United States EPA- 600 ' 8~ 87-027
Environmental Protection
Agencv Julv 1987
&EPA Research and
Development
DEVELOPMENT AND DEMONSTRATION
OF INDOOR RADON REDUCTION MEASURES
FOR 10 HOMES IN CLINTON, NEW JERSEY
Prepared for
Office of Radiation Programs
Prepared by
Air and Energy Engineering Research
Laboratory
Research Triangle Park NC 27711
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of
environmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the SPECIAL REPORTS series. This series is
reserved for reports which are intended to meet the technical information needs
of specifically targeted user groups. Reports in this series include Problem Orient-
ed Reports, Research Application Reports, and Executive Summary Documents.
Typical of these reports include state-of-the-art analyses, technology assess-
ments, reports on the results of major research and development efforts, design
manuals, and user manuals.
EPA REVIEW NOTICE
This report has been reviewed by the U.S. Environmental Protection Agency, and
approved for publication. Approval does not signify that the contents necessarily
reflect the views and policy of the Agency, nor does mention of trade names or
commercial products constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service. Springfield, Virginia 22161.
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ABSTRACT
In the spring of 1986, the New Jersey Department of Environmental Protec-
tion located a cluster of homes with extremely high radon levels in the town
of Clinton, New Jersey. Research Triangle Institute was contracted to develop
and demonstrate radon reduction techniques in 10 of these homes. The work was
to be completed before the 1986-87 winter heating season began.
The demonstration homes were selected from among 56 homes in the subdivi-
sion of Clinton Knolls. All of these homes had shown radon concentrations in
excess of 64 pCi/1 when monitored in the spring of 1986. Each of the homes
was inspected and a representative sample of 10 homes was selected for the
radon reduction demonstration project.
Following intensive diagnostic work and monitoring in each of the homes, a
rs.don reduction plan was developed. With the agreement of the homeowners,
installation of radon reduction systems was carried out during the summer of
1986. All of the 10 homes had radon concentrations reduced significantly by
the fall of 1986. The average cost of radon reduction was $3,127.
11
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TABLE OF CONTENTS
Section Page
List of Figures [[[ V
List of Tables .................. . ..................................
1.0 Introduction [[[ 1
2.0 Background. ... .............................................. ....... 2
3 . 0 Selection of Demonstration Homes ........... . ....................... 3
4.0 Diagnostic Procedures . Used Prior to Radon Reduction ................ 24
4. 1 Radon Grab Sample Measurements ............... .' ............. 26
4.2 Qualitative Measurements of Soil Gas Entry ................. 27
4.3 Characterization of Subslab Aggregate ...................... 27
4.4 Measurement of House "Tightness" ........................... 28
4 . 5 Whole House Fan Test ....................................... 32
4.6 Investigations of Negative Pressure Induced on
Basements .................................................. 32
4.7 Simulation of Winter Conditions ............................ 35
4.8 Increasing Makeup Air ...................................... 43
5.0 Radon Monitoring ...... -. ............................................ 47
5 . 1 Continuous Radon Monitoring ................................ 47
5.2 Charcoal Canister Monitoring ............................... 47
5 . 3 Monitoring Conditions ...................................... 52
5.4 Control Homes .............................................. 54
6 . 0 Development of Radon Reduction Plans ............................... 60
7 . 0 Installation of Radon Reduction Measures ........................... 63
7 . 1 Installation Materials ..................................... 63
7.2 Estimate of Installation Costs ............................. 63
7.3 Diagnostic Proceudres used Following Radon Reduction
Efforts ........... ... .............. . . ...................... 68
&. 0 Quality Assurance ....................................... _ .......... 69
8.1 Quality Assurance Objectives for Passive Scintillation
Cell Radon Monitoring ...................................... 69
8.2 Quality Assurance Objectives for Charcoal Canisters ........ 77
8 . 3 Systems Audits ............................................. 78
8.4 Seasonal Indoor Radon Variations ........................... 78
8.5 Control Homes .............................................. 79
9 . 0 Results and Conclusions ............................................ 81
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TABLE OF CONTENTS (continued)
Section Page
9.2 House C30A 81
9.3 House C39A .. 81
9.4 House CA6A ... . 95
9.5 House C10B......... .... .. 95
9.6 House C31B...... 96
9.7 House CA9B .'... 96
9.8 House C33C 96
9.9 House C32D 96
9.10 House C24E 97
10.0 Recommendations 98
REFERENCES 99
APPENDIXES
A Radon Reduction Plans A-i
B Homeowner Permission Form. B-l
IV
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LIST OF FIGURES
Number Page
1 Houses selected for radon screening « 4
2 Floorplan "A" 6
2 Floorplan "B" 7
2 Floorplan "C" and "D" 8
3 Pre-selection site survey checklist 9
4 Estimates of air infiltration rates by home using four different
models 29
5 Radon concentration vs. air exchanger rate for Clinton homes 30
6 Radon concentration vs. air infiltration rates for Clinton
homes 31
7 Effect of whole house fan use with all windows open, on radon
concentration 33
8 Fan flow curve for House C48B 34
9 Premitigation radon concentration, House C48B 37
10 Premitigation radon concentration, House C48B and Control
House C31B 38
11 Premitigation radon concentration, House C30A . 39
12 Premitigation radon concentration, House C33C • 41
13 Premitigation radon concentration, House C8A 42
14 The effect on radon concentration of producing a heat
differential to simulate winter conditions 44
15 PRO #123 response to temporal variations 48
16 PRO #124 response to temporal variations 49
17 PRD #125 response to temporal variations 50
18 PRD #127 response to temporal variations 51
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LIST OF FIGURES (continued)
Number
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
Premitigation monitoring results for House C48B and control
Ambient radon concentrations, Hebgen Park Monitoring Station,
C-i n-vr ,...•-._ j_r,,. AR-S #255 PRD #125
Pal •f'krat-i'nn data- AR-5 #258 PRD #127
House C30A: pre- and post-mitigation reduction results. ...«*...«
House C46A: pre- and post-radon reduction results
House C31B: pre- and post-radon reduction results »....
House C48B: pre- and post-mitigation reduction results, .........
House C33C: pre- and post-radon reduction results. ..............
House C32D: pre- and post-radon reduction results
House C24E: pre- and post-radon reduction results. ..............
Page
,. 53
. 57
. 59
73
74
75
76
82
83
84
85
86
87
88
89
90
. 91
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LIST OF TABLES
Number Page
1 Clinton Radon Levels ... 5
2 Assessment Summaries—Clinton 12
3 Distribution of Homes Included in Radon Screening by
Floorplan 22
4 Distribution Homes Selected for Demonstration..... 23
5 Pressure Difference Measurements for Two Homes 45
6 Control Homes Paired with Demonstration Homes 55
7 Summary of Radon Reduction Plans 61
8 Standard Parts Used in Installation of Radon Reduction
Systems 64
9 Cost of Radon Reduction Installations 65
10 Quality Assurance Objectives.... 70
11 Passive Scintillation Cell Radon Monitor Calibration
Constants . 71
12 Charcoal Canister Quality Assurance Samples 72
13 Approximate Reduction in Radon Concentrations Using
Charcoal Canister Data Following Application of
Radon Reduction Techniques (pCi/1) 80
14 Radon Concentrations as Determined with Charcoal Canisters... 92
vu
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1.0 INTRODUCTION
The discovery of high indoor concentrations of radon gas in the Reading
Prong area of New Jersey, New York, and Pennsylvania, and in other locations
in the United States, has raised serious concerns about a large number of
people being exposed to the radioactive gas. In response, the U. S. Environ-
mental Protection Agency (EPA) issued a guidance booklet, "A Citizen's Guide
to Radon: What It is and What to Do About It" (EPA, 1986a). EPA guidelines
recommend initiating corrective action in homes with radon concentrations in
excess of 4 picocuries per liter (pCi/1), or 148 Becquerels per cubic meter,
of air. At radon concentrations of 200 pCi/1, temporary relocation is recom-
mended.
In the early spring of 1986, a preliminary survey of homes in Clinton, New
Jersey, conducted by the New Jersey Department of Environmental Protection
(DEP), identified more than 50 homes with indoor radon concentrations greater
than 100 pCi/1 in the subdivision of Clinton Knolls. Many of these homes had
radon concentrations of 600 pCi/1 or higher.
The primary purpose of the work described in this report was to develop
and demonstrate cost-effective radon reduction techniques in 10 representative
Clinton Knolls homes. Radon reduction measures were to be completed before
the beginning of the 1986-1987 heating season to keep the exposures of
residents to a minimum. Additional data were collected to add to the general
body of information on radon transport and its control in homes; however, this
data collection was secondary to the pressing need to demonstrate effective
radon reduction techniques by the Fall.
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2.0 BACKGROUND
The subdivision of Clinton Knolls is located near the center of the town
of Clinton, New Jersey. The neighborhood is dominated by frame houses with
floorplans of approximately 139 m2 (1500 ft2). This uniformity is due to
development of the subdivision by a single builder. Some custom-built homes,
similar in style and size to the developer-built homes, are scattered among
those built by the prime contractor. While most of the houses are approxi-
mately 18 years old, many of the 56 volunteer homes that were surveyed were
still occupied by their original owners, making this neighborhood a stable
one.
The development is built on a dolomitic limestone hill that rises above
Main Street and ends at the edge of an abandoned quarry. The hill crests at
the interior streets of the subdivision with bedrock rising to the surface in
the area. Several homeowners reported that the bedrock beneath their homes
had to be blasted before basements could be built or before sewer lines could
be placed. Residents also reported the appearance of sinkholes throughout the
neighborhood where the formation of underground caves had caused the earth to
subside.
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3.0 SELECTION OF DEMONSTRATION HOMES
One hundred three homeowners who had participated in the DEP radon survey
in March and April of 1986 were asked to volunteer their homes for the radon
reduction demonstration effort. Fifty-six of the homeowners who volunteered
were selected for screening. Figure 1 demonstrates the proximity of the 56
homes participating in EPA's radon screening effort and Table 1 shows the
range of radon concentrations among the 103 homes participating in the DEP
radon survey.
Three basic floorplans repeated throughout the subdivision are reproduced
from the original developer's promotional brochure in Figure 2. In addition,
a small number of diverse floorplans built by independent contractors were
also investigated. For the purposes of this report, the floorplans have been
assigned the following letter designations:
• Split level with half basement (combination of slab-on-grade
and block basement) - A
• Bi-level (slab-below-grade) - B
• Two story with no basement (slab-on-grade) - C
• Two story with basement (concrete block basement) - D
• Independent builder floorplans (variety of substrates) - E
During a one week period, each of these homes was investigated t>y a diag-
nostic team of EPA and RTI personnel. Figure 3 reproduces the checklist that
was used to assess each of the homes. The objective of EPA's home screening
effort was to characterize the pool of homes and select 10 homes as repre-
sentative of the Clinton housing stock which could be used to demonstrate
radon reduction measures. Table 2 is a summary of findings; Table 3 shows the
distribution of survey houses by floorplan. Selection of 10 demonstration
homes from among the volunteers homes was done using the criteria below:
• The ability to identify and to access the location of radon entry
into the house.
• The ease of worker access to the home during the workday.
• The ability to reduce radon levels in the home with few
potentially unknown factors affecting the outcome, such as
fireplaces, woodstoves, etc.
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xxxxxx
Participated in
EPA radon screening
Figure 1. Houses selected for radon screening.
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TABLE 1. CLINTON RADON LEVELS
Concentration No. of Houses % of Sample
pCi/1
>2048 2 1-9
1024-2047 3 2.9
512-1023 13 12.6
256-511 17 16.5
128-255 17 16.5
64-127 12 11.7
32-63 12 11.7
16-31 14 13.6
8-15 5 A.9
4-7 6 5.8
<4 2 1.9
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' I ' ' LL Family Room
Kitchen (J 15'x14'
Lavl14'9"x10'10"
Garage
20'x10'4"
Down
Bedroom
12* x 9'
Bath/
klE
Bedroom
12'8"x12'8'
Dining
Room Foyer
1Vx11' Ic
I ^
Portico
Down
Living Room
18'4"x13'
c \ C
Bedroom
12'xir
Source: Clinton Knolls subdivision advertising brochure
Figure 2-a. Floorplan "A"
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Recreation Room
20'4"x 11'6"
T
Laur
Garage
23'4" x
Bedroom \
Storage
11*6" x
Source: Clinton Knolls subdivision advertising brochure
Dining
Room
9'0" x
10'0"
Kitchen
13'6" x
10'0"
IT
Bath1!
Bath
Bedroom
14'8"x 11'
C I C
Living Room
8'4"x 11*3"
UpDn
u
Bedroom |C| Bedroom
10'2"x
9'0"
Figure 2-b. Floorplan "B".
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Dining Room
25'4" x 13'4"
Living Room
I P I
Kit Dinette
^ 21 '4" x 9'0"
PanM D|
— I
C , Family Room
18'0" x 15*8"
Up
Laundry
n
i — ' —
Garage
Bedroom
1VO"x
10'0"
Hfltn urBss ** i
. i Bedroom
\I TWalkT 15'0"x
IB| | inC 1T6"
C T Hall Dn '
Bedroom ~~ /
I3'4"x11'8" c C Bedroom
j-L 15'8" x 10'0"
Storage
Source: Clinton Knolls subdivision advertising brochure
Figure 2-c. Floorplan "C" and "D'
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Survey Crew Members
General Instructions
Thia checklist is designed to ensure that each house is thoroughly
evaluated. FILL IN ALL SPACES ON THIS CHECKLIST. All sketches, notes, and
»easure»ent results should be recorded in the field notebook along with the
house address and survey number, date, time, and names of the crew members.
I. Sketch a floor plan of the house. Also provide a sketch of the house
elevation. If a house lacks one of the features listed then write MNA" in the
space provided. Otherwise sketch the dimensions of the Basement and/or Crawl
Space. Check off each item as it is completed.
Floor plan
Basement
_„_, Crawl Space
Fireplace(s) and Chimneys
Stairwell(s)
Bathrooms
______ Overall floor plan dimensions (length x width)
Basement dimensions (length x width)
Elevation
Interior block walls
Structures penetrating basenent slab
Exterior slabs: patios
Exterior slabs: attached garage
Figure 3. Pre-selection site survey checklist.
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II. Provide a detailed sketch of the Basement and/or Crawl Space. Check off
each item as that ha« been included or write "NA" if it ia not present.
Sump pump
Floor drain .
Windows/vents
Pipe penetrations
Cracks in floor/walls
____ Outside door to basement
____ Crawl apace door to inside
III. Miscellaneous Information. Answer as indicated or write "NA" if the
question is not appropriate.
Is the basement finished?
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IV. Measurement checkliat. Check off each measurement as it is taken or
write "NA" if not applicable. Record the tine and location of each
measurement in the field notebook.
Integrated Samples (Charcoal canniaters/bags)
Basement
Crawl Space
Living/Family Room
Grab Samples
Air samples (Scintillation cells)
Sump pump
_rm_ja_ Floor drain
Wall/Floor cracks
____ Crawl space
Other:
Working Level measurements (Filter samples)
_ Sump pump
Floor drain
Wall/Floor cracks
_____ Crawl space
Other:
Figure 3 (continued)
11
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON
Radon
concentration
lowest
House f'loor Number Number of
nniiihor (|>CI/I) of adults smokers
Number and ages
of children Type
Features
CIU'
C2A
160
103
89
16. 19
18. 20
17. 14. 10
two-story colonial,
no basement
split level with
basement—
unfinished
bl-level
standard
sump with pump; attic fan; open
block-plaster
has photos of house being built;
block halfway up front and one
aide; good access to block wall
from closet; water closet leak;
negative pressure hot air furnace/
dryer/bath fan upstairs; thermal
bypass-kitchen soffits/chimney/
bath chase (tub); pipe penetra-
tions with wood stakes
C4A 676 3 0 0 split level-
unfinished
C5D 114 2 0 15. 13 bl-level
<:<>A 25S 2 0 0 split level
addition over patio; many cracks
poured concrete floor
concrete block; whole house fan
eight months In house; many wall
cracks and floor/wall seam/floor
cracks; some open blocks/poles
(support); no sump at floor draii
In
n
<; denotes Clinton study
number (1-56) denotes assigned project number
letter (A-K) denotes floor plan
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
House
number
C7E
C8A
C9B
C10U
c 1 1 it
C1D2
ciai;
Radon
concentration
lowest
floor Number Number of Number and ages
(pCl/1) of adults smokers of children
250 2 0 6. 9
791 2 0 6, 7, 10. 13
186 2 1 6
418 2 0 0
250 2 1 0
608 2 0 12, 9
lf)T> 2 1 0
Type
bl-level
split level —
finished
bl-level
bl-level
bl-level
colonial with
basement —
unfinished
other-multilevel —
finished with
crawlspace
Features.
homeowner capable of doing variation
remediation work has repaired rotted
sill; all at grade level
basement finished but owner willing
to remove wall paneling, etc.
standard
owners both work — willing to vacate
house to have work done
block front; wood stove In family
room; closet access to block
whole house fan; several large
cracks and openings; coal stove;
bedrock In northeast corner of lot
woodstove; all abovegrade; slab
poured against 4 Inch block;
2 ft x 3 ft chase at head of
bathtub
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
nation
concenlrutlun
lowest
House floor Number
number (pCl/1) of adults
Number of Number and ages
snokers of children Type
Features
CHI) 437
C15E 411
TlfiE 495
6. 10
bi-level
bl-level, but
not Lackland;
other, finished
basement
coal stove In basement; penetration
(water plpe/tollet/perlraeter crack)-
closet access to 1/2 block wall;
negative pressure (furnace/dryer/
bath fan/coal stove); bypasses:
whole house fan/chlnney/kltchen
soffit/bath chase; stone wall behind
brick surround for coal stove
owners scheduled to relocate soon;
block wall to grade
standard
C17A 150
4.5
split level with
unfinished basement
basement entry from first-level garage
penetrations: open blocks (1/2).
Jackposts, cracks In floor, two oil
lines; negative pressure-boiler/
dryer/chimney bypass/whole house fan;
AC In attic; may be easy to isolate
attic
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
Rndon
conconlrutlon
lowest
House floor Number Number of
number (pCi/1) of adults smokers
Number and agea
of children Type
Features
CI8A
79
CI9A 163
C2AO 150
122
101
split level on
slab, no basement
17. 16. 13. 7
19, 17. 8
1. 4
18. 14
split level,
partially finished
basement
split level with
basement
split level with
basement
slab on grade; penetrations: main
In laundry/outside faucet from
bath/two toilets; dishwasher/bath
sinks/kitchen sinks/shower and tub
drains; negative pressure-one bath
fan/dryer/attlc scuttle soil vent/
kitchen soffit
hot water heater; two sump holes;
finished garage (two steps down);
horizontal break In block at back
of house approximately 1/4 Inch
finished basement; added on garage
and basement for garage
block open at top; fan moves air
from basement to upstairs;
basement partially finished;
wood stove
split level, base- two bathtubs on slab (currently
ment under addition, being renovated); wood stove and
unfinished fireplace; no expansion Joint;
garage converted to bedroom; HV
ducts above slab
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
Radon
concentration
lowest
House floor Number Number of
number (pCl/1) of adults snokers
Number and ages
of children Type
Features
C23B
C24E
423
426
18. 20
bl-level
bl-level
C25B
C2(iU
C27B
C2HC
C2A9
C.'tOA
252
249
93
720
148
2.254
2
1
2
2
2
2
1
1
2
1
0
0
0
4
7. 12. 17
2
3 Months
0
bl-level
bl-level
bl-level
colonial, no
basement
split level
split level
coal stove; block In front; reno-
vating lower level; all ventilated
different from Lackland houses;
a true split with earth floor
crawlspace
crawlspace
wood »tove and reclrculatlng
exhaust fan; French drain
approximately 12 feet from front;
block front; two-story addition
on patio; electric heat
one bath upstairs (not two)
wood stove
finished basement
duct under slab upper level; two
elderly people do crafts In base-
ment; several top of block openings/
sump hole/wall cracks; high pitched
roof; windows never opened, some
sealed; owners not likely to do
much on own
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
Radon
concentration
lowest
House floor Number Number of
iiiiinbur (pCl/l) of adults smokers
C3B1 691 2 1
<::ii!li 1.357 3 0
(J.IJC 1.190 3 0
i::tlH GI9 3 1
C35A 1,250 2 0
C3B6 360 3 0
Number and ages
of children Type Features
8, 6. 4, 2 bl-level block front, partially below grade
0 colonial unfinished add on room with crawlapace; concrete
basement, added slab; original owner; a good
crawlspace candidate to confirm the effective-
ness of remediation methods at
Boyestown
3 grown colonial, no remedial measures begun
basement
17. 10 bl-level concrete patio slab; music teacher's
house; block front, partially below
grade
0 split level translte all along back wall behind
garage
1, 5 bl-level ten-year residents both work; wood
stove In corner; 1/2 block In front
(front only, approximately 1/3 dirt
or block); blocks exposed under front
foyer; open stone patio off family
room; only central opening to wall,
no side closet
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
CD
Radon
concentration
lowest
House floor Number
number (pCl/1) of Adults
Number of Number and ages
smokers of children Type
Features
<::JB7 440
t30A 321
i::i'JA 1.500
120
500
265
3
none under 7
10. 12
15. 12. 9
9. 5
respiratory
problems
17
bl-level
split level
split level,
unfinished
bl-level
large, old, custom
house
split level
bath tub on slab; sample taken at
water stake hole through slab; block
on front; wall to grade
12 ft x 16 ft addition behind family
room with crawlspace and vents; sump
open; attic fan (not whole house)
typical basement openings; typical
subfloor ductwork; coalstove In
addition
daycare. two children under age 7
laundry slightly different
Interior block walls under fireplace;
root cellar
attic fan; basement door to outside
with concrete; steps to cellar door-
Inside door cut through block
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
Radon
concentration
lowest
llinisi! floor Numher Number of
number (pCl/1) of adults smokers
Number and ages
of children Type
Features
-inn
99
bl-level
I.-I5B
( ICfiA
IM7B
(MSB
451
226
635
686
936
0
0
21. 16
19. 18. 14
split level
bl-level
split level
bl-level
bl-level
1/2 block wall on front with closet
access; entry points-toilet/
showers/water pipes (two stakes);
negative pressure (furnace/dryer/
cold air return/bath fan/gas DHW/
normal bylead bypasser; lived here 2
years; asbestos shingles
fireplace (but not a significant
factor)
fireplace
original owner; partially finished
basement
original owner, witnessed construc-
tion; bedrock close to surface; block
wall grade
fifteen-year resident; plan with back-
to-front family room; raised bl-level;
15x15 foot patio; asphalt drive and
carport to wall; son sleeps In
basement; cracks on concrete slnb
visible on patio
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
Radon
concentration
lowest
House floor Number Number of
number (pCl/1) of adults smokers
Number and ages
of children Type
Features
iMA'J
823
135
C5HA
157
403
0
0
1 Month. 2
0
split level. one adult works at hone; 1/2 bath
unfinished basement off kitchen removed; leakage and
cracks In basement-house and garage-
house; open sump
colonial, no base-
ment
bi-level
bl-level
split level,
finished basement
subslab heat ducts; whole house has
wallpaper and paneling; garage
converted to bedroon; stone fire-
place; potentially many entries;
slab penetration-toilets/ductwork/
water main; negative pressure-
furnace/fIreplace/bath fan/bypass
block in front
fireplace-raised hearth with ashpit.
outside access; block at front
fireplace; renovated both bathrooms
covered register In bathroom off
kitchen; no chase in bathroom
(continued)
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TABLE 2. ASSESSMENT SUMMARIES—CLINTON (continued)
Radon
couoontration
lowest
Door Number
r (pCl/J) of adults
Number of Number and ages
smokers of children Type
Features
('."> IA
400
split level with
unfinished basement
<;r>f>A
131
split level
252
bl-level
owner attempting subslab vents (5);
has garage In 1/2 of basement;
basement penetrations but solid top
course; runs coal stove In winter
(added room up on posts, open
beneath); negative pressure furnace; -
has soil pipe and AC drain
full basement and garage under house;
floor drain-to daylight-fan
currently sucking; fan on kitchen
hood; whole house attic fan; plaster
gap; pipes sealed
similar construction details to house
C23B
-------
TABLE 3. DISTRIBUTION OF HOMES INCLUDED IN RADON SCREENING BY FLOOR PLAN
Floorplan
A B C
Number 22 22 3
of houses
D E
3 6
• The radon concentration in the home must be above 64 pCi/1
according to the DEP screening measurements.
• The 10 homes should show an even distribution of substructures,
that is, approximately half should be slab-on-grade construction
and half should have basements. At least one of the
demonstration homes should have a crawlspace.
• A high degree of homeowner cooperation.
• Homes with young children whose lungs are still developing should
be well represented in the. selection.
• Special consideration should be given to homes that are occupied
a large portion of the day, especially if a basement or slab
level is used as a play area or sleeping area. Duration of
residency is also considered.
• The presence of smokers is considered as a positive factor in
home selection because of possible synergistic effects.
• Some of the selected homes should be more difficult to achieve
radon reduction in because of finished lowest floor space.
Table 4 shows the distribution by floorplan of the homes selected for the
demonstration study. All of these homes had radon concentrations in excess of
200 pCi/1 in the DEP screening, and four of the houses had concentration in
excess of 1000 pCi/1.
22
-------
TABLE 4. DISTRIBUTION OF HOMES SELECTED FOR DEMONSTRATION
Construction Design
(substructure) House Number
Split Level C8A
(combination slab-on-grade C39A
and block basement) C30A
C46A
Bi-level C31B
(slab-below-grade) C10B
CA8B
Two-story
(slab-on-grade) C33C
(block basement) C32D
Other
(combination slab-on-grade C2AE
and dirt crawlspace)
23
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4.0 DIAGNOSTIC PROCEDURES USED PRIOR TO RADON REDUCTION
At the time work was initiated on the homes in Clinton, only a small
amount of experimental data was available to assist in selecting techniques
for assessing suitable radon reduction methods in homes. The EPA guidance
document, "Radon Reduction Methods: A Homeowner's Guide" (EPA, 1986b) and
publications describing similar radon reduction efforts (NYSERDA, 1985; EPA,
1983; Nazaroff, 1985; Turk, 1986; Henschel, 1986; Nitschke and Brennan, 1986)
provided a basis for the development of diagnostic and radon reduction
approaches. Diagnostic techniques focused on the detection and isolation of
three main mechanisms of radon entry and transport in a structure:
• Simple transfer through substructure openings. Radon enters into
a house through openings connecting the house substructure to the
soil. These entrance ways need not be very large to constitute a
significant radon pathway. Small slab-cracks, hollow pipes, sump
holes, or any other features that penetrate the foundation of the
house are likely sources.
• Negative pressure driven transport. Negative air pressure over
the portion of the structure with soil contact results in a
pressure-driven transport of radon and other soil gases into the
house. Negative pressure can be induced by the use of fans,
appliances, and natural ventilation in the house.
• Thermally driven transport. Differences in temperature between
the soil-contacting portions of the building and the rest of the
structure due to normal heating of the home may give rise to the
thermally driven 'transport of radon from the soil into the house.
Although numerous sources have confirmed these general mechanisms, little
information is available on the effect on indoor radon levels as the three
mechanisms interact with one another in a house, nor are there data describing
the interactive effects of other factors such as the tightness of a house or
the operation of an assortment of common indoor venting devices such as a
whole house fan.
Consequently, diagnosis of the 10 homes in Clinton was performed using two
approaches. The first approach was to identify and characterize all possible
sources of in-leakage, negative pressure, and thermally induced transport in
each house. The second approach was to simulate, in isolation, conditions
24
-------
that might enhance or reduce radon transport and then measure the actual
effect. The second approach was used in a small number of homes. Experiments
in this latter category include:
• Measuring the effect of whole house fan operations
• Investigating the negative pressure induced on the basement by
the use of various household appliances
• Using a high volume fan to simulate winter-time stack effect
• Measuring the effect that furnace operation has on basement
pressure.
• Experimenting with supplied outdoor makeup air to reduce negative
pressure.
In all cases, the objective of the diagnostic procedure was to understand
the mechanism and identify sources of radon infiltration to develop a low-cost
and effective radon reduction strategy for each of the demonstration homes.
4.1 RADON GRAB SAMPLE MEASUREMENTS
Radon grab samples were obtained using a Pylon scintillation cell in con-
junction with a Pylon AB-5 fitted with a Lucas cell adapter. Procedures as
described in the EPA document "Interim Indoor Radon and Radon Decay Products
Measurement Protocols" (EPA, 1986c) were followed. Grab samples were used to
identify suspected soil gas entry routes. In all homes with sump holes, grab
samples were taken in the stream of air exiting the footer drain pipe. Other
common locations for effective grab sample collection were:
• Air spaces in unpaved crawlspaces
• Wall cavities
• Inside open cinder blocks
• Air exiting a hole drilled in a concrete block wall or slab floor
• Air in subslab heating ducts.
Although grab sampling can be misleading, in combination with other meas-
urements, it proved very useful in identifying major soil gas entry routes.
Appendix A provides a detailed summary of each of the 10 demonstration homes
25
-------
and lists the results of individual grab samples taken in each of the homes in
the "Diagnostic Investigation" section of the summary.
If the grab sample concentration can be combined with the measurement of
soil gas flowrate from an opening to the soil, then a source strength can be
calculated (for the conditions under which the measurement was taken). The
concentration and flowrate are dynamic and are affected by air pressure dif-
ferentials, snow cover, precipitation, and even by time of day. An example
source term calculation was made for house C30A. A soil gas flowrate of 2,550
pCi/1 was measured entering the building from the footer drains in the sump
hole. The radon concentration in a grab sample of the air from the sump hole
was 36,000 pCi/1. Under the measurement conditions (approximately 2 to 3
pascals of negative pressure due to both the furnace and clothes dryer opera-
tion) , this measurement corresponded to a source term of over 91 million pCi/1
and would account for an indoor concentration of between 600 to 1,200 pCi/1
given an air exchange rate from 0.5 to 1.0 air changes per hour (ACH) . Be-
cause air concentrations of radon were from 1,400 to 2,700 pCi/1 in this home,
the sump hole was considered to be the largest but not the only source of soil
gas infiltration to the house.
Efforts were made to measure the difference in pressure between the inside
and outside of the house while grab samples were being taken. Because factors
such as windspeed, and furnace or fan operation can affect the flow of soil
gas substantially, pressure difference information allows a reasonable inter-
pretation of seemingly anomolous radon grab sample results and results from
other techniques designed to determine the rate and location of radon entry.
Pressure difference measurements were made using low range 1.24 to 62.0 pas-
cals (0.005 to 0.25 inches of water) magnahelic gauges.
4.2 QUALITATIVE MEASUREMENTS OF SOIL GAS ENTRY
In all cases, extensive visual examinations were made of the floors,
joints, and undergrade walls of each home to identify potential entry points.
A simple smoke tube test was then made at any potential site of entry to
determine the direction of airflow. If the smoke was blown back into the
room, the opening was considered to be a possible point of radon entry.
Although this test does not determine the radon content of the incoming air
stream, it does locate potential influx sites. Because factors such as
26
-------
windspeed and direction can greatly affect smoke tube results, outdoor and
indoor conditions were noted and pressure difference measurements were made
wherever possible.
4.3 CHARACTERIZATION OF SUBSLAB AGGREGATE
Because of the high radon concentrations encountered in the 10 demon-
stration homes, it seemed likely that soil depressurization techniques would
be necessary. Consequently, all houses were inspected in an attempt to
determine the composition of the subslab aggregate.
The subslab material was inspected visually by drilling holes in the slab
with a hammer drill. A flashlight through a 1-inch hole was frequently suf-
ficient to view the subslab material.
When an actual visual inspection of the subslab was impossible or uninfor-
mative, several indirect methods were used to determine if the material was
porous enough to allow effective soil depressurization.
With a hole drilled through the slab and negative pressure applied to the
basement using a fan or some other technique, a smoke tube over the hole was
used as a visual inspection technique. If the smoke was forced out of the
hole, subslab entry of soil gases was suspected. At this point, an additional
technique might be used.
To determine the subslab characteristics, a second slab hole was drilled.
At one hole, a vacuum cleaner was sealed over the hole to apply suction on the
subslab material. At the other hole, a smoke tube was used to determine the
effect of suction through the aggregate. More quantitative results were
achieved with the substitution of an inclined manometer for the smoke tube to
actually measure the pressure gradient through the subslab material.
A more elaborate method of assessing subslab material was developed using
freon gas (standard 15-pound cylinder) as a tracer and a halogen detector (TIF
model 5500: TIF, 9109 N.W. 7th Ave., Miami, FL, 33150) to follow the freon
transfer into the building. Freon is injected through a hole in the subslab,
and the detector is used as a sniffer to locate relative changes in freon
concentrations in the building. A low concentration of the gas is sufficient,
and the lowest detectable concentration should be used at all times. This
technique was particularly useful in detecting problems in already installed
radon reduction systems.
27
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4.4 MEASUREMENT OF HOUSE "TIGHTNESS"
House tightness is used, in the context of this report, to indicate rela-
tive leakage area in a house. Air exchange rate measurements were made on
each of the 10 homes in Clinton using a standard blower door test (ASTM Method
No. E779-81). The measurement results, forming part of each home's profile,
are presented in Appendix A. One purpose of these measurements was to deter-
mine if high indoor radon levels in the Clinton homes could be attributed to
the tightness of the structure. The major objective, however, was to deter-
mine the extent of leakage into the house. If the leakage was extensive,
structural rebuilding might have been necessary in order for the radon reduc-
tion efforts to be effective. If tightness showed a good correlation with
high radon levels, radon reduction measures might concentrate on compensating
for the low volume of available dilution air 'in a house.
Data from blower door measurements were fitted using various models for
the prediction of air exchange" rates. Figure 4 compares the results of four
of these models using data from the 10 demonstration homes. A brief descrip-
tion of each of the models used is provided in "Indoor Air Quality, Infiltra-
tion and Ventilation in Residences" (NYSERDA, 1985). Predicted air exchange
rates using the Shaw model were higher in all cases and considerably higher
for eight of the ten homes than were the air exchange rates predicted by the
three other models. Consequently, the Shaw model results air exchange rates
were not used in the following dicussion.
Infiltration rates predicted by the models range from 0.4 to 1.1 ACH with
an average of 0.62 ACH (excluding results from the Shaw combined modal).
Figure 5 shows a plot of the estimated air exchange rates in the ten houses
using the results of the Sherman (1980) model versus the DEP screening study
charcoal canister radon concentration results for each home. Figure 6 shows
*
the same plot, superimposing a curve that represents the best fit to the data.
Correlation was low with a coefficient of correlation value of 0.60.
On the basis of these results, it was concluded that the extremely high
radon concentrations encountered in the Clinton homes were not due to the
tightness of the structures, but were more likely due to the unusually high
source strength. For dilution ventilation alone to provide a sufficient
reduction in radon concentrations, the airflow through these homes would have
28
-------
z
0
3.0
2.5-
2.0-
u
Modal Nam«
| Kronval, 1980
3 Shaw,1981
H Shaw/Brennan*
3 Sherman, 1980
C24E C39A C10B C32D C31B C46H C3B
HousalD
C4SB
C33C
C30A
* in NYSERDA, 1935
Figure 4. Estimates of air infiltration rates by home using four different models.
29
-------
3000
2000
o
1
o
o
•g
DC
1000
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
Air Exchange Rate (ACH)**
•Activated carbon detectors from New Jersey DEP.
"Infiltration estimates from LBL model.
Error estimation for air exchange rates. Personal communication with
Andrew Persily, NBS
Figure 5. Radon concentration vs, air exchange rate for Clinton homes.
30
-------
X
u
w
I
*»
w
7:
e
u
S
3000
2000-
1000-
y » 3375.6082 • 10'(-0.8914x) R * 0.72
0.0 0.2 0.4 0.6 0.8 1.0
Air Exchange Rat* (ACH)
1.2
1.4
Figure 6. Radon concentration versus air infiltration rates for Clinton homes.
31
-------
to be increased from approximately 5.66 m /min (200 cfm) to a rate of 707.9
3
m /min (25,000 cfm). The cost and discomfort presented by this option indi-
cated that radon reduction methods that concentrated on lowering the entry
rate of gas to the homes would be more effective and practical.
A.5 WHOLE HOUSE FAN TEST
A test was made to gain some insight into the potentially competing ef-
fects of increased soil gas entry versus added dilution air when a whole house
fan was used to ventilate a building. The results are shown in Figure 7. Al-
though the fan dramatically increased ventilation (in the neighborhood of 57%
[2,000 cfm]) the large negative pressure differential (^28 pascals) increased
the rate of soil gas entry sufficiently to overwhelm the diluting effect.
This test was made in only one house and the results depend upon factors that
may be peculiar to the individual building, soil gas and soil characteristics.
4.6 INVESTIGATIONS OF NEGATIVE PRESSURE INDUCED ON BASEMENTS
In the majority of houses, differential air pressure measurements between
basement air and outside air were made. Temperature-driven stack effects and
mechanical equipment effects were isolated and the induced pressure differ-
ences measured. It was found that:
• Dryers and bathroom fans resulted in a 1 pascal or less negative
pressure on a basement.
• Furnaces in the 17,612 to 21,134 joules/sec (100,000 to 120,000
British thermal units per hour [Btu/h] range put 2 to 3 pascals
(0.008 to 0.012 inches water) negative pressure on a basement.
• Differential temperatures of -6.7 to -1.1 *C (20 - 30 *F) resulted
in 1 - 3 pascals (0.004 to 0.012 inches water) of negative pressure
on a basement.
During the AP measurements described above with a furnace running, makeup
air was drawn from the attic down the cavity around the chimney. In building
C48B, this amounted to approximately 1.42 m /h (50 cfm). Measurement of the
airflow from the furnace exhaust at the chimney top showed airflow rates of
between 2.8 and 5c7 m /h (100 and 200 cfm). Figure 8 (a fan-flow curve for
House C48B) shows an induced negative pressure of 1 to 2 pascals (0.004 to
0.009 inches water) at 5.7 m /h (200 cfm), reflecting the pressure difference
actually measured in the house when neither the furnace nor the clothes dryer
32
-------
5-20 7:30 9:30 11:30 1:30 3:30. 5:20 7:30 9:30 11:30 1:30 3:30
P.M.
Figure 7. Effect of whole house fan use with all windows open on radon concentration.
33
-------
z
u.
u
c
<
10 20 30 40
Pressure Dif«r«ntial (Pascals)
50
60
Figure 8. Fan flow curve for house C48B.
34
-------
were in operation. Blower door generated fan-flow curves (as measured with
blower door tests) were found to be useful in estimating the volume of makeup
air required to compensate for basement negative pressures. The curves, when
put to this use, were most accurate when generated from data collected with
the blower door placed in a basement access door.
To reduce a negative pressure of 3 to 4 pascals (0.012 to 0.016 inches
water) to 0 pascals (0 inches water), it was found that between 0.65 and 0.93
22 2
m (7 ft to 10 ft ) of window area must be opened to the outside.
It is difficult to make low AP measurements in the field. Field instru-
ments are only reliable to a lower limit of about 1 pascal (0.004 inches
water). Even low windspeeds have a large impact on the pressure fields
surrounding a house. Measurements were made when windspeeds were undetectable
to avoid the confounding effects of wind. Toward the end of the diagnostic
work, these measurements were made using a more sensitive electronic device
assembled using standard pressure transducer and digital display components
purchased from Modus Instruments (481 Gleason Rd., Stow, MA, 01775). This
system has a lower detection limit of 0.25 pascals (0.001 in water).
4.7 SIMULATION OF WINTER CONDITIONS
Data from a variety of sources have confirmed that winter-time indoor air
concentrations of radon are higher than even those taken under closed house
conditions in other seasons (Turk, 1986). It has been speculated that ele-
vated winter concentrations may result from:
• The formation of a nearly impermeable cap of either frost in the
upper soil or a layer of melting snow inhibits diffusion of radon
into the air from the ground surface and results in high
concentrations of radon in the soil gas.
• Combustion heating equipment and a temperature-induced stack effect
in a house produces a negative pressure on the basement. Makeup air
for this suction is drawn into the house from outside above grade,
but some fraction of it is drawn through cracks and holes in the
belowgrade foundation (Turk, 1986).
Pre-radon reduction continuous monitoring measurements in the 10 homes
were made in the early to late summer. Post-radon reduction continuous moni-
toring measurements were made in the early to late fall. Because these meas-
urements spanned a variety of weather conditions but never winter conditions,
an attempt was made to simulate winter conditions during some of the pre-radon
35
-------
reduction monitoring. It was not possible to induce ground-freezing condi-
tions; however, it was possible to simulate basement depressurization and a
temperature-induced stack effect.
A 50.8 cm (20-inch) diameter three-speed window fan was placed in a
livingspace window while radon was monitored continuously using a Pylon AB-5
and passive scintillation cell. For one-third of the monitoring period, the
house was in closed conditions with the fan off; during the second third of
the sampling period, conditions were identical except with the fan on; and
during the third part windows were opened with no fan operating.
In the first house monitored CA8B (Figure 9), the fan was on with the
house closed, followed by the fan off with the house open. The sampling on
this house did not include a period when the house was closed and the fan was
off. The average concentration for the first period was approximately 700
pCi/1, which compares favorably with the values of 964 and 542 pCi/1 measured
with activated carbon in the same location by DEP two months earlier (April 6
to 9 and April 16 to 19). During monitoring in June, the outside temperature
averaged approximately 22.8 *C (73 *F). DEP monitoring periods were 9.4 *C
and 10 *C (49 *F to 50 *F). The fan induced 7 pascals (0.03 inches water) of
negative pressure across the building shell. When the fan was shut off, the
concentration dropped quickly to less than 10 pCi/1, then for .the remainder of
the fan off, house open period, radon concentrations varied in a distinctive
diurnal cycle with peaks in the early part of the day and minimum levels in
the late afternoon. Control homes, selected for proximity and construction
detail similarity to a demonstration home, were monitored simultaneously. As
can be seen in Figure 10, this same diurnal cycle was observed over the same
time period in the control house C31B.
The second house, C30A, was monitored from June 7 through 14 using the
Pylon passive radon monitor. Samples were taken during three monitoring
periods (fan off, house closed; fan on, house closed; and fan off, house
open). The results are shown in Figure 11. During the first period, the
concentration rose quickly after the windows were closed and peaked at 1,300
pCi/1 near 5:00 a.m. on June 8, followed by a drop until 11:00 a.m. on June 8
when the window fan was turned on, producing a negative pressure of 8 pascals
(.032 inches water) on the building. At this point, the level of radon
increased very quickly to a much higher peak of 2,600 pCi/1 and averaged
36
-------
1500
« 1000
e
500
Fan Off — Windows Open
5/29 5/30
5/31
6/1 6/2 6/3
Days (end of day is midnight)
Figure 9. Premitigation radon concentration, house C48B.
37
-------
10,000
1,000
o
a
CC
PM AM PM AM PM AM PM AM PM AM PM AM-
5/29 5/30
"VVV" Te« Home
+ 4 % Control Home
5/31 6/1 6/2
Time
6/3
Figure 10. Premitigation radon concentrations, house C48B and control house C31B.
38
-------
3000
S 2500-
U
e
4*
L
e
u
g
2000-
1300-
1000-
500-
F an Off - Windows Open
6/7 6/8 6/9 6/10 6/11 6/12
Days (End of Oiy is Midnight)
6/13
6/14
6/15
Figure 11. Premitigation radon concentration, house C30A.
39
-------
approximately 2,075 pCi/1 for the monitoring period. This compares well with
the DEP (activated carbon) values of 2,254 and 2,141 pCi/1 for the same loca-
tions on April 7 to April 14 and April 16 to April 19, respectively. At 3:00
p.m. on June 10, the fan was removed and the windows opened. The radon level
in the house plummeted to a low of 60 pCi/1 at 7:00 p.m. and then showed the
familiar diurnal cycle seen in all the houses monitored in Clinton.
The third house, C33C (Figure 12), was monitored June 16 to June 24 using
three monitoring periods — fan off, house closed; fan on, house closed; and fan
off, house open. The effect of the fan-induced negative pressure was drama-
tically different in this house from that in either of the first two homes
monitored. When the fan was turned on, it caused very wide radon con-
centration excursions, ranging from a low of 100 pCi/1 to a maximum of 2,500
pCi/1 over a period of 12 hours. The average concentration during the fan-
off, house-closed periods was about 1,375 pCi/1 as compared with 1,530 pCi/1
measured by DEP (activated carbon) in the same location on March 14 to 17-
For the fan-on, house-closed period, the average was 922 pCi/1. In this
house, the floor was a slab-on-grade with heating ducts under the slab. When
examining the holes in the slab made for the warm air grills, it was found
that all of the soil beneath the slab had subsided, leaving a 2.5-10.2-cm (1
to 4 inches) cavity between the bottom 'of the slab and the earth surface
(except where there were grade beams under the load-bearing walls). A poly-
ethylene vapor barrier was found in very good condition stuck to the bottom of
the concrete slab. This left a large surface area of exposed earth in direct
convective contact with the living space air. When the fan was shut off and
the windows opened, the average concentration dropped to about 300 pCi/1 and
the familiar diurnal cycle was seen, even in this unoccupied house.
The results from house C8A are shown in Figure 13. The average concen-
tration for the fan-on, house-closed period was 465 pCi/1 compared to DEP
measurements of 791 and 1650 pCi/1 taken at the same location on March 22 to
25 and March 28 to 31. The average concentration for the fan-off, house-
closed period was 415 pCi/1. After the fan was turned off and the windows
opened, the average concentration dropped to 250 pCi/1 and the diurnal cycle
reappeared.
An experiment to simulate thermally driven effects was also made. The
temperature in one of the buildings was raised to induce stack effect negative
-------
3000
^ 2500 -
Fm On
§
e
2000-
1500
0
1000-
500-
Fan Off - Windows Open
Activated Carbon
6/16 6/17 6/18 6/19 6/20 6/21 6/22 6/23 6/24 6/25
Days (and of day is midnight)
Figure 12. Premitigation radon concentration, house C33C.
41
-------
e
e
fit
800
700
600
500
400
300
200
100
Fan Off - windows Still Closed
Fan On
Windows Closed
Windows Open
Activated Carbon
6/25
6/26 6/27 6/28 6/29
Days (Day Ends at Midnight)
6/30
7/1
7/2
Figure 13. Premitigation radon concentration, house C8A.
42
-------
pressures by running the furnace simulating combustion appliance draft. The
results are shown in Figure 14. Radon concentrations were continuing to rise
when the experiment was interrupted.
Negative pressures were induced by both the furnace and the temperature
differential in house C48B as shown in Table 5. Essentially, the furnace
produced on indoor/outdoor temperature differential of 22 *C (71.6 *F)
resulting in approximately 4 pascals (0.016 inches water) negative pressure on
2 2
the basement. Opening the 0.65 m (7 ft ) of attic hatch in the ceiling
appeared to increase the negative pressure 1 or 2 pascals (0.004 or 0.008)
from 4 pascals (0.016 in water) to 5 or 6 pascals (0.020 to 0.024 in water).
Due to the difficulties in measuring small pressure differences across
building shells, these measurements are preliminary.
It is clear that a fan-induced negative pressure on a house has an impact
on the radon concentrations in that house. In some houses, the technique
appears to adequately simulate winter-time entry rates even in the summer,
while in others there is little to distinguish a house monitored under simu-
lated winter conditions from the same house monitored under closed-house con-
ditions. Winter conditions cannot be uniformly simulated during the summer.
The ground is not capped with snow or frost. A fan induces a negative pres-
sure over the entire building shell whereas in typical winter conditions the
basement is under the highest negative pressure and the top of the house is
under positive pressure due to the buoyancy of the warmed air that is driving
the stack effect. A fan will bring in approximately twice as much dilution
air as the temperature-driven stack effect for the same negative pressure put
on the basement. Running the house at 22 *C (71.6 *F) warmer than the outside
air will reduce the artificial introduction of dilution air. However, the
method is impractical for summer use because of comfort and possible damage to
temperature-sensitive plants, furniture, or musical instruments.
4.8 INCREASING MAKEUP AIR
Additional negative pressure in basement areas produced by the normal
operation of furnaces can result in increased indoor radon levels. One
approach to controlling this effect is the introduction of makeup air to the
basement or the furnace itself. Several methods of providing makeup air were
tested in house C30A.
43
-------
a
300.0 i
250.0 -
o 200.0-
n
150.0 -I
P
C 100.0 -
1 50.0-
0.0
Date: 5/28
Furnace Off
Closed Doors and
Windows and Turned
Up Heat
Windows Opened
9:30 AM 11:00 AM 12:30 PM 2:00 PM 3:30 PM 5:00 PM 6:30 PM 8:00 PM 9:30 PM
Time
Figure 14. The effect on radon concentration of producing a heat differential
to simulate winter conditions.
44
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TABLE 5. PRESSURE DIFFERENCE MEASUREMENTS FOR TWO HOMES
Condition
House C30A
House closed, outside temperature = 16.6 C (62 F)
inside temperature = 19.4 C (67 F)
Dryer + bath fan on
Furnace + dryer + bath fan on
Furnace +• dryer + bath fan on
inside temperature = 26.7 C (80 F)
0 Pascals
1 Pascals
2 Pascals
3 to 4 Pascals
House C48B
House closed, outside temperature = 16.6 C (62 F)
inside temperature = 17.8 C (64 F)
Furnace on
Furnace on, inside temperature = 33.8 C (92 F)
Furnace on, inside temperature = 33.8 C (92 F)
•*• attic hatch open
Furnace on, inside temperature = 33.8 C (92 F)
+ attic hatch open
0 Pascals
3 Pascals
4 Pascals
5 to 6 Pascals
4 Pascals
45
-------
A fan 2.27 m /h (80 cfm in free air) was used to push air down the thermal
bypass surrounding the chimney. This size fan had an almost imperceptible
impact on the negative pressure between the basement and outside air.
A second effort involved blowing air directly into the basement with a fan
mounted in a basement window. This method was marginally more successful but
required the use of a fan which had to be switched on and off by the home-
owner.
A third method used a 6-inch insulated duct to supply intake air to the
return air plenum of the furnace distribution system. When the furnace blower
was running, about 2.83 m /h (100 cfm) of outside air was introduced into the
34.0 m /h (1,200 cfm) flow in the plenum. The simplicity, effectiveness, and
passive nature of this technique make it preferable over the use of active
methods of supplying makeup air. Active introduction of outside air into a
house may produce excessive basement cooling when operated in the winter;
consequently, the passive technique was adopted for use in the 10 homes when
the reduction of negative pressure using dilution air was required.
46
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5.0 RADON MONITORING
Two radon monitoring techniques were used during this program: continuous
radon monitoring using a Pylon AB-5 monitor together with a passive radon
scintillation cell detector (PRD) (Pylon Model AB-5 & Accessories Instruction
Manual Pylon Instruments, Ottawa, Canada) and an integrating short-term
technique using charcoal canisters (George, 1984). Protocols for the use of
these techniques are detailed in the project Quality Assurance Project Plan
(QAPP) and will not be repeated in this report.
5.1 CONTINUOUS RADON MONITORING
Continuous monitoring results were helpful in understanding the daily
variations in radon concentration in a house and how this pattern, as well as
overall radon levels, were affected by natural and powered ventilation, heat-
ing systems, and other factors that might influence radon levels.
The ability of the passive monitoring system to respond to temporal
variations in radon concentration was tested in the Department of the Energy,
Environmental Measurement Laboratory (EML) exposure chamber. The results 'of
this test are shown in Figures 15 through 18 for each of the PRD scintillation
cells. The lower curve in each of these figures is the radon concentration
recorded by the chamber monitoring devices (four 2-liter active scintillation
cell-based monitors). The upper curve is the response, in counts per minutes
(cpm), of the AB-5 and PRD monitoring system. In all cases, the field moni-
toring device was able to track the laboratory equipment response to concen-
tration changes reliably (on the basis of visual inspection of the super-
imposed curves).
The continuous monitoring system was set to count collected air samples at
30-minute intervals. Three 48-hour sampling periods were used to monitor pre-
and post-radon reduction gas concentrations.
5.2 CHARCOAL CANISTER MONITORING
Short-term integrating monitoring, using activated charcoal monitors, is
the method most commonly used in radon screening and assessment studies. In
47
-------
I
s
IT
56
55 -
54 -
53 -
52 -
51 -
50 -
49 -
48 '
47 -
46 -
45 -
44 -
43 -
42 -
41 -
40 -
39' -
38 '
37
EML Lab 8/14-8/15/86
55
1200
- 50
r 45
u
a
3
- 40
1600
2000
2400
400
800
Time
Figure 15. PRD#123 response to temporal variations.
48
-------
. 55
e
o
o
EM LLab 8/14-8/15/86
1200
800
Figure 16. PRO #124 response to temporal variations.
49
-------
.55
2
ff
1200
1600
2000
2400
400
800
Time
Figure 17. PRO #125 response to temporal variations.
50
-------
I
s
c
§
u
52
51
50
49
48
47
46
45
44 -
43 -
42 -
41 -
40 -
39 -
38 -
37
EM L Lab 8/14-8/15/86
120O
-50
-45
u
a
i
I
h40
1600
2000
2400
400
800
Time
Figure 18. PRO #127 response to temporal variations.
51
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addition, the simplicity and low cost of charcoal canister monitoring made it
an attractive confirmatory measurement technique in the current work. The
canisters and continuous monitoring devices were routinely deployed simul-
taneously in the same locations to allow comparison of monitoring results.
In the Clinton homes, radon concentrations varied by as much as a factor
of 20 in a 24-hour period prior to the installation of radon reduction equip-
ment. Similar wide swings in radon concentration have been observed in other
locations found to be in close proximity to significant soil concentration of
radon. Figure 19 illustrates this phenomenon in house C33C. The ability of
charcoal canisters to provide reliable measurement information under these
conditions is uncertain. George (1984) describes tests of the response by
charcoal canisters to radon concentrations that varied by two times the lowest
concentration during the monitoring period. Analyses of the canisters found
radon concentrations to be representative of the average chamber concentra-
tion. However, no reports of tests at the larger concentration differences
encountered in Clinton were located in a review of the literature.
5.3 MONITORING CONDITIONS
The concentration of radon measured in a house is strongly dependent on
the condition under which the measurement is made. The most reproducible
conditions are those found in winter, when doors and windows are closed for
long periods and thermally driven negative pressure is applied at soil contact
points. A statistical study of available monitoring data conducted by the EPA
found that radon measurement variance was lowest when houses were monitored in
the winter (Ronca-Batista, 1986). This study led to the recommendation that
winter conditions be simulated when monitoring for radon. As discussed in
Section 4 of this report, efforts to simulate winter conditions using a
variety of techniques were at best unreliable.
Radon concentrations in houses show both a daily and seasonal variation.
Measurements were taken within the 2-week period immediately preceding instal-
lation of radon reduction equipment wherever possible. Post-radon reduction
measurements, were made as soon after installation of the radon reduction
equipment as possible. It was hoped that this short time delay between pre-
and post-radon reduction measurements would reduce the effect of seasonal
variation on the measurement; however, in some of the homes requiring three
52
-------
7 -
•• a -
•n O
£ 5 -
3
9
U
§ 2
o *
1 -
Day
Figure 19. Preradon reduction monitoring results. House C33C.
53
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levels of radon reduction, this was not possible. Pre-radon reduction con-
tinuous monitor measurements were made in full summer while post-radon reduc-
tion continuous monitor and charcoal measurements were made under the condi-
tions shown in Figure 19 during the November through January timeframe. In
most cases, baseline data collected under attempted simulated winter con-
ditions did not produce radon levels comparable to those measured during the
DEP radon survey. Initial continuous monitor data were collected when radon
levels were at a seasonal low and the data after radon reduction were col-
lected when indoor radon levels were increasing due to the onset of winter.
Consequently, in some cases, interpretation of radon reduction effectiveness
via continuous monitor data was inconclusive.
5.4 CONTROL HOMES
In an effort to differentiate between random fluctuations in concentration
levels and any real reductions due to the radon reduction efforts, control
homes were selected for simultaneous monitoring with radon reduction demon-
stration homes to be mitigated. Control homes were chosen on the basis of
proximity and similarity in floorplan to the radon reduction demonstration
home. An ideal control home would not receive radon reduction techniques
until work was completed on its corresponding demonstration home. The demon-
stration home would, in addition, have similar baseline radon concentrations
to those found in the corresponding control home. Unfortunately, equipment
and time constraints together with some concern about the high radon exposures
that might occur in control homes where radon has not been reduced led to the
selection of control homes from among the 10 demonstration homes. Conse-
quently, no control home was left in an undisturbed state for the full dura-
tion of the project. Table 6 shows the actual schedule of control home pair-
ings to demonstration homes.
Figure 20 is a log plot showing the before radon reduction measurements on
house C48B and its corresponding control home, house C31B. House C48B was
closed and unoccupied during the first three days of monitoring. For the
remainder of the time it was monitored under normal living conditions. House
C31B was occupied and monitored under normal living conditions for the entire
time period plotted. The pattern of diurnal radon concentration buildup and
decline can be clearly seen in this plot. This phenomenon appears to be
54
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TABLE 6. CONTROL HOMES PAIRED WITH DEMONSTRATION HOMES
House Code
C30A
C31B
C33C
C39A
C46A
C48B
Sample Dates
06/07 to 06/09
06/09 to 06/14
06/27 to 07/02
07/03 to 07/09
08/07 to 08/11
11/17 to 11/20
06/06 to 06/13
06/07 to 06/11
08/07 to 08/13
08/09 to 08/13
08/15 to 08/17
09/21 to 09/24
11/17 to 11/21
06/16 to 06/24
06/19 to 06/22
06/22 to 06/24
09/11 to 09/16
11/17 to 11/20
06/06 to 06/13
06/07 to 06/11
08/09 to 08/12
08/07 to 08/13
09/21 to 09/24
11/04 to 11/12
11/17 to 11/21
06/25 to 07/01
06/25 to 06/27
06/27 to 06/29
07/15 to 07/18
08/07 to 08/09
08/07 to 08/13
11/21 to 11/23
12/09 to 12/11
05/29 to 06/05
05/30 to 06/01
06/01 to 06/04
06/04 to 06/05
07/10 to 07/13
11/07 to 11/20
Control House
C39A
C39A
C46A
C46A
C46A
C39A
C30A
C30A
C30A
C46A
C8A
C39A
C30A
C32D
C32D
C32D
C32D
C32D
C30A
C30A
C30A
C8A
C46A
C48B
C30A
C8A
C8A
C8A
C8A
C39A
C39A
C32D
C24E
C31B
C31B
C31B
C31B
C31B
C31B
(continued'
55
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TABLE 6. CONTROL HOMES PAIRED WITH DEMONSTRATION HOMES (continued)
House Code
Sample Dates
Control House
C24E
08/15 to 08/17
08/17 to 08/19
08/19 to 08/21
12/09 to 12/11
C8A
C8A
C8A
C46A
C8A
06/25 to 07/01
06/25 to 06/27
07/15 to 07/19
08/15 to 08/17
08/19 to 08/21
C46A
C46A
C46A
C24E
C24E
C10B
08/15 to 08/17
08/19 to 08/21
09/14 to 09/17
09/11 to 09/23
C31B
C31B
C31B
C31B
C32D
06/16 to 06/25
06/19 to 06/21
06/21 to 06/24
09/21 to 09/24
11/17 to 11/21
C33C
C33C
C33C
C33C
C33C
56
-------
10,000
1,000
100
1
5:00
prr
5:00=5:00^5:00=5:00=5:00^5:00=5:00=5:00=5:00=5:00^5:00:
"ATI Pfl AM Pf1~~~~AT1PH AM Ptt AH Ptl AM"
5/29 5/30
5/31
6/1
6/2
6/3
6/4
-<> Test Home
Control Home
Time
Figure 20. Premitigation monitoring results for house C48B and control house C31B.
57
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independent of the building structure. The synchronicity of this pattern is
striking and it was repeated throughout demonstration-control home sampling in
Clinton, New Jersey.
Figure 21 is a plot of ambient radon concentration versus time, reproduced
from the report, "Evaluation of Radon Sources and Phosphate Slag in Butte,
Montana" (EPA 1983). The same pattern showing gas concentration peaking near
6 AM, followed by a minimum concentration reached roughly twelve hours later
is seen in outdoor air. This diurnal cycle may be useful in fingerprinting
soil gas radon sources in the diagnostic phases of future radon reduction work
if other sources do not show a similar daily outgassing fluctuation.
58
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5.0 —
4.5
4.0 —<
3.5 —
3.0 —
S. 2.5 H
2.0 —
1.5 —
1.0 -^
0.5
0.0
T f i t i i i i [ i i r T i i t r i i i i i i -r I i r r T
24 6 12 18 24 6 12 18 24 6 12 18 24 6 12 18 24 6 12 18 24 6 12 18 24 6 12 18 24
8/28/80 8/29/80 8/30/80 8/31/80 9/1/80 9/2/80 9/3/80
Figure 21. Ambient radon concentrations, Hebgen Park Monitoring Station, August 8-September 4, 1980.
-------
6.0 DEVELOPMENT OF RADON REDUCTION PLANS
Radon reduction plans were developed for each of the 10 homes based upon
the prior diagnostic assessment, discussions with the homeowners and con-
struction contractor, and available information about effective radon reduc-
tion techniques.
Summary radon reduction plans were prepared for discussion with the home-
owner and construction contractor to describe the installation that would be
necessary. Appendix A includes copies of the radon reduction plans for each
house. The plans included three levels of radon reduction. The first level
was the lowest cost technique considered likely to succeed. Levels two and
three were upgrades from level one. The contractor was to complete level one
before monitoring began. On the basis of post-level one monitoring, a deci-
sion would be made concerning the need for further radon reduction. When
radon concentrations remained elevated, additional diagnostic measurements
were performed to determine the effectiveness of the installation. The second
level of radon reductions was revised based on the results of these diagnostic
measurements. The levels of the radon reduction plan were installed, moni-
tored, and diagnosed in this manner until either the radon concentration was
reduced to an acceptable level or the third level of the plan had been com-
pleted.
Homeowner involvement in the selection, development, and implementation of
the plan was encouraged. A homeowner permission form, reproduced in Appendix
B, was discussed with each of the homeowners before proceeding with the
installation.
Table 7 is a summary matrix showing the important construction features
and the general radon reduction options selected for each of the 10 homes.
60
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TABLE 7. SUMMARY OP RADON REDUCTION PLANS
.
Radon Reduction Method
Perimeter suction
Sump hole suction
Subslnb suction
(exterior)
.Subslab suction
( interior)
Sea) perimeter crack-
no suction on crack
Rerouting, sealing
biibslab ducts, and
applying suction
to the ducts
House Type
Bl-level
(totally finished)
slab below grade
C48B
C10B
C31B
C48B
C31B
C10B
Split level
1/2 basement,
below grade
heating duct
under slab
C39A
C30A
C46A
C8A
C39A
C46A
C8A
C30A
C30A
C39A
C46A
C8A
Two-story,
no baaenent.
subsided
subslab
heating duct
under slab
C33C
C33C
C33C
Two-story, basement
sump hole-drain tile
C32D
C32D
Split level
1/2 slab on grade
earth crawl-space
C24E
(also on block above
footer)
(continued)
-------
TABLE 7. SUMMARY OF RADON REDUCTION PLANS (continued)
Radon Reduction Method
Supplied nakeup air to
furnace (dilution)
Ventilation and isolation
of crawlspace
House Type
Bl-level
totally finished)
slab below grade
Split level
1/2 basement,
below grade
heating duct
under slab
C30A
C46A
C39A
Two-story,
no basement.
subsided
subslab
heating duct
under slab
C33C
Two-story, basement
sump hole-drain tile
Split level
1/2 slab on grade
earth crawl-space
C24E
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7.0 INSTALLATION OF RADON REDUCTION MEASURES
7.1 INSTALLATION MATERIALS
Installation of radon reduction measures in each of the 10 homes followed
the development of radon reduction plans as shown in Appendix A and the
techniques generally documented in the literature. Table 8 is a summary of
principle materials used in the 10 home radon reduction demonstrations.
7.2 ESTIMATE OF INSTALLATION COSTS
Table 9 shows the estimated cost of installation by home. The goal of an
average cost of $2,500 per home was exceeded. This was due primarily to the
cost associated with the radon reduction of house C33C.
Two factors contributed to this large excess. House C33C had essentially
no subslab aggregate. The soil had subsided to from 1 to 4 inches below the
slab. Depressurizing the soil was complicated by the existence of this air
space.
The two highest cost houses shared a common feature—the subslab aggregate
was poor. In the case of C43B, little aggregate was found and airflow from
the central hole punched in the slab was only partially successful. House
C48B had an incomplete foundation in a small crawlspace accessed through the
back of a closet. Radon concentrations in the crawlspace were found to be
elevated. The repair of the foundation was not anticipated in the cost esti-
mate.
Another cause for elevated cost can be attributed to the use of a novel
method of perimeter suction that was used in both house C33C and house C48B
(the second highest cost house). This technique required the labor-intensive
work of cleaning out the perimeter crack and filling it with backer rod and
sealing with pourable polyurethane. The perimeter wall was then ventilated.
The cost of this method was excessive; therefore, other houses, specifically
C10B and C31B, had their radon levels reduced with an alternative, novel
system.
63
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TABLE 8. STANDARD PARTS USED IN INSTALLATION OF RADON REDUCTION SYSTEMS
Duct Fans
Supplier:
RB Kanalflakt Inc.
1121 Lewis Avenue
Sarasota, Florida 33577
(813) 366-7505
Cost: K4 " $ 87 each
K6 " $100 each
* Ducts
- 6 in. oval ducts - exterior - sheet metal
- 6 in. flue ducts (insulated) - ceiling runs (flexduct plastic film inside;
vinyl core)
- 3 in. x 12 in. ducts - ceiling traverses
* Duct Accessories
- 6 in. ceiling diffuser boxes and plates for air outlets
- 4 in. dryer vents with wire mesh screen to direct outlet airflow on
exterior of house
- 4 in. rain cap to cover open exterior ducts
- 4 in. dripless roof flashing to seal around roof exiting ducts
Sealants
Acryl 60 by ThoroSeal for sealing voids-following manufacturer's
instructions, was used for sealing larger openings, such as the cavity
around electrical outlets; sealing voids and cracks-used primarily to
seal dug out perimeter or patching block and slab holes.
To fill dug out perimeter, hardware cloth was rolled and then crushed.
It was placed in the dug out perimeter so that a 5 to 7 cm cavity was
maintained in the crack. The perimeter was then sealed with Acryl 60
cement .
Urethane caulking for general sealing-urethane caulking was used for
sealing around fans, ducts, pipes, and slab penetrations.
-------
TABLE 9. COST OF RADON REDUCTION INSTALLATIONS
(breakdowns by house are estimates)
House Radon
Code Reduction Methods
Labor* Materials
Heating
System** Electrical Total
C30A sump hole suction
sealed subslab
duct suction
sealed perimeter
crack
supplied makeup
air to furnace
2.460
200
490
150 3,300
C39A sealed perimeter
crack
sump hole suction
sealed subslab
duct suction
supplied makeup
air to furnace
1.560
300
490
120 2.470
C8A interior subslab 1,150
suction
sealed perimeter
crack
sealed subslab
duct suction
C46A sealed perimeter 1.700
crack
supplied makeup
air to furnace
interior subslab
suction
C10B exterior subslab 1,040
suction
sealed perimeter
crack
150
490
400
490
400
140 1.930
150 2.740
400 1,840
C31B sealed perimeter
crack
exterior subslab
suction
1,250
400
220 1,870
C48B perimeter suction 3,000 1,000
subslab suction
170
360 4,530
(continued)
65
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TABLE 9. COST OF RADON REDUCTION INSTALLATIONS (continued)
(breakdowns by house are estimates)
House Radon Heating
Code Reduction Methods Labor* Materials System** Electrical Total
C33C perimeter suction 6,650 400 1,310 140 8,500
interior subslab
suction
sealed subslab
duct suction
supplied makeup
air to furnace
C32D sump hole suction 2,860 150 — 170 3,180
interior subslab
suction
C24E interior subslab 900 400 200 1,500
suction _____
ventilation and
isolation of 22,568 3,509 3,453 1,737 31,267.00
crawlspace
* This is only installation cost (subcontractor).
** Rerouting ducts and addition of dilution air.
66
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These two houses had their floor/wall cracks sealed, but the primary radon
reduction technique was applied from the exterior of the houses. Along one
side of the two houses, a trench was dug to the level of the first hollow core
foundation block. Three different penetrations were made in blocks along this
wall. Two penetrations made at the corners of the side wall, entered the void
space in the foundation blocks on the front and rear walls. These penetra-
tions permitted block-wall suction on the front, side, and rear walls. In the
center of the side wall, a penetration was made through the block and into the
loose backfill soil near the floor/wall crack beneath the house floor slab.
By tying all three penetrations along the side wall into a common vertical
plastic vent pipe equipped with an in-line fan, suction could be applied
simultaneously to three walls and the sub-slab. This method was found to be
one of the fastest, least disruptive, and most cost-effective of the methods
used.
A learning curve is evident in the distribution of costs per house.
Houses C30A, C33C, and CA8B were the first three houses where radon reduction
techniques were applied. All subsequent houses show a lower cost for radon
reduction than do these three. The radon reduction plan employed in house
C30A for $3,300 was virtually repeated in houses C8A, CA6A, and C39A at
reductions of $500 or more per house.
House C32D was originally considered to be one of the least costly to
demonstrate radon reduction. Simple sump hole suction and good sealing of
openings and cracks in the basement slab were recommended. When the work was
completed, monitoring indicated that the radon concentration was still
excessive. Measurement of pressure differences between room air and sub-slab
air in the basement showed that suction did not extend to the side of the
house opposite the sump hole. A second sub-slab suction system was installed
to correct this. When monitoring showed that radon levels in the basement had
doubled after installation of the second fan, intensive diagnostic examination
of the basement was begun. Two factors contributed to the elevation in radon
concentration after radon reduction techniques were applied: (1) a tiny fan
leak was allowing radon-rich sub-slab air into the basement and (2) the fan
exhausts on the outside of the house had been placed at ground level allowing
radon-rich air to leak back into the basement. When these two problems were
remedied, basement air radon was significantly reduced.
67
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7.3 DIAGNOSTIC PROCEDURES USED FOLLOWING RADON REDUCTION EFFORTS
Additional diagnostic procedures were required when radon concentrations
were considered to be excessive following the completion of any radon reduc-
tion plan level. Initially, diagnostic procedures focused on the function of
the installed system checking ducts, fan, seals, and airflow through the
system. If elevated radon concentrations could not be linked to a failure or
weakness in the installed system, post-diagnostic procedures were directed
toward the identification of secondary fadon routes that may have been missed
during earlier inspections. This process involved a repetition of the basic
pre-radon reduction diagnostic efforts.
In many cases, secondary sources of radon infiltration were discovered and
the subsequent radon reduction plan level was re-evaluated. In some cases,
particularly in homes with finished basements or slab-on-grade levels, no
secondary sources were located, and installed soil depressurization systems
were functioning to specifications. In these cases, the addition of dilution
air was required to produce any further reduction in radon concentration.
68
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8.0 QUALITY ASSURANCE
The Quality Assurance Project Plan (QAPP) dated June 11, 1986, was
approved by the AEERL Project Officer and Quality Assurance Officer prior to
initiation of data-gathering activities. The objective of this project was to
demonstrate radon reduction by use of low-cost mitigation techniques in up to
ten homes. Charcoal canister and passive scintillation cell measurement meth-
ods were identified as the methods of choice for determining the extent of
radon reduction in the homes. Data quality objectives (DQOs) for the quality
of these two methods were established in the approved QAPP. The DQOs are
shown in Table 10.
Precision, accuracy, and completeness objectives were met for measure-
ments made using charcoal canisters and passive scintillation cell radon moni-
tors. Tables 11 and 12 show the actual performance with respect to the DQOs.
Details are provided in Sections 8.1 and 8.2. Sections 8.3 through 8.5 detail
other QA information including results of audits, the impact of seasons on
radon concentration, and the use of control homes.
8.1 QUALITY ASSURANCE OBJECTIVES FOR PASSIVE SCINTILLATION CELL RADON
MONITORING
Four Pylon AB-5 radon monitors fitted with Pylon passive radon detector
cells were used in the course of the project. Protocols detailed in the QAPP
were followed at all times. Monitoring is discussed in Section 6 of this
report.
The instruments were calibrated in the radon chamber at the EML twice
during the project. Two of the monitoring systems were used only for post-
radon reduction sampling and were calibrated once during the course of the
project. The calibration procedure is described in the QAPP. Figures 22
through 25 show the calibration curves for the four devices. Table 11 shows
the calibration constants and a calculation constant over the period between
calibrations. Accuracy is calculated to be well within the objective of *20
percent bias.
This measurement technique relies on the counting of radon events (alpha
particle scintillations) and can therefore be described by Poisson statistics.
69
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TABLE 10. QUALITY ASSURANCE OBJECTIVES
Precision Accuracy
Measurement Method Conditions (RSD) (Percent Bias) Completeness
Passive scintillation cell radon indoor atmospheres (living 20% +/- 20* 90*
monitor conditions pre- and post-
radon reduction)
Charcoal canisters indoor atmospheres (living 10% +/- 10* 90*
conditions pre- and post-
radon reduction)
-------
TABLE 11. PASSIVE SCINTILLATION CELL RADON MONITOR CALIBRATION CONSTANTS
Calibration:
6/4 to 6/5/86 8/14 to 8/15/86
Equipment ID*
(Correction factor: '
pCi/1
Percent Bias
AB-5
PRO
PRO
AB-5
PRO
PRO
AB-5
PRO
AB-5
PRO
#250
#123 1.270
#124 1.197
#244 1.278
#125 1.204
#123
#255 not in use
#125 1.117
#258 not in use
#127 1.116
5.7*
5.8*
n/a
n/a
71
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TABLE 12. CHARCOAL CANISTER QUALITY ASSURANCE SAMPLES
Number of
samples
Concentrat ion
(PCI/1)
Blanks
6
1) 6 days d.l. = 4 pCi/1.
** These RSD values are for two "spiked" samples colocated in the chamber.
-------
a
u
55
54 -
53 -
52 -
51 -
50 -
49 -
48 -
47 -
46 -
45 -
44
EML Lab 3/14-8/15/86
37
Slope - 1.197 cpm/pCi/l
R2 - 0.82
39
41 43
Radon Concentration (pCi/1).
45
47
Figure 22. Calibration data: AB-5 #250, PRO #124.
73
-------
IB
ec
56
55 -
54 -
53 -
52 -
51 -
50 -
49 -
48 -
47 -
46 -
45 -
44 -
43
EML Lab 8/14-3/15/86
37
S1ope-1.204cpm/pCi/l
R2 - 0.735
39
41 43
Radon Concentration (pCi/l)
45
Figure 23. Calibration data: AB-5 #244, PRO #123.
47
74
-------
a
u
10
tr
*•
3
EML Lab 8/14-8/15/86
Slope - 1.117 cpm/pCi/I
37
39
41 43
Radon Concentration (pCi/I)
45
Figure 24. Calibration data: AB-5 #255, PRO #125.
75
-------
52
51 -
50 -
49 -
a.
u
I47'
**
I46'
45 -
44 .
43 -
42
EML Lab 8/14-3/15/86
37
Slope - 1.116 cpm/pCi/1
R2 - 0.72
( 1
41
39 41 43 45
Radon Concentration (pCi/1)
Figure 25. Calibration data: AB-5 #258, PRO #127.
47
76
-------
For a Poisson distribution, the variance of a population is equal to the mean
of that population. If single measurements are made from a Poisson distri-
bution, then it must be assumed that the measured value is the mean of the
distribution. By the nature of Poisson distributions, the precision of such a
measurement will be determined by the size of the population. Specifically,
the precision of measurement will be equal to the standard deviation for the
measured value, which can best be described as the square root of the mean
value. As a result, precision of a measurement can be fixed by specifying a
minimum count. To maintain a precision of +20 percent, a count of at least 25
is necessary. The sample duration of 30 minutes used in all field measure-
ments ensured that this minimum count was down to a concentration of less than
1 pCi/1 for calibration factors that are greater than 1 cpm/pCi/1. Because
the critical guidance level for action on radon-contaminated homes is A pCi/1,
the precision goal was met at all times during sampling.
The QAPP called for a minimum of one pre-radon reduction sampling period
consisting of three 48-hour sampling periods and a second post-radon reduction
sampling period of the same duration. This minimum was met in the case of all
but house C24E. Since completeness was 90 percent, the quality assurance goal
for this measurement technique was achieved.
8.2 QUALITY ASSURANCE OBJECTIVES FOR CHARCOAL CANISTERS
Charcoal canister sampling and analysis were completed following pro-
cedures prescribed in the QAPP- Table 12 details quality control and assur-
ance samples collected using this technique.
Overall precision and completeness goals were met. However, accuracy
goals were not met in the case of one set of three simultaneously chamber-
exposed canisters. In investigating the reason for the large negative bias in
these canisters, it was found that the analytical laboratory determined the
relative humidity based upon the charcoal weight gain to have been approxi-
mately half of the chamber recorder value, 68 percent. Some loose charcoal
was reported when the canisters were returned from the exposure chamber, and
charcoal loss would reduce the weight of the canister and mask the effect of
adsorbed water vapor. Since quality assurance samples were handled in the
same way, a similar bias might occur in some of the field samples due to loss
of charcoal. However, when charcoal canister results are compared to continu-
ous monitoring results, no clear bias is seen. When the concentrations deter-
mined by the analytical laboratory were recalculated using the actual chamber
77
-------
relative humidity, accuracy for the technique was well within the quality
assurance goals for the project.
8.3 SYSTEMS AUDITS
An audit of project records was conducted by Keith Daum (RTI) during July
1986. Five sets of records were reviewed, namely: field notebooks (house
sections), house files, instrument log, sample log, and pre-selection check-
lists. No major deficiencies were identified by the audit. Mr. Daum did
identify some minor inconsistencies in the notebooks and files which were
corrected following this audit. These corrections included:
• Floorplans drawn in the notebooks are now identified as soil
contact floors.
• All pages of graphed data are now dated.
• All manual calculations were checked and the pages were
initialed.
• A project decision was made to discontinue pre-radon reduction
alpha-track monitoring so Mr. Damn's comments on these entries
were not addressed.
As a follow-on to Mr. Damn's audit, a review was conducted onsite at the
end of September by Ms. Judy Ford, Quality Assurance Officer for AEERL, RTF,
and Mr. Michael Messner, the RTI project Quality Assurance Officer. The
reviewers determined that approved quality assurance procedures were being
followed and that minor recordkeeping inconsistencies had been corrected.
8.4 SEASONAL INDOOR RADON VARIATIONS
The factor having the greatest impact on the assessment of radon reduction
technique effectiveness is the lack of information concerning the seasonal
indoor radon variations in the Clinton area. Sampling results, discussed
elsewhere in this report show that radon concentrations tend to increase sig-
nificantly during the heating season, even if summer-collected samples are
taken following the EPA-prescribed procedures with the house completely
closed. Efforts to simulate winter conditions (as discussed in Section 4)
showed variable success. In two cases, measurements matched the levels of
radon recorded by the New Jersey DEP in their March and April screening study.
Because pre-radon reduction sampling was done in early summer, when levels
78
-------
were expected to be at their lowest, and post-radon reduction sampling was
completed in December, direct comparison of pre- and post-radon reduction
monitoring results are misleading. Table 13 shows estimates of the maximum
and minimum possible reductions. Minimum reductions were similarly calculated
subtracting results of post-radon reduction canister monitoring from the pre-
radon reduction closed house charcoal canister results. Maximum post-radon
reduction calculations were made using the difference between the New Jersey
DEP collected data and post-radon reduction monitoring results. In the worst
case, radon reduction rates ranged from 0 to 97.6 percent (house C10B) and in
the best case, from 99.7 to 99.8 percent (house C30A). Because minimum reduc-
tions are based on pre- and post-radon reduction canister results, the accu-
racy (bias) of the canister measurements is not a factor. Under these circum-
stances, the accuracy achieved in charcoal canister sampling was more than
sufficient to meet the project goals.
8.5 CONTROL HOMES
Control homes were selected for simultaneous sampling from among the 10
homes involved in the demonstration work. Consequently, control homes for
post-radon reduction sampling were often houses where radon had already been
reduced. There is some evidence that installation of radon reduction techni-
ques will affect not only the radon level but the daily pattern of radon
buildup on a home (NYSERDA, 1986), making homes where radon has not been
reduced the preferred controls. In this project it was necessary to use 10
demonstration homes also as control homes because of the time schedule and
available equipment.
79
-------
TABLE 13. APPROXIMATE REDUCTION IN RADON CONCENTRATION USING CHARCOAL CANISTER DATA
FOLLOWING APPLICATION OF RADON REDUCTION TECHNIQUES
(pCi/1)
Before
Radon Reduction
(Early Spring)
House Code (DEP)*
A8
A46
BIO
791
635
418
Before
Radon Reduction
(Summer)
(Closed House)
After
Radon Reduction**
(Late Fall)
(Closed House)
Minimum Maximum
Percent Percent
Reduction Reduction
A30
A39
2,254
1.500
1,450
10.4
4.1
4.3
99.7
58.7
99.8
99.7
(1,250 w/Pylon)
409
772
15.8
(70 w/Pylon)
2.9
9.0
16.0
99.3
98.8
0
99.6
99.2
97.6
B31
848
C33
D32
E24
691
936
1,190
1,357
426
89.0
771
304
29.0
(130 w/Pylon)
91.0
(210 w/Pylon)
5.8
11.1
4.7
11.3
12.3
93.5
98.6
98.5
61.0
86.5
99.2
98.8
99.7
99.2
97.2
* DEP screening study charcoal canister measurements taken in March and April of
1986.
** Highest post-radon reduction charcoal canister measurements taken in August 1985
through January 1986.
80
-------
9.0 RESULTS AND CONCLUSIONS
Figures 26 through 35 plot before and after radon reduction continuous
monitoring results for each of the 10 homes. Results of the highest before
radon reduction charcoal canister monitoring (including DEP screening results)
and the last before radon reduction charcoal canister monitoring are also
shown on these plots. Table 14 is a complete listing of charcoal canister
monitoring results for the 10 homes.
9.1 HOUSE C8A
Monitoring results from house C8A are shown in Figure 26. This is a
split-level house that had a finished basement with bedroom space in the
basement. Radon reduction results were highly satisfactory and a reduction in
average radon concentration by any measure was large. The cost associated
with this house was slightly higher than average due to the need to route duct
work through the finished portions of the house.
9.2 HOUSE C30A
Figure 27 shows the monitoring results for this split-level house. House
C30A received radon reducing measures early in the project and the reduction
plan was copied in the other A-floor plan homes, obtaining substantial reduc-
tions in all cases. The C30A homeowners preferred to keep their house very
warm in the winter and extra attic insulation was noted during pre-radon
reduction inspections. Consequently, to prevent an excessive stack effect a
passive makeup air duct was connected from the outside of the house to the
furnace return duct which provided dilution air without cooling the house
excessively. The dilution air will be introduced only when the furnace is
running.
9.3 HOUSE C39A
Figure 28 shows the results of monitoring in this split-level house.
Estimation of real reductions in this house was complicated by the lack of
success in simulating winter conditions during pre-radon reduction sampling.
-------
10,000
1,000 -
100-
10 -
1 -
O.T
NJDEP
Post-RR
Day Number
Note: NJ DEP measurements were made using homeowner-located charcoal
canister monitoring devices.
Pre-RR refers to Pre-Radon Reduction measurements
Post-RR refers to Post-Radon Reduction measurements
CC refers to RTI Charcoal Canister measurements.
Figure 26. House C8A: pre- and post-radon reductions results.
82
-------
10,000 -
NJDEP
1.000,
-s 100 -
-------
3
w
O>
o
o
Q.
3.6
3.4
3~.2
3.0
2.8
2.6
2.4
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
0.5
1.5
2.5
Day Number
3.5
4.5
Figure 28. House C39A: pre- and post-radon reduction results.
84
-------
10,000
1,000 .
e> 100
o
o
a
10 -
NJDEP
Pre-RR
2 4
Day Number
— CC
Figure 29. House C46A: pre- and post-radon reduction results.
85
-------
Day Number
Figure 30. House C10B: pre- and post-radon reduction results.
86
-------
10,000
1.000 _
100 -
10 -
1 -
0.1 -
Day Number
Figure 31. House C31B: pre- and post-radon reduction results.
87
-------
10,000-
1.000-
NJDEP
100-
o
a
1 -
0.1
I I
Day Number
Figure 32. House C48B: pre- and post-mitigation results.
88
-------
10.000'
Figure 33. House C33C: pre- and post-radon reduction results.
89
-------
50
45 -
40 -
35- -
- 30-
u
a
7 25 -
o
*-
I 20 -
S
I 15-
10 -
5 -
NJOEP
Post-RR
0 +-
0
—i 1 r
2 3
Day Number
"AT/00
n/
Figure 34. House C32D: pre- and post-radon reduction results.
90
-------
210
Figure 35. House C24E: pre- and post-radon reduction results.
91
-------
TABLE 14. RADON CONCENTRATIONS AS DETERMINED WITH CHARCOAL CANISTERS
House code
C30A
Before
After
C31B
Before
After
C33C
Before
After
C39A
Before
After
Sample date
4/7
6/7 to 6/9
6/9 to 6/14
6/27 to 7/2
6/27 to 7/2
7/3 to 7/5
7/5 to 7/7
7/7 to 7/9
11/17 to 11/20
3/22
5/28 to 6/1
6/1 to 6/4
8/15 to 8/17
8/15 to 8/21
8/19 to 8/21
9/11 to
9/11 to
11/17 to 11/20
3/15
6/22 to 6/24
7/23 to 7/25
7/25 to 7/27
7/27 to 8/1
10/4 to 10/10
10/4 to 10/10
11/17 to 11/20
11/17 to 11/20
4/7
8/19 to
9/21 to
6/7 to 6/11
11/17 to 11/20
Concentration (pCi/1)
2,254
1,450
498
2
4
3.5
2.4
3.4
4.1
691
8.2
4.4
89
76.6
1.3
4.0
4.0
5.8
1,190
304.2
8
106
8.7
8.5
5.8
4.7
4.7
1,523
7.5
8.3
10.4
4.3
Comments
early spring
closed house
dining room
early spring
house closed
with heat on
late winter
living room
small bedroom
furnace room
living room
living room
early spring
basement
( continued)
92
-------
TABLE 14. RADON CONCENTRATIONS AS DETERMINED WITH CHARCOAL CANISTERS
(continued)
House code
Sample date
Concentration (pCi/1)
Comments
C46A
Before
After
C48B
Before
After
C24E
Before
After
C8A
Before
After
4/7
6/25 to 6/27
6/27 to 6/29
7/31 to
8/7 to 8/9
12/9 to 12/11
1/3/87 to 1/5/87
4/7
5/30 to 6/1
6/1 to 6/4
6/4 to 6/5
11/17 to 11/20
12/9 to 12/11
4/16
8/15 to 8/17
8/17 to 8/19
8/19 to 8/21
9/25 to 9/30
12/9 to 12/11
12/9 to 12/11
3/22
6/25 to 6/27
6/27 to 7/1
7/31 to
8/15 to 8/17
8/17 to 8/19
8/19 to 8/21
11/17 to 11/20
635
771.9
433
157
238.5
5.3
9.0
936
771.9
37.6
4
12
11.1
426
90.9
2.5
1.3
3.0
7.2
12.3
791
409.2
241
3
5
4.2
2.8
2.9
early spring
basement
early spring
basement
heat on
early spring
house closed
downstairs
living room
early spring
house closed
[continued)
93
-------
TABLE 14. RADON CONCENTRATIONS AS DETERMINED WITH CHARCOAL CANISTERS
(continued)
House code
Sample date
Concentration (pCi/1)
Comments
C10B
Before
4/18
8/15 to 8/17
8/17 to 8/19
8/17 to 8/19
8/17 to 8/19
418
15.8
9.8
4.2
2.5
early spring
After
9/11 to 9/16
11/17 to 11/19
4.0
16.12
heat on
C32D
Before
After
3/22
6/19 to 6/21
6/21 to 6/24
9/21 to 9/26
11/17 to 11/20
12/9 to 12/11
12/9 to 12/11
1,357
29.1
7.2
20.1
8
5.1
11.3
early spring
family room
basement
94
-------
In addition, post-radon reduction monitoring only covered a 3-day period.
However, both the before- and after-radon reduction changes shown by the
charcoal canister results and the averages of the continuous monitoring
results suggest substantial reductions were made. In this home, a passive
dilution air system was attached to the furnace air handler similar to house
C30A. The same techniques used in the other A-floor plan homes was used in
this home.
9.4 HOUSE CA6A
Monitoring results for this split-level house shown in Figure 29 indicate
two levels of radon reduction. The first level "shows the monitoring results
with two smaller sized fans in place. The second shows the effect of upgrad-
ing the fans to the next largest fan size. Since this home was generally kept
warm, dilution air was added to the furnace air handler. The post-radon
reduction charcoal canister results shown on this plot were taken in January
when demand on the passive system would be supplying dilution air to the
hous e.
9.5 HOUSE C10B
Figure 30 shows the results of monitoring in this bi-level home. Inter-
pretation of the results are difficult due to the low pre-radon reduction
continuous monitor concentrations measured. In this home, because of active
occupants and a continuously occupied house, full closed house conditions were
not maintained. The radon reduction plan for this home took into account the
very high usage of space and the active life of the family occupying the
house. Consequently, the radon reduction plan called for an outside radon
reduction system that would involve a minimum of disruption in the house. The
fan and all the ductwork were outside of the house. An electrical code re-
quirement included a cutoff switch on the outdoor system; therefore, a warning
light was wired inside the house to show when the fan had been cut off allow-
ing the homeowner to reactivate the system. The middle charcoal canister line
on this plot shows the increased radon concentrations in this house due to
winter conditions. This home may be a candidate for the addition of a passive
fresh air vent to the furnace air handler to provide dilution air to the house
in the winter.
95
-------
9.6 HOUSE C31B
This bi-level house was continuously occupied with four small children.
The same approach that was taken with house C10B was applied to this home.
Figure 31 shows the monitoring results for this bi-level home. Again, winter
monitoring may show that this house requires the addition of a passive fresh
air vent to the furnace to provide dilution air during winter-time conditions.
9.7 HOUSE C48B
House C48B shown in Figure 32 was the first of the B-floor plans to re-
ceive radon reduction techniques. The techniques attempted in this bi-level
home proved to be both more costly and less effective than the outdoor methods
used in the other two B-floor plan homes. Subslab suction was installed using
one hole drilled through the slab in the furnace room. A tunnel was dug out
for approximately 1 meter (3.3 ft) out from the hole, under the slab. The
subslab aggregate was insufficient to provide adequate subslab suction. Con-
sequently, a labor intensive method of creating perimeter suction was at-
tempted. This method was partially successful in further reducing the indoor
radon levels. Finally, an unfinished portion of the foundation behind the
earth filled front steps was repaired to prevent exposed earth contact with .
living space air.
9.8 HOUSE C33C
Results of monitoring in this slab-on-grade house are shown in Figure 33.
This house was the most difficult of the 10 demonstration homes to achieve
reduced radon levels. The subslab ducts had to be rerouted between the two
floors of the house requiring considerable repair of finished space. No
subslab aggregate was present and the earth had subsided under the slab leav-
ing a substantial air space. Through perimeter suction, rerouting and sealing
of subslab ducts, and a passive fresh air vent system to the furnace, signifi-
cant radon reductions were achieved in this house.
9.9 HOUSE C32D
Radon reduction in this block-basement home involved sump hole suction, a.
secondary sub-slab suction at the opposite end from the basement of the sump
hole, and extensive sealing. After application of radon reducing techniques
difficulties were encountered due to the placement of fan exhausts at ground
96
-------
level where radon-rich air was permitted to leak back into the basement.
Figure 34 shows the large radon reductions that were achieved in this house.
9.10 HOUSE C24E
House C24E was the only home selected that was not built by the subdivi-
sion developer and the only home with a crawlspace. In this split-level home,
the crawlspace had earth exposure and a doorway which opened on to the lowest
level of the house. Radon reduction in this home concentrated on isolating
and ventilating the crawlspace. Figure 35 shows the results of this radon
reduction effort. Due to the project time constraints continuous monitoring
results were not collected for the period following radon reduction.
97
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10.0 RECOMMENDATIONS
A database of all homes receiving the application of radon reduction
techniques in Clinton Knoll should be maintained and analyzed. The
database should contain pre- and post-radon reduction radon levels.
A summary of the radon reduction method used, the house floorplan
and any unusual features of the house or the property on which it is
built should be included.
Long-term followup monitoring should be carried out in each of the
mitigated homes to determine the average annual radon levels. This
monitoring should be carried out for a period of at least two years
and should include continuous monitoring for a period of 1 week in
each season in an effort to identify seasonal effects on the radon
concentrations in the homes and peak exposures.
In future radon reduction projects at least 1 control home for each
10 demonstration homes should be monitored continuously during the
entire period that radon reduction work and monitoring is being
done. The control home should not be subjected to radon reduction
methods during this time.
Investigation into the mechanisms controlling the strong diurnal
variation in radon concentration in indoor air should be pursued.
If periods of high radon levels during the day can be reliably
predicted, radon reduction techniques could be directed toward
reducing or eliminating those peaks.
98
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REFERENCES
Benton, 1981
Benton, E. V., R. Oswald, and A. Frank, "Proton Recoil Neutron Dosimeter for
Personnel Monitoring," Health Physics, Vol. 40, pp. 801-809, June 1981.
EPA, 1978
U. S. Environmental Protection Agency, Office of Radiation Programs, "The
Effects of Home Ventilation Systems on Indoor Radon-Radon Daughter
Levels," EPA-520/5-77-011, (NTIS PB291925), October 1978.
EPA, 1983
U. S. Environmental Protection Agency, "Evaluation of Radon Sources and Phos-
phate Slag in Butte, Montana," Office of Radiation Programs.
EPA, 1986a
U. S. Environmental Protection Agency, "A Citizen's Guide to Radon: What It
Is and What To Do About It," OPA-86-004, August 1986.
EPA, 1986b
D. S. Environmental Protection Agency, "Radon Reduction Methods: A Home-
owner's Guide," OPA-86-005, August 1986.
EPA, 1986c
U. S. Environmental Protection Agency, Office of Radiation Programs, "Interim
Indoor Radon and Radon Decay Product Measurement Protocols," EPA-520/
1-86-04, February 1986. ' .
EPA, 1986d
U. S. Environmental Protection Agency, "Radon Reduction Techniques for
Detached Houses: Technical Guidance,"•Office of Research and Develop-
ment, Washington, D. C., EPA/625/5-86/019, June 1986.
George, 1984
George, A. C., "Passive Integrated Measurement of Indoor Radon Using Activated
Carbon," Health Physics, Vol. 46, No.4 4, pp. 867-872, 1984.
Henschel, 1986
Henschel, B., A. Scott, "The EPA Program to Demonstrate Mitigation Measures
for Indoor Radon: Initial Results," Proceedings, Indoor Radon, APCA
Specialty Conference, Philadelphia, 1986.
Kronval, 1980
Kronval, J., "Correlating Pressurization and Infiltration Rate Data Tests of
Heuristic Model," Lund Institute of Technology, Division of Building
Technology, Lund, Sweden.
Sherman, 1980
Sherman, M. "Air Infiltration in Buildings," Ph.D. thesis, report No. 10712,
Lawrence Berkeley Laboratory, University of California, 1980.
99
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Nazaroff, 1985
Nazaroff, W. W., H. Feustel, A. V. Aero, K. L. Revzan, D. T. Grimsrud, M. A.
Essling, and R. E. Toohey, "Radon Transport Into a Detached One-Story
House with a Basement," Atmospheric Environment, Vol. 19, No. 1,
pp. 31-46, 1985.
Nitschke, 1986
Nitschke, I., T. Brennan, J. Wadach, and R. O'Neil, "The Radon House Doctor,"
Indoor Radon, APCA Specialty Conference, Philadelphia, 1986.
NYSERDA, 1985
N. Y. State Energy Research and Development Authority, "Indoor Air Quality,
Infiltration, and Ventilation in Residential Building," Report 85-10,
March 1985.
Ronca-Battista, 1986
Ronca-Battista, M., and S. Windham, "Uncertainties of Estimating Average Radon
and Radon Decay Product Concentrations in Occupied Houses," Proceedings,
Indoor Radon, APCA Specialty Conference, Philadelphia, 1986.
Shaw, 1981
Shaw, J. , "A Correlation Between Air Infiltration and Air Tightness for Houses
in a Developed Residential Area," ASHRAE Transactions, 1981, Vol. 87,
Part 2, pp. 333-341.
Turk, 1986
Turk, B. H., R. J. Prell, W. J. Fisk, D. T. Grimsrud, B. A. Moed, and R. G.
Sextro, "Radon and Remedial Action in Spokane River Valley Residences:
An Interim Report," Draft Report, Department of Energy Contract No.
DE-AC03-76SF00098 [no final report intended].
100
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APPENDIX A
RADON REDUCTION PLANS
Page
House Code: C8A A2
House Code: C30A A8
House Code : C39A A15
House Code: C46A A23
House Code: C10B A30
House Code: C31B A34
House Code: C48B A40
House Code: C33C A46
House Code: C32D A53
House Code : C24E A59
A-i
-------
House Code: C8A
A-l
-------
REPORT ON MEASUREMENTS AND RADON REDUCTION PLAN
HOUSE CODE: C8A
DESCRIPTION: C8A is a classic split level with a finished half basement. The
basement is divided into three rooms . the largest of which is a family room.
One room is used as a child's bedroom, and the third room is used as a
storage/workshop area and houses the furnace.
DIAGNOSTIC INVESTIGATION: A substantial leak of radon was found in a transite
pipe in the bedroom showing a canister concentration of 1600 pCi/1. A
scintillation cell grab sample was taken from electrical outlet in the block
wall and showed a concentration of 1700 pCi/1. Pressure dry and blower door
measurements were taken. The plumbing chase was considered a good option for
suction fan ductwork to the attic. A hole was drilled In the slab and sub-
slab pebbles were found to a depth of 3-4 inches.
BEFORE RADON REDUCTION
a) CHARCOAL CANISTERS
EARLY SPRING CONCENTRATION:(State of New Jersey): 791 pCi/1
DATE LOCATION CONCENTRATION
(pCi/1)
6/25 to 6/27 On bar in basement 409
(house closed)
6/27 to 7/1 On bar in basement 241
(house open)
A-2
-------
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
6/25 to 7/1
7/15 to 7/18
On bar in basement
(house closed )
On bar in basement
'450 avg.
'720 max.
'3.5 avg.
'13 max.
a) CHARCOAL CANISTERS
AFTER RADON REDUCTION
DATE
LOCATION
CONCENTRATION
(PCI/1)
7/31
8/15
8/17
8/18
11/17
to
to
to
to
to
8/2
8/17
8/19
8/21
11/20
On bar in basement
same
same
same
same-heat on
3
5
4
2.
2
.8
.9
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCl/1)
8/15 to 8/21
On bar in basement
(house closed )
"0 min.
12 max.
*4 avg.
A-3
-------
If A It
A" Floorplan
Kitchen
Lav
Family
Room
Down
Bedroom
Dining Room
li
0
New Heating Supply Ducts
Master
Bedroom
thru closet
Down
Living Room
nT
CT.
c
»T.
Duct thru Closet'
Bedroom
•To fans in attic.
', 1
: P
•; ' ;•;•
. . • . Floor Grills Sealed
Slab on Grade
./*
i 1M
i
'
J-
y
Basement
\U\ Chimney
H Up
Sub Slab Ventilation Du
\
L
Sump Hole
rt
I
\n
•
f
-
Footer Drains
A-4
-------
RADON REDUCTION PLAN
House Code: CAS
Phase I
Basement Area
Since this house has a finished basement, special effort will be made to
cover or enclose duct and pipe work.
1. Seal sub-slab heating ducts.
2. Seal wall and floor crack penetrations (several large openings around
existing ducts).
3. Punch hole in floor of furnace room and evacuate.
a. exhaust pipe to exit building via roof.
Slab-on-Grade Area
1. Seal and depressurize sub-slab ductwork.
a. drill openings "1.3 cm ("1/2") through transite duct where access
allows. EPA Guidelines should be followed for this activity.
2. run new heating ducts to the kitchen and living room area.
Phase II
Basement Area
1. Ventilate block wall either actively or passively.
Slab on Grade Area
1. Seal perimeter crack at slab-block intersection being careful to allow for
active or passive ventilation of the perimeter crack at a later date.
A-5
-------
HOUSE TESTS
House C8A
(4/30/Bfi|
(ft!
Temperature Temperature Barometric
In out pressure Correlation
'C I'M 'C CFI Pascals coefficient
Effective
Leakage Area
ACII at (I.HI. Method)
50 Pascals cm^ (square inches)
Equivalent
Leakiige Area
(Canadian Method)
c«' (square Inches I
iMsencnl
fill
(21 .
Uasc
6)1
(21 .
Undo
6)1
(21 .
.6
600)
•lent
.6
600)
door
.6
600)
door open : * ' '
21
(70) 21 (701 30.00 0.999 420 0.533 9.40
1 . 608 .
(249.
7
35)
2.719
(421
4
.51)
door closed: ' ^1
21
closed
21
(70) 21 (70) 30.00 0.985 357.50 0.533 8.01
: (3)
170) 21 (70) 30.00 0.998 353.93 0.544 8.26
1.369.
(212.
1.375
(2)3
7
30)
.5
21)
2.315
(358
2.347
(363
.6
.92)
.7
.89)
41* •* 1
HOUSE FUSSUKE if»*cm
I -
4 u> n •>
uoust russuu (F..C.I.)
(I)
-------
House Code: C30A
A-7
-------
REPORT ON MEASUREMENTS AND RADON REDUCTION PLAN
HOUSE CODE: C30A
DESCRIPTION: This is a split-level house with an unfinished half-basement.
An enclosed patio was added to the back of the house behind the family room.
The residents prefer their home to be very warm (about 24'C, 75°F), and heavy
insulation was found in the attic.
DIAGNOSTIC INVESTIGATION: Leakage was found at the uncapped block tops and
in the space around the utility meter window. A major crack below grade was
located on the front wall of the house and a baseball-sized hole was located
between the internal basement wall and the back wall of the house. Upstairs,
further leakage was found around the kitchen and bathroom. Access to the
attic is through the garage. Chimney stack to the basement was located in the
plumbing chase. The force air heating ducts ran under the slab. Grab sample
measurement of air in these ducts showed concentrations as high as 53.000
pCi/1. Concentrations in the drain tile around the sump were 36,000 pCi/1 and
in the sump hole itself they were 2100 pCi/1.
BEFORE RADON REDUCTION
a) CHARCOAL CANISTERS
-LATE SPRING CONCENTRATION:(State of New Jersey): 2254 pCi/1
DATE LOCATION CONCENTRATION
(pCi/1)
6/7 to 6/9 basement-house closed 1450
6/9 to 6/14 basement 498
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE LOCATION CONCENTRATION
(pCi/1)
6/6 to 6/13 Basement max. " 2600
min. ' 75
A-8
-------
AFTER RADON REDUCTION
a) CHARCOAL CANISTERS
DATE LOCATION CONCENTRATION
(pCi/1)
6/27 to 7/2
6/27 to 7/2
7/3 to 7/5
7/5 to 7/7
7/7 to 7/9
11/17 to 11/20
dining room 2
4
3.
2.
3.
4.
5
4
4
1
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE LOCATION CONCENTRATION
(pCi/1)
6/26 to 6/27 basement max " 8
level I radon min " 0
reduction
plan
7/3 to 7/10 basement max " 20
level II radon min " 2
reduction
plan
8/7 to 8/3 basement max " 20
min " 0
A-9
-------
11,11
A" Floorplan
Kitchen
Lav
Family
Room
Down
Bedroom
Dining Room
New Heating Supply Ducts
Master
Bedroom
Duct thru closet
Down
Living Room
• T c T. c •
1 r '<= «
Duct thru Closet'
Bedroom
*To fans in attic.
1
: |
Basement
-T-I-T— I !*i Chimney
* -Up
Floor Grills Sealed
Slab on Grade
I
Sub Slab Ventilation Duct ;'
Sump Hole 1 •{
Footer Drains
A-10
-------
RADON REDUCTION PLAN
House Code: C30A
Phase I
Basement Area
1. Seal and evacuate sump hole (see attached diagram).
(a) exhaust pipe to exit building through roof with care taken to
minimize visual impact on living areas
2. Seal wall and floor cracks and penetrations
(specifically seal open block tops on each side of basement window,
at corner where slab level attaches to basement wall and other
locations where open blocks are found during site inspection.
3. Supply makeup combustion air to furnace area (passively)
Slab-on-Grade Area
1. Seal and depressurize sub-slab duct work
(a) drill openings ("1/2") through transit duct where access allows. EPA
guidelines should be followed for this activity.
2. Run new heating ducts to the kitchen and living room area.
3. Seal perimeter crack at slab-block intersection being careful to do it in
such a way as to allow future active or passive ventilation of the
perimeter crack at a later date.
A-ll
-------
Mop Board
Expansion Joint
(With Homosote F1
Concrete Slab
Sheetrock
Earth Fill
Scale
\- = r
Pipe To Outside
Fan
4" PVC Pipe
Galvanized Cover
Slab
Sump Hole
'2 Stone
1/2" Plywood
2x4 Stud Wall
2x4 Sill
Solid L - Block
8" Concrete Block
(Hollow Core)
J
Block Wall
Clay Weeping Tile
A-12
-------
IIODSK TKSTS
llouau C30A
(4/30/B(i|
Ti-«|jei aim c Te>perature Baroaetrlc
Vuliix: In (ml pressure Correlation
•3 (fi3) 'C CM *C CFI Pascals coefficient
ll.isi.-mont door cloned: '''
•107. B 21 (70) 21 (70) 30.00 0.993
( 14 .400)
( refer to gruuh (2) )
611 6 21 (70) 21 (70) 30.00 0.999
(21 .600)
Effective
Leakage Area
ACII at (I.HI. Method)
C N 50 Pascals cm2 (square Inches)
353.30 0.536 12.03 1.359.6
(210.74)
335.86 0.568 8.63 1.351.0
(209.40)
Equivalent
Leakage Area
(Canadian Method)
c«2 (square Inches)
2.305.48
(357.35)
2.358.6
(365.59)
0)
-------
House Code: C39A
A-14
-------
REPORT ON MEASUREMENTS AND MITIGATION
HOUSE CODE: C39A
DESCRIPTION: This is a split level house with half-basement. The basement
is not finished. The house has a garage. The basement was built with sump
hole. Forced air heating ducts pass under the slab.
DIAGNOSTIC INVESTIGATION: Potential areas of infiltration were found in
open block, 2 large cracks along the front basement wall. Leaks around
ventiliation ducts and sewer lines were sampled and showed a concentration of
2900 pCi/1. Grab samples ranged from 140-800 pCi/1. The air duct register in
the family room read 7 pCi/1.
BEFORE RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
EARLY SPRING CONCENTRATION:(State of New Jersey): 1500 pCi.l
DATE LOCATION CONCENTRATION
(pCi/1)
6/70 to 6/11 basement
10.4
8/19 to 8/21 basement
7.5
9/21 to 9/23 basement
8.3
A-15
-------
b)
PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
6/6 to 6/13
max " 230
8/7 to 8/13
max " 1250
basement
mm
avg
o
40
basement
min
avg "
10
30
A-16
-------
AFTER RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
DATE
LOCATION
CONCENTRATION
(PCI/1)
11/17 to 11/20
basement- (heating on) 4.3
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
8/29. to 9/3
11/4 to 11/17
basement -
Level I radon max " 14
reduction min " 1
plan avg " 9
basement -
Level II radon max " 14
reduction min " 0
plan avg " 7
A-17
-------
'A" Floorplan
Kitchen
Lav
Family
Room
Down
Bedroom
Dining Room
New Heating Supply Ducts
cfl
Master
Bedroom
4..L-Duct thru closet*
Ltl
Down
Living Room
. C
C
Duct thru Closet*
Bedroom
•To fans in attic.
-. . Floor Grills Sealed
Slab on Grade
Basement
Chimney
•Up
Sub Slab Ventilation Duct ;'
I /
Footer Drains
A-18
-------
RADON REDUCTION PLAN
House Code: C39A
Phase I
Basement Area
1. Seal and evacuate sump hole (see attached diagram).
(a) exhaust pipe to exit building through roof with care taken to
minimize visual impact on living areas
2. Seal wall and floor cracks and penetrations
(specifically seal open block tops on each side of basement window,
at corner where slab level attaches to basement wall and other
locations where open blocks are found during site inspection.
3. Supply makeup combustion air to furnace area (passively)
Slab on Grade Area
1. Seal and depressurize sub-slab duct work
(a) drill openings "1.3 cm ("1/2") through transit duct where access
allows. EPA guidelines should be followed for this activity.
2. Run new heating ducts to the kitchen and living room area.
3. Seal perimeter crack at slab-block intersection being careful to do it in
such a way as to allow future active or passive ventilation of the perimeter
crack at a later date.
Phase II
1. Increase fan to "15.2 cm (6") diameter
2. Inspect for holes and cracks previously missed and seal.
A-19
-------
Mop Board
Expansion Joint
(With Homosote Fill) x
Concrete Slab
Sheetrock
Earth Fill
Scale
r = r
Pipe To Outside
Fan
4' PVC Pipe
Galvanized Cover
Slab
\T
Sump Hole
f2 Stone
1/2" Plywood
2x4 Stud Wall
2x4 Sill
Solid L - Block
8" Concrete Block
(Hollow Core)
Clay Weeping Tile
Block Wall
A-20
-------
IIOIISK TKSTS
Hauae C39A
(4/30/86)
Temperature Temperature Barometric
Volume In out pressure Correlation
m3 (fi3) 'C CKJ *C (*IM Pascals coefficient
Effective Equivalent
Leakuye Area Leakage Area
ACM at (I.HI. Method) (Canadian Method)
N 50 Pascals c«2 (square Inches) cm^ (square inches)
Iliiscmrnl door closed: '''
1.1 1
(21.
Hu.Si:
61 J
(21.
.6 21 (70) 15.6 (60) 30.00 0.996 324.14 0.506 6.52
600)
mi.'iit door o|ien: ''I
.6 21 (70) 15.6 (60) 30.00 0.907 283.35 0.589 7.89
600)
1 .263
(185
1.172
(181
.1
.29)
4
73)
1 .970
(305
2.085
(323
.8
.47)
.6
.27)
41* «• »»
llOUSl fKXSSUIE (r»»c«IO
^ to > •>
uuusc riussuu (P..t.i»)
-------
House Code: C46A
A-22
-------
REPORT ON MEASUREMENTS AND MITIGATION
HOUSE CODE: C46A
DESCRIPTION: This is a split-level with half slab and a, half, semi-finished
basement. The basement has been divided into 2 rooms with the larger of the
two with indoor/outdoor carpeting and wall panelling covering the cinder
block. An attached garage is approximately 6" below the slab of the house.
DIAGNOSTIC INVESTIGATION: No major cracks or openings were found in the
basement, although it was impossible to investigate walls and floor in the
finished portion of the basement. A floor drain was concealed in a closet.
Grab samples in the floor drain ranged from 13,000 to 19,000 pCi/1.
BEFORE RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
WINTER CONCENTRATION:(State of New Jersey):.635 pCi/1
DATE LOCATION CONCENTRATION
(PCi/1)
6/25 to 6/27 basement (house closed) 771.9
6/27 to 6/29 basement 433
7/31 to 8/9 basement 157
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE LOCATION CONCENTRATION
(PCi/1)
6/25 to 7/1 basement - closed max. " 1100
min. * 900
avg. " 950
8/7 to 8/13 basement max. * 600
min. " 30
* 220
A-2 3
-------
AFTER RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
DATE
LOCATION
CONCENTRATION
(pCi/1)
8/7 to 8/9
12/9 to 12/11
1/3/87 to 1/5/87
basement (After Level 1) 238.5
radon reduction
family room 5.3
basement
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(PCi/1)
8/7 to 8/13
11/21 to 11/23
basement
basement
max.
min.
avg.
max.
min.
avg.
30
3
13
17
4
9
A-24
-------
'A" Floorplan
Kitchen
Lav
Family
Room
Down
Bedroom
Dining Room
New Heating Supply Ducts
cfl
Master
Bedroom
Vr— Duct thru closet4
Down
Living Room
C "[. C
Duct thru Closet*
Bedroom
*To fans in attic.
Floor Grills Sealed
Slab on Grade
1
*
r
V
Basement
j BJ Chimney
^ Up
1
1
i
Sub Slab Ventilation Duct »
\ ffl !
Sump Hole
Footer Drains
A-25
-------
Mop Board
Expansion Joint
(With Homosote F1
Concrete Slab
Sheetrock
Earth Fin
Scale
r= r
Pipe To Outside
Fan
4- PVC Pipe
Galvanized Cover
Slab
1/2" Plywood
2x4 Stud Wall
2x4 Sill
Solid L - Block
8" Concrete Block
(Hollow Core)
J
Sump Hole
'2 Stone
Clay Weeping Tile
Block Wall
A-26
-------
RADON REDUCTION PLAN
House Code:
Phase I
Basement Area
C46A
1. Seal and evacuate sump hole (see attached diagram).
(a) exhaust pipe to exit building through roof with care taken to
minimize visual impact on living areas
2. Seal wall and floor cracks and penetrations
(specifically seal open block tops on each side of basement window,
at corner where slab level attaches to basement wall and other
location that open blocks are found in during site inspection.
Slab on Grade Area
1. Seal and depressurize sub-slab duct work
(a) drill openings "1.3 cm ("1/2") through transit duct where access
allows. EPA guidelines should be followed for this activity.
2. Run new heating ducts to the kitchen and living room area.
3. Seal perimeter crack at slab-block intersection being careful to do it in
such a way as to allow future active or passive ventilation of the perimeter
crack at a later date.
Phase II
1. Increase fan to 15.24 (6") diameter
2. Inspect for holes and cracks previously missed and seal.
A-27
-------
HOUSE TESTS
House C46A
<4/30/8fi|
Tca|>er<)i
-------
House Code: C10B
A-29
-------
REPORT ON MEASUREMENTS AND READON REDUCTION PLAN
HOUSE CODE: C10B
DESCRIPTION: This is a split foyer house with a finished lower level divided
into a family room, 2 bedrooms, a 2 piece bathroom and a utility room. The
family room has a woodstove and poured concrete patio behind the family room.
DIAGNOSTIC INVESTIGATION: Few entry routes were located due to the finish on
the slab level floor. A grab sample in the plumbing access in upstairs
bedroom tub showed a concentration of 0 pCi/1. The slab perimeter crack was
exposed in places showing one likely source of infiltration.
BEFORE RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
EARLY SPRING CONCENTRATION:(State of New Jersey):. 670 pCi/1
DATE
LOCATION
CONCENTRATION
(pCi/1)
8/15 to 8/17
8/17 to 8/19
8/17 to 8/19
8/17 to 8/19
family room
family room
family room
family room
15.8
9.8
4.2
2.5
A-30
-------
Fan
Undergrade
Pipes
Lav.
Family Room
Utility
Garage
A-31
-------
HOUSE TESTS
House C1OU
14/30/80)
Volume
*3 (fi:>)
apiH-iit in e Temperature Baroiietrlc
In out pressure Correlaliun
T. CKI *C ('I-') Pascals coefficient
Effective
Leakage Area
ACH at |I.HI. Method)
50 Pascals c»2 (square Inches)
Equivalent.
Leakage Area
(Canaillan Netluid)
:a2 (s<|iiare Incites)
JO-i .5
(14,
(70)
21.1 (70)
30.00
0. 905
255.77 0.667
14.63
I.179.80
(182.87)
2.255.16
(349.55)
OJ
CO
-------
House Code: C31B
A-33
-------
REPORT ON MEASUREMENTS AND RADON REDUCTION PLAN
HOUSE CODE: C31B
DESCRIPTION: This is a bi-level home. The downstairs portion is divided into
general use rooms. The utility room and furnace is located here. The garage
has been partially finished with a raised wooden floor. A storage room has
been added on behind the utility room. All living areas are finished.
DIAGNOSTIC INVESTIGATION: Grab samples were taken under wood floor above
garage slab: 3000 pCi/1; and in various walls, all less than 40 pCi/1. A grab
sample in an open block was 5 pCi/1.
BEFORE RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
EARLY SPRING CONCENTRATION:(State of New Jersey):. 691 pCi/1
DATE
LOCATION
CONCENTRATION
(PCi/1)
5/28 to 6/1
6/1 to 6/4
8/15 to 8/17
8/17 to 8/21
lower level 8.2
lower level 4.4
lower level - house closed 89.
lower level 76.6
A-34
-------
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
8/15 to 8/21
Lower Level
max. " 260
min. " 5
avg. " 65
AFTER RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
DATE
LOCATION
CONCENTRATION
(PCi/1)
11/9
11/9 to 11/15
11/17 to 11/20
Music Room
Music Room
Music Room (Heat on)
4.0
4.0
5.8
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
11/9 to 11/15
Music Room
5.8
A-3<
-------
Fan
Undergrade
Pipes
Lav.
Family Room
Utility
Garage
A-36
-------
RADON REDUCTION PLAN
House Code:
Phase I
C31B
1. In a trench about 2.54 cm. (I1) deep (below slab level), lay PVC pipe
around the outside of three block walls of the house. One connection on each
of the three walls to a fan will provide suction on the block walls. (See
attached diagram).
2. Seal perimeter crack on the lower level with polyurethane caulk.
3. Seal all plumbing penetrations.
Phase II
1. Supply makeup air to the furnace.
2. Passively supply dilution air to the cold air return ducts. When the
circulating system is on, it should draw in approximately 100 cfm of outside
air to dilute radon levels.
A-37
-------
HOUSK TKSTS
House C31B
14/30/86)
Teupcruture Tenperature Barometric
Viiliinu: In out pressure Correlation
Pascals coefficient
m3 (fi31 •(: CF) •(: (•(••)
ACII at
50 Pascals
Effective
Leakage Area
(I.HI, Method)
Equivalent
Leakage Area
(Canadian Method)
en2 (si|uare Inches) cm2 (square Inches)
464 .4
I 16.400)
21 (70)
21.1 (70)
30.00
0 907
305.01 0.585
11 .03
1 .254.8
(194.50)
2.223.8
(344.69)
OJ
CO
S
|
I -,,
4 *•
HOUSE PRESSURE
-------
House Code: C48B
A-39
-------
REPORT ON MEASUREMENTS AND RADON REDUCTION PLAN
HOUSE CODE: C48B
DESCRIPTION: This is a bi-level home. The lower level is slab-partially-
below-grade with only a small utility room and attached garage in an
unfinished state. An enclosure was added over a poured concrete patio behind
the front-to-back family room. A low crawl space under the ground level
entrance at the front of the house gives access to the front portion of the
foundation.
DIAGNOSTIC INVESTIGATION: Few slab or wall penetrations were found. A hole
was drilled in the floor of the front downstairs bedroom closet and a grab
sample showed a. concentration of 16,000 pCi/1. The foundation under the front
stoop was found to be incomplete causing earth to be exposed to the interior
structures of the house via the crawl space. A small amount of crushed stone
was found under the slab. The perimeter crack was a potential source of
infiltration.
PREMITIGATION MEASUREMENTS
a) CHARCOAL CANISTERS
EARLY SPRING CONCENTRATION:(State of New Jersey): 936 pCi/1
DATE LOCATION CONCENTRATION
(PCi/1)
5/30 to 6/1 downstairs- house closed 771.9
6/1 to 6/4 downstairs 37.6
6/4 to 6/5 downstairs 4
A-40
-------
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
11/4 to 11/9
downstairs
max " 30
ave." 8
A-41
-------
B1-Level
i/8"= r
Family Room
Bedroom
Lav
Storage
Garage
Diningroom
Kitchen
Lwingroom
Lav
Lav
naster
Bedroom
I
C C
Bedroom
Bedroom
A-42
-------
RADON REDUCTION PLAN
House Code:
C48B
a slab-partially-below-grade
Bi-level with finished lower level. This is
house with few penetrations through the slab.
Phase I
1. Because there is some crushed stone under the slab the first attempt will
be to use sub-slab ventilation. If at any point of installation this is not
effective then Phase II shall be implemented with the remainder of Phase I.
2. The perimeter crack shall be sealed using backer rod or equivalent and
pourable polyurethane in such a way that the crack can later be ventilated.
See Figure 1 for details.
3. All other slab penetrations shall be revealed and sealed.
plumbing stack, toilet soil pipe and water entry pipes.
These include
Phase II
1. In addition to Phase I, the perimeter crack shall be evacuated (Another
alternative here is to go directly to air-to-air heat exchanger ventilation)
2. Fault in the original construction affecting the foundation under the
steps will be repaired, replacing the present dirt and plywood portion with
block, then sealing any cracks.
A-43
-------
MOUSE TESTS
House C488
15/2/871
Temperature Temperature Barometric
Volnm: in out pressure Correlation
(fi'M 'C (•!••)
*C CF)
Pascals coefficient
Effective
Leakage Area
ACII at (LBL Method)
N 50 Pascals cm2 (square Inches)
Equivalent
Leakage Area
(Canadian Method)
m^ (square inrlics)
3
-------
House Code: C33C
A-45
-------
REPORT ON MEASUREMENTS AND RADON REDUCTION PLAN
HOUSE CODE: C33C
DESCRIPTION: This is a 2 story colonial house on slab with attached double
garage and add-on room behind the garage. Heating ducts run under the slab.
Soil was found to have substantially sub-sided under the slab.- A continuous
perimeter crack was located around the slab.
DIAGNOSTIC INVESTIGATION: Cracks in the floor tested with the smoke tube
showed air infiltration. Similarly, air entered from a hole drilled in the
floor. Air flow was from the interior to the exterior at the baseboard.
Grab samples taken of family room air show 0 pCi/1 of radon. Thermal by-
passes were found around the chimney, the attic scuttle and the plumbing
chase.
BEFORE RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
EARLY SPRING CONCENTRATION:(State of New Jersey): 1190 pCi/1
DATE LOCATION CONCENTRATION
(pCi/1)
6/22 to 6/24 livingroom
house closed 304.2
7/23 to 7/25 livingroom
house closed 106
7/25 to 7/27 livingroom
house closed 8.7
7.27 to 8/1 livingroom
house closed 8.5
A-46
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b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
AFTER RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
CONCENTRATION
(PCI/1)
6/16 to 6/24
7/23 to 8/1
livingroom max "
min ~
avg ~
livingroom max "
min "
avg
7500
0
2000
280
0
30
DATE
LOCATION
CONCENTRATION
(PCI/1)
10/4 to 10/10
10/4 to 10/10
11/17 to 11/20
11/17 to 11/20
small bedroom-
R. R. Plan Level I
furnace room-
R. R. Plan Level I
livingroom-
R. R. Plan Level II
livingroom-
R. R. Plan Level II
8.5
5.8
4.7
calculated
samples
4.7
R. R. = Radon Reduction
A-4 7
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b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
9/11 to 9/16
10/3 to 10/16
R. R. Plan Level I
R. R. Plan Level II
max
min
avg
max
min
avg
33
1
14
14
0
5
R.R. = Radon Reduction
A-48
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C" and "D" Floorplan
Dining Room
_
r
Up
Kitche
L
n
r *t
ramHy
Room
W D
Bedroom
9 Sub
9 ,. Cl-ih
• Suctioc -'
Ducts
~
oarage
Bedroom
c
Bedroom
B
Ba
ath
th
Down
Q
C
C
c
Master
Bedroom
Bedroom
o — -- Fan in Attic
™ I thru rioor i
A-49
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RADON REDUCTION PLAN
House Code: C33C
Phase I
Slab-on-Grade-Area
I. Seal heating grills from the sub-slab ductwork with plasticized concrete,
2. Vent sub-slab ductwork through storage area over garage to roof turbine.
Use 15.3 cm (6") duct and K-6 fan mounted in attic.
3. Seal floor cracks and penetrations
(specifically seal perimeter crack at wall slab joint, leaving a small
cavity beneath the seal that could later be ventilated, and plumbing
penetrations through slab)
4. Supply makeup combustion air to furnace area.
5. Run new heating ducts to the kitchen and livingroom areas.
Phase II
Slab on grade area
1. Ventilate perimeter crack with small fan.
2. Add heat recovery ventilation.
Phase 111
3. Increase fan on perimeter crack to 6" diameter size.
A-50
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IIOUSK TESTS
House C33C
(5/2/86)
Temperature Temperature Barometric
Volume hi o»l pressure Correlation
m3 Ifl3) *C Cl-'l *c <"F) Pascals coerflcient
.IB9.9 2) (70) 21.1 (70) 30.00 0.9U2
( 17.300)
Effective
Leakage Area
ACII at (I.U1. Method)
C N SO Pascals cm^ (square Inches)
142.74 0.776 10.34 776.06
(118.74)
Equivalent
Leakage Area
(Canadian Method)
cm (square inches)
1 .618.38
(250.85)
« » fc »»
HOUSE russuu (r..c.i.)
-------
House Code: C32D
A-52
-------
REPORT ON MEASUREMENTS AND RADON REDUCTION PLAN
HOUSE CODE: C32D
DESCRIPTION: This is a 2 story colonial with basement and garage. An
enclosed deck with crawlspace attaching to the basement through a former
exterior window was added on. A sump hole was located in the basement.
DIAGNOSTIC INVESTIGATION: The block wall was extremely porous with several
large cracks. Pressure under the slab was found to be different on opposite
sides of the basement implying some sub-slab blockage. Several major floor
cracks were found. Grab sampling in the air above the sump hole showed a 1200
pCi/1 level. Interior basement air that was grab sampled was found to range
from 3 - 360 pCi/1. Post-level I diagnostics revealed in leakage around
basement windows and at the block to wood juncture of the building.
BEFORE RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
EARLY SPRING CONCENTRATION:(State of New Jersey):. 1357 pCi/1
DATE LOCATION CONCENTRATION
(pCi/1)
6/19 to 6/21 basement 29.1
6/21 to 6/24 living room 7.2
A-53
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b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
6/16 to 6/25
8/29 to 9/3
7/23 to 8/11
living room max.
min.
avg.
living room max.
min.
avg
basement min.
max.
avg.
" 120
0
" 30
" 44
3
0
' 130
' 43
AFTER RADON REDUCITON MEASUREMENTS
a) CHARCOAL CANISTERS
DATE
LOCATION
CONCENTRATION
(PCi/1)
9/21 to 9/26
11/17 to 11/20
12/9 to 12/11
12/9 to 12/11
basement
level I R.R.
basement
fans sealed
family room
level II R.R. heat on
basement
20.1
8
5.1
11.3
R.R. = Radon Reduction
A-54
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b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
8/29 to 9/3
9/3 to 9/20
11/17 to 11/21
Level II - 1 fan
R.R.
II - 2 fans
R.R.
Level II -
R.R. exhaust raised
mm.
max.
avg.
min.
max.
avg.
min.
max.
avg.
3
55
20
5
180
73
3
10
5.7
R.R. = Radon Reduction
A-55
-------
«r« —J »r\"
C" and "D" Floorplan
W D
Dining Room
Kitchen
Bedroom
1 * * D
r
Up
L
Room
9 Sub
^— — z^j- - • Slab
• f _ . •,
1 Suctmr -
Ducts
GdT3Q6
Bedroom
Bedroom
Bath
Bath
Down
; c •
Master
Bedroom
Bedroom
Fan in Attic
thru Roof
Storage
A-56
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HOUSE TESTS
House C34D
(5/2/66)
Temperature Temperature
Volume In (nit
•3 (ft3) *C ('I-') 'C CF)
Barometric
pressure Correlation
Pascals coefficient
Effective
Leakage Area
ACH at (LBL Method)
50 Pascals cm2 (square Inches)
Equivalent
Leakage Area
(Canadian Method)
:m' (si|uarc Inches)
636. B
(22.488)
21 (70)
17.8 (64)
30.00
0.997
295.65 0.591
7.96
1.227.6
(190.28)
2.188.9
(339.28)
HOUSE russuu; (r..c.i.)
-------
House Code: C24E
A-58
-------
REPORT ON MEASUREMENTS AND MITIGATION
HOUSE CODE: C24E
DESCRIPTION: This is a split level with open earth crawlspace under the
living room and kitchen. The lower slab on grade level is 1/2 finished. The
interior of this house has been recently renovated. The finished slab on
grade portion has a fireplace and woodstove.
DIAGNOSTIC INVESTIGATION: The crawlspace area is open earth and extremely
damp. It is the principle location of soil gas entry to the house.
Foundation was blasted out of bedrock.
BEFORE RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
WINTER CONCENTRATION:(State of New Jersey): 426 pCi/1
DATE
LOCATION
CONCENTRATION
(PCi/1)
8/15 to '8/17
8/17 to 8/19
8/19 to 8/21
lower level
near crawlspace
(house closed)
lower level
lower level
90.9
2.5
1.3
A-59
-------
b) PYLON AB5 WITH PASSIVE RADON DETECTOR CONTINUOUS MONITOR:
DATE
LOCATION
CONCENTRATION
(pCi/1)
9/3 to 9/9
lower level
min. " 7
max " 210
avg. " 73
AFTER RADON REDUCTION MEASUREMENTS
a) CHARCOAL CANISTERS
DATE
LOCATION
CONCENTRATION
(pCl/1)
9/25 to 9/30
12/9 to 12/1
12/9 to 12/11
lower level
near crawlspace
lower level
near crawl space
heat on
living room
above crawlspace
heat on
3.0
7.2
12.3
A-60
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RADON REDUCTION PLAN
House Code: C24E
Level I
1. Work will concentrate on sealing and isolating the crawlspace.
2. Two layers of six mil plastic will be supported by a ankadrain fiber mat
and roofing paper. This entire assembly will be sealed to the block walls of
the crawlspace using first a caulking compound and then fir wood trim nailed
through the three layers to the block.
3. The block wall will be punctured at the back of the house and pipe will be
set in puncture and fitted with a fan. The fan will vent to the outside of
the house and be covered with a shield.
4. The interior opening to the crawlspace will be fitted with rubber sealing
so as to allow access but prevent in-leakage of air to room.
Level II
1. Increase fan to 15.24 cm (6") diameter.
2. Three wall suction from the exterior of the slab-on-grade level of the
house on three walls.
3. Sealing around the interior perimeter.
A-61
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HOUSE TESTS
House C24E
Tenpei aim c Temperature Baroaetrlc
Voliion- in out pressure Correlation
•3 (fr'l *C CM 'C Cfl Pascals coefficient
35B .8 21 (70) 21.1 (70) 30.00 O.U96
( 12,67;;)
Effective
Leakage Area
ACH at (I.BL Method!
C N 50 Pascals cm2 (square inches)
3A4.S3 0.596 17 . 7fi 1.522.45
(235.9B)
Equivalent
Leakage Area
(Canadian Method)
cm2 (square inches)
2.724 .96
(422.37)
M
4 t. •• ••
MOUSE rustuu (r»»u)
-------
APPENDIX B
HOMEOWNER PERMISSION FORM
B-l
-------
AGREEMENT NO.
BETWEEN
RESEARCH TRIANGLE INSTITUTE (RTI)
AND
OWNER(S) AND/OR TENANT(S) OF OCCUPIED HOME
NAME(S) - OWNERS
NAME(S) - TENANTS
I/We, as owners of the house and lands located at:
Clinton. NJ
or I/We, as tenants of the house and lands located at:
Clinton. NJ
agree to participate in a study sponsored by the U.S. Environmental Protection
Agency (EPA) and the New Jersey Department for Environmental Protection and
conducted by Research Triangle Institute (RTI), to develop experimental low-
cost radon mitigation methods for these premises; and I/we, hereby authorize
Research Triangle Institute's authorized representatives to install mitigation
devices or otherwise take any necessary steps to attempt to mitigate the radon
presence, if any. within the house and/or on the premises of the address given
above.
I/we understand that this authorization will allow Research Triangle
Institute's representatives to have access to this house and its surroundings
during reasonable working hours during a period beginning and
continuing through , at no cost to RTI, to the EPA. the U.S.
Government, and the State of New Jersey.
I/we realize that for effective mitigation RTI may be required to modify
the house design and/or structure for a reasonable period of time agreed upon
between the parties to this agreement, in writing, and that with its "Best
Efforts" RTI will attempt to return the house to an "as found" condition, at
no charge to the Homeowner(s) and/or Tenant(s). In consideration for my/our
being selected to participate in this study and other considerations. I/we
agree to indemnify and hold harmless RTI. the U.S. Government, and the State
of New Jersey for any injury to person or damage to property that may occur as
a result of the work done or omitted by or for RTI and/or the U.S. Government
and/or the State of New Jersey in connection with this study, including
without limitation, modifications to the house design and structure and the
installation of mitigation devices. I/we have been advised that the process
B-2
-------
of installing mitigation equipment may result in a temporary increase in radon
concentrations on the premises and that I/we may temporarily vacate the
premises during the mitigation process at no cost to RTI, the U.S. Government
or the State of New Jersey, or I/we may accept the inconvenience of the
process and remain on the premises, understanding that all steps reasonably
necessary will be taken to minimize these inconveniences.
RTI will treat the data and resident locations as confidential. All
reports to parties other than the EPA will be coded to prevent recognition of
the premises participating in the study.
I/we understand that any mitigation devices or installations will remain
attached to the premises and become the property of the owner, and RTI, the
U.S. Government, and the State of New Jersey shall have no responsibility for
the maintenance of such devices or the subsequent use or removal of such
devices: and we further understand that these procedures are experimental in
nature and that RTI, the U.S. Government, and the State of New Jersey make no
promises, nor accept any liability nor have responsibility for the success or
failure of the mitigation process, and I/we hereby agree to hold RTI and the
Government harmless for any of the possible detrimental effects of radon
exposure directly resulting from the performance of the process outlined
herein.
Subscribed to the day of , 1986.
Research Triangle Institute
Authorized Agent
Homeownerfs]
Tenant(s)
Witness
B-3
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1 REPORT NO.
EPA-600/8-87-027
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Development and Demonstration of Indoor Radon
Reduction Measures for 10 Homes in Clinton, New
jersey ___^_
5. REPORT DATE
July 1987
6. PERFORMING ORGANIZATION CODE
7.
Linda D. Michaels, Terry Brennan,
Andrew Viner, Arthur Mattes, ana William Turner
8. PERFORMING ORGA
471U-3065-52
g PERFORMING ORGANIZATION NAME AND ADDRESS
Research Triangle Institute
P.O. Box 12194
Research Triangle Park, North Carolina 27709
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-3992, Task 5
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Air and Energy Engineering Research Laboratory
Research Triangle Park, NC 27711
13. TYP6 OF REPORT AND PERIOD COVERED
Task Final; 4/86 - 1/87
14. SPONSORING AGENCY CODE
EPA/600/13
15. SUPPLEMENTARY NOTES AEERL project officer is Michael
919/541-4113.
C. Osborne, Mail Drop 54,
16. ABSTRACT
repOr^- discusses the development and demonstration of indoor radon
reduction methods for 10 houses in Clinton, New Jersey, where (in the spring of 1986)
the New Jersey Department of Environmental Protection (DEP) located a. cluster of
houses with extremely high radon levels. The work was to be completed before the
1986-87 winter heating season began. The demonstration houses were selected from
56 in the Clinton Knolls subdivision. All of these houses had shown radon concentra-
tions in excess of 64 pCi/1 when monitored in the spring of 1986. Each house was
inspected, and 10 representative houses were selected for the radon reduction demon-
stration project. Following intensive diagnostic work and monitoring in each house,
house- specific radon reduction plans were developed. With the agreement of the
homeowners, radon reduction systems were installed during the summer of 1986.
All 10 of the houses had radon concentrations reduced significantly by the fall of 1986.
The average cost of radon reduction was S3, 127.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Pollution
Radon
Atmosphere Con-
tamination Control
Residential Buildings
Monitors
Ventilation
Pollution Control
Stationary Sources
Indoor Air
Soil Gas
13B
07B
06K
13 M
14G
13 A
Release to Public
19. SECURITY CLASS (This Report)
Unclassified
20. SECURITY CLASS (This page)
Unclassified
1. NO. OF PAGES'
174
22. PRICE '
EPA Form 2220-1 O-73)
B-4
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