United States
Environmental Protection
Aaencv
Air and Energy Engineering
Research Laboratory
Research Triangle Park NC 27711
Research and Development
EPA/600/S8-90/062 Sept. 1990
EPA Project Summary
Interim Radon-Resistant
Construction Guidelines for Use
in Florida-1989
Thomas D. Pugh
This project was initiated with the ob-
jective of investigating, analyzing, and
developing radon-resistant construction
guidelines which are consistent with
other building codes and which could be
applied to Florida.
A literature search was conducted in
which available information was obtained
on radon remediation techniques, new
construction methods, and existing
codes (e.g., those in Sweden and
Canada) for radon-resistant buildings.
Techniques identified by the research
were amended, modified, or supple-
mented for incorporation into draft
model guidelines for new construction
in format consistent with the Standard
Building Code promulgated by the
Southern Building Code Congress In-
ternational, Inc.
A technical review advisory commit-
tee which included building'contractors,
architects, engineers and representa-
tives of federal, state and local govern-
ments was formed during the develop-
ment of the guidelines. The committee
provided input and recommended
changes to the draft guidelines.
Although this project has resulted in
guidelines for recommended construc-
tion practices, it should be coupled with
a carefully planned and implemented
program of experimentation. Eventually
this approach will lead to building code
provisions which are scientifically de-
fensible, cost effective, reliable, and
easily incorporated into standard con-
struction practice.
This Project Summary was developed
by EPA's Air and Energy Engineering
Research Laboratory, Research Triangle
Park, NC, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title ( See project report ordering infor-
mation at back).
Introduction
Over the past decade there'has been
growing concern about health effects asso-
ciated with exposure to radon and its prog--'
eny. Florida is the first state in the nation to
establish standards which set limits on ra-
don progeny in buildings. Many currently
available publications address mitigation
techniques; However, few studies docu-
ment radon-resistant methods for new con-
struction, and mitigation techniques may
not be the most appropriate ones for* new
construction. In addition, many factors in
the southeastern U. S. make existing re-
search conducted in the northeast difficult
to apply here. These factors include geol-
ogy, climate, common building practices,
and lifestyles.
The approach to identifying ideal radon-
resistant features is two-fold: (1) it is neces-
sary to determine the likely entry routes for
radon into the building, and (2) standard
building practices and details that appear
responsible for allowing radon into a struc-
ture should be examined to determine how
they could be modified to create a radon
barrier. These possible modifications re-
quire much more investigation.
The problem of elevated radon concen-
trations in homes can be approached from
two directions: by filtering out or'diluting the
radon and its progeny once they are inside
the dwelling, or by preventing the radon-
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carrying soil gas from entering the home.
Radon filtration/dilution is a less than
perfect solution because: (1) it has a rather
high initial cost, (2) as an active system it will
require maintenance, (3) it is susceptible to
owner interference, (4) it requires energy to
operate, and (5) it has a negative impact on
other energy conservation measures.
Systems that prevent soil gas from enter-
ing abuiiding may be further subdivided into
two classes: those which are totally pas-
sive, and active systems, those which require
continuous energy inputs.
Active systems, perhaps the mosttested
and documented, can be further divided
into those drawing soil gas from beneath
the slab of a building and venting it to the
outdoors where it is quickly diluted to safe
concentrations, and those that attempt lo_
reduce the emergence of soil gas by con-
tinually pumping a small volume of air be-
neath the slab. Both systems have some
negative characteristics.
A thorough study of the literature, fol-
lowed by detailed experimentation of the
more promising methods for use in Florida,
should lead to the establishment of firm
protocols for radon-resistant new home
construction. The guidelines developed in
this report are based on the best information
obtained to date.
Procedures
Aliterature search wasconducted in which
information was obtained on radon reme-
diation techniques, new construction
methods, and codes (e.g., those in Sweden
and Canada) for radon-resistant buildings.
The Swedish codes had to be translated
into Englishbefore they could be analyzed.
The effectiveness of each technique was
evaluated, and those techniques with spe-
cific application to southern construction
were noted.
AlechnjcaJj«yJgwTiadvisory _CQmmjttee__
which included building contractors, archi-"
tects, engineers, and representatives of
federal, state, and local governments was
formed during the development phase of
the guidelines. The committee provided in-
put and recommended changes to the draft
guidelines.
Results/Discussion
The full report contains 11 sections: (1)
General, (2) Isolation membranes, (3) Con-
crete slabs in isolation systems, (4) Crawl
space construction, (5) Slab below grade
and basement construction, (6) Combined
construction types, (7) Soil gas ventilation
systems, (8) Other entry pathways for ra-
don, (9) Space conditioning systems, (10)
approved materials, caulks, and sealants,
and (11) Illustrated details.
Construction details and practices are
divided into: (1) those that are most confi-
dently recommended, (2) those which are
recommended, but with less confidence,
and (3) those which are recommended, but
with least confidence.
Conclusions
Institution of these interim guidelines
should be accompanied by the knowledge
that further experimentation and additions
to the literature may require revisions from
time to time.
T.D. Pugh Is with Florida A and M University, School of Architecture, Tallahassee, FL
32307
David C. Sanchez is the EPA Project Officer (see below).
The complete report, entitled "Interim Radon-Resistant Construction Guidelines for Use in
Florida --1989," (Order no. PB90-265 349AS; Cost: $15.00 cost subject to change) will be
available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Air and Energy Engineering Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States
Environmental Protection
Agency
Center for Environmental
Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use $300
EPA/600/S8-90-062
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