Environmental Engineering Reference
In-Depth Information
Fan
Exhaust
Grade Level
Caulk
Drainpipe
Cover
Sump
Soil Gas
Slab
Pump
Footing
Aggregate
Existing Drain Tile
Circling the House
Figure 11.22
Sump/subslab ventilation used to control radon in a house. (From
USEPA,
Radon Reduction Techniques
f
or Detached Houses,
EPA/625/5-86/019, 1988.)
blocks. An application of a soil-gas ventilation system applied to a sump is
illustrated in
Figure 11.22
.
A soil-gas ventilation system coupled with sealing
substructure cracks is the most effective mitigation method available to
reduce high radon levels in residences. Typical radon reduction efficiencies
are on the order of 90 to 95%.
In houses built on crawlspaces, radon reduction can be achieved by
mechanically ventilating the air space between the ground and the floor.
Typically, this is accomplished by using an exhaust fan. Such exhaust fans
may also be used to control moisture levels in crawlspaces as well. It is
desirable in such applications to use fans resistant to corrosion.
Readings
ASHRAE,
Ventilation for Acceptable Indoor Air Quality
, Standard 62-1989, American
Society of Heating, Refrigerating and Air-conditioning Engineers, Atlanta, 1989.
Bearge, D.W.,
Indoor Air Quality and HVAC Systems
, CRC Press/Lewis Publishers,
Boca Raton, F., 1993.
Fanger, P.O., The comfort equation for indoor air quality,
ASHRAE J
., October, 33,
1989.
Godish, T.,
Sick Buildings: Definition, Diagnosis and Mitigation
, CRC Press/Lewis Pub-
lishers, Boca Raton, FL, 347, 1996, chap. 10.
Godish, T., Ventilation, in
Indoor Air Pollution Control
, Lewis Publishers, Chelsea, MI,
175, 1989, chap. 5.
Godish, T. and Spengler, J., Relationships between ventilation and indoor air quality:
a review,
Indoor Air
, 6, 135, 1996.
