Modeling the IAQ Impact of HH1 Interventions in Inner-City Housing.
Modeling the IAQ Impact of HH1 Interventions in
Inner-City Housing.
(2605 K)
Emmerich, S. J.; Howard-Reed, C.; Gupte, A.
NISTIR 7212; 99 p. March 2005.
Sponsor:
Department of Housing and Urban Development, Washington,
DC
Keywords:
housing; impact; exposure; ventilation; residential
buildings; contaminants; simulations; occupants; zone
models; carbon dioxide; water vapor; nitrogen dioxide;
carbon monoxide; particles; radon; kitchens; bathrooms;
living rooms; stairways; dining rooms
Abstract:
The U.S. Department of Housing and Urban Development
(HUD) has identified a need to improve urban housing
conditions to protect children's health through its
Healthy Homes Initiative (HHI). One critical area within
this program is indoor air quality (IAQ), for example,
inadequate ventilation, moisture, combustion
by-products, etc. and the identification of effective
intervention strategies to address these issues. To
evaluate the impact of different interventions on indoor
contaminant concentrations and occupant exposures, a
simulation study was conducted using the multizone
airflow and contaminant dispersal model CONTAM. This
study modeled the exposures of a family of five to
concentrations of carbon dioxide, carbon monoxide,
nitrogen dioxide, water vapor, 0.3 /lm to 10 /lm
particles, radon, and volatile organic compounds in a
three-story townhouse. To investigate the impacts of
environmental conditions, the townhouse was modeled with
weather conditions from all four seasons in Boston, MA,
Miami, FL, and Seattle, WA. The model included outdoor
and indoor sources of the contaminants as well as
adsorption and deposition loss mechanisms. CONTAM
predicted ventilation rates, contaminant concentrations
and occupant exposures for a baseline case and eight
different interventions in each city/season combination.
The interventions included venting an otherwise unvented
space heater, replacement of a faulty stove, upgrading a
furnace filter, installation of air conditioning,
operation of kitchen and bathroom exhaust fans, ceasing
the practice of using a gas oven to heat the house,
tightening the house's envelope, and installation of
mechanical ventilation. Intervention strategies were
compared on an individual basis and a small sub-set of
interventions were considered to demonstrate an
intervention ranking system for identifying the best
strategy. The key parameter utilized in evaluating the
interventions is the concentration relative to the
baseline rather than comparison of absolute
concentrations to guideline values. Overall, a
combination of mechanical ventilation, local exhaust,
and an improved air filter was most effective for
reducing the largest number of contaminants in the
study.
