notes
many sizes
many sizes
many sizes include 2", 4", 12" deep
Weight (Pounds)


depends on size
Description
Carbon pleated filters that provide particle and
gas-phase filtration. Self-supportive media of
100% synthetic pre-filtration layer laminated to a
chemically enhanced activated carbon filtration
layer MERV11 for particles.
Carbon pleated filters designed for control of
intermittent odors and common indoor air
pollutants.
Specifications
•	500 g/m2 media loading
•	High Activity Carbon (85% CTC) Gas-phase
units allow choice of sorbent (Series 653 is
carbon), frames, and dimensions
•	Works on physisorption and catalysis
Listed filter life
span



Price
$125
$25
$490
Price Source
htto://www. filtrationarouD.com/WFS/FGCBusines
s/en US/-/USD/HVAC/hvac-Dieated-air-
filters/hvac-Dleated-air-filters-series-750-carbon-
Dleat-4/PLEAT-24x24x4-Nominal-Size-24-in-x-
24-in-x-4-in~zid173444
httD://www. filtrationarouD.com/WFS/FGCBusiness
/en US/-/USD/HVAC/hvac-Dieated-air-
filters/hvac-Dleated-air-filters-series-550-carbon-
Dleat-1/PLEAT-24x24x1-Nominal-Size-24-in-x-24-
in-x-1-in-zid15842
httD://www.fi ltrationarouD.com/WFS/FGCBusiness
/en US/-/USD/HVAC/hvac-aas-Dhase-filters/hvac-
aas-ohase-fi Iters-heaa-3653-seri es/HEGA-3653-
SERIES-Nominal-Size-24-in-x-24-in-x-12-in—
zid17982
Price Notes
Price depends on size and quantity
Price depends on size and quantity
Price depends on size and type of frame
-------
Manufacturer
Filtration Group
Dafco Filtration Group
AAF Intl.
Website
www.fiitrationarouD.com
dafcofiltrationarouc.com
aafintl.com






image




mm
Mi
Brand Name
Aerostar
Aerostar
AAF
Model
FP Gas-phase Filter
Side Access
Carbon Sorb Housing
AmAir/C family of filters
Height (in.)
24

24
Width (in.)
24

24
Depth (in.)
12

2
Dimension Notes
many sizes
from 0.5x0.5to 2.5x5 ft. cross section, various
depths
many sizes avail; 1", 2", 4" depths
Weight (Pounds)
24 for carbon; 28 for blend (media only)


Description
removes wide range of odors and
common indoor air pollutants at high
airflows. Constructed of heavy-duty
galvanized steel and plastic, with 3/4"
honeycomb media packs. Blend of 60% CTC
activated carbon and potassium permanganate
on zeolite is recommended for TCE; carbon
version for PCE.
This is a filter housing. Holds 2" or 4" pleated
prefilters and 3/4" refillable carbon trays.
Recommends 12 trays per 24" of height to
achieve low-pressure drop. Standard housing
depth is 36" for 2" prefilters and 38" for 4"
prefilters; other depths are available upon
request. Various sorbents available (carbon,
PPIS, blends)
Directly interchangeable with standard air filters.
Options; panels, pads, and 1", 2", and 4" pleated
filters, long-lasting gas-phase and particle filters,
with AAF's SAAFWeb™ technology chemical
media. High chemical media density yields
superior odor control. Carbon version more
recommended for chlorinated hydrocarbons.
Listed filter life
span



Price



Price Source



Price Notes



§
-------
o
Manufacturer
AAF Intl.
3M
Accumuiair
Website
aafintl.com
httD://www.filtrete.com/3M/en US/filtrete/croducts
www accumulair.com





saga
1H

	
Image

M

mm
Brand Name
AAF
i-iltrete
Accumuiair
Model
VariCel RF/C
Allergen Defense Odor Reduction Filter
Carbon
Height (in.)
24
20
20
Width (in.)
24
25
25
Depth (in.)
11.5
1
6
Dimension Notes
many sizes
many sizes, intended for residences
many sizes
Weight (Pounds)
7.8
1.3

Description
60% granular activated carbon; high-efficiency
removal of multiple contaminants. The media is
pleated and housed in a rigid metal frame. The
frame is available in either the standard box
style, no-header version, or with a single 13/16"
thick header.
Lightly pleated particle and gas filter, MERV 11,
activated carbon
Carbon-impregnated disposable pleated panel
filter
Listed filter life
span

up to 3 months
up to 3 months
Price

$10
$30
Price Source

httDs://wwwamazon.com/dD/B006EI5V70/ref=twi
ster B0004TYSUG? encodina=UTF8&Dsc=1
httDs://iet.com/Droduct/detail/3fb52c1e5d6846d7b
6136935c98e4994?icmD=Dla:aal:aen hardware a
2: heatina ventilation air oonditionina a2 other: n
a:PLA 348828540 24713608260 pla-
161719582140: na:na: na:28code=PLA15&ds c=a



en hardware a2&ds cid=&ds aa=neatina ventii
ation air conditionina a2 other&oroduct !d=3fb5
2c1 e5d6846d7b6136935c98e4994&Droduct oartit
ion id=161719582140&aclid=CN vlenEi84CFQM
LaQod9bsFla8aclsrc=aw.ds
Price Notes



-------
Manufacturer
Cameron Great Lakes
Purafi!
Clarcor
Website
httD://www calcarbon. com/
httDs://www.Durafil.com/
httoV/www.clcair.com/Brands-
Products/Airauard/HVAC/Gas-Phase


	IT	




Image

jf

m

M







Brand Name
CGL
Purafil
Airguard
Model
many
Puragrid
Vari-Klean
Height (in.)



Width (in.)



Depth (in.)



Dimension Notes
many sizes
many sizes
many sizes
Weight (Pounds)



Description
Many types from honeycombs to V-cells, to zig-
zag trays and more
Different sorbent and blends available
Pleated, different sorbents available, intended for
use for <500 ppb sites. Other products available
Listed filter life






span






Price



Price Source



Price Notes



-Jk
0
01
-------
o
o>

Manufacturer
Clarcor
Website
httD://www.clcair.com/B rands-
Product s/Airauard/HVAC/Gas-Phase
Image

mm
1111
rf?
Brand Name
Clarcor
Model
Carbon filter housings with refillable or
replacement trays
Height (in.)

Width (in.)

Depth (in.)

Dimension Notes
Various sizes
Weight (Pounds)

Description
Different sorbents and differing weights up to 90
pounds for the AG-2000
Listed filter life
span

Price

Price Source

Price Notes

-------
PRESORTED STANDARD
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
United States
Environmental Protection
Agency
Office of Research and Development
National Risk Management
Research Laboratory
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
EPA/600/R-17/276
August 2017
vwvw.epa.gov
Adsorption-based Treatment Systems
-------