This paper describes a method for the determination of optimal indoor conditions, using three parameter indexes: PMV (predicted mean vote) for thermal comfort, CO2 concentration for indoor air quality and cooling/heating load for efficient use of energy. A performance index of the HVAC system is calculating by adding square errors between actual and desired values. It is then minimized to find optimal indoor air conditions.
This paper deals with the simulation of air flow pattern in an office in Singapore (22.5 m x 84 m) with a typical day environmental conditions. Thermal comfort and indoor air quality audit, as well as ventilation measurements are used for validation of the simulation results.
Provision of good IAQ in buildings located close to a busy road requires application of air filtration systems which are efficient for submicrometer and especially ultra fine particles, since traffic emissions are associated with particles in these size ranges. A study has been conducted in which a filtration system of an office building was designed according to measured outdoor air conditions and theoretically predicted indoor air conditions. The performance of the system was then validated by field measurements of particle concentration levels indoors and outdoors.
Interior Alaska has indoor air quality issues similar to other far northern communities associated with long cold winters and reduced ventilation rates. Moreover, geological features in the hills around Fairbanks, Alaska increase the likelihood of elevated radon levels. Over thirty percent of the tested homes in the hills around Fairbanks had radon levels > 4 pCi/L compared with a nationwide average of 7%. Active sub-slab depressurization systems tested were very effective in reducing indoor radon concentrations (average reduction of over 90% for 8 homes).
An intervention study was carried out in eleven elementary schools in Trondheim, Norway. Three schools with poor ventilation standard, four schools with carpets, and four reference schools participated. Carpets were replaced by vinyl flooring and the poor ventilation systems were upgraded. Altogether 1100 children aged twelve to thirteen years and 400 teachers were all included in the study. The baseline registration of health related symptoms was performed during January/February 1997. The questionnaires were repeated, after the interventions, in February 1998 and 1999.
The Indoor Air Quality Committee of the Boston Society of Architects was invited to evaluate a large brick school building erected in 1963 to serve 1600 students. The investigation included a written questionnaire, evaluation of air using the ASTM E981 (modified) bioassay, fungal and bacterial testing, real time monitoring of carbon dioxide, carbon monoxide, respirable particulate, total volatile organic compounds, relative humidity and temperature. The survey and testing enumerated many potential causes for poor IAQ.
A study of 120 randomly selected classrooms in 30 schools in central and south Texas, USA was conducted to begin assembling baseline information on the condition of indoor air in Texas elementary schools. Part I of the study consisted of questionnaires sent to all teachers and staff in the schools to obtain information about the use of their rooms, room contents and their perceptions of its indoor air quality. Part II consisted of walkthroughs in each school and the 120 classrooms to obtain information on the building design, HVAC system and condition of the space/building.
The Texas Elementary School Indoor Air Study (TESIAS) involved several phases, including single-day continuous monitoring of carbon dioxide (CO2) in 120 randomly selected classrooms in two school districts. The median time-averaged and peak CO CO2 concentrations were 1,286 ppm and 2,062 ppm, respectively. The time-averaged CO2 concentration exceeded 1,000 ppm in 66% of the classrooms. The peak CO2 concentration exceeded 1,000 ppm in 88% of the classrooms and 3,000 ppm in 21% of the classrooms.
A research program has been initiated to focus on obtaining quantitative data in existing elementary schools through a longitudinal study with controls, interventions, and cross-sectional components. The overall objective of this program is to quantify the effects of simultaneous control of indoor exposures (i.e., thermal, indoor air quality or IAQ, lighting, and acoustics) on specific measures of human response, student and teacher performance, and productivity. The pilot study is being conducted in six elementary schools in Montgomery County Maryland.
Construction in healthcare facilities is a major risk for airborne agents infecting immune compromised patients. Standard air quality analysis has included air sampling for airborne fungi. These culture data require weeks for transport, incubation and identification. During a demolition and construction of a new medical facility an infection control risk assessment(ICRA) determined pre-construction precautions and surveillance methods. The surveillance utilized real time air particle analysis and culture methods to determine relevant indicators of potential hazards.