field study

Maintaining the airtightness of building envelopes is a key factor for the energy efficiency of buildings. A fast and reliable detection of leaks plays a decisive role, especially during building renovations. For this reason, work has been done in recent years to apply an acoustic beamforming method that enables the fast, simple, and large-area detection of leaks in building envelopes. This method is based on a microphone array technology and assumes that sound primarily follows the same paths as air through the building envelope.

As newer homes are being built tighter than the existing housing stock, questions have been raised about the concentrations of pollutants of concern in new homes and how mechanical ventilation systems can address this issue. This study measured pollutants of concern in 70 new homes with mechanical ventilation in California, USA and compared the results to a previous study of home without mechanical ventilation. The key pollutants were measured using both time-integrated and time-resolved over a one-week period and included formaldehyde, PM2.5 and NO2.

The association between indoor air quality (IAQ) and sleep quality was investigated in this study. A total of 27 participants (14 males and 13 females, 20-33 yrs.) without any sleep disorders and chronic diseases were recruited and divided into two groups: a polysomnography (PSG) group and a non-PSG group. The IAQ was changed by opening or closing windows. There were two phases for the experiment and two nights in each phase including one adaptive night and one test night, and around one-week washout period between two phases.

Beijing is in the Cold Climate Zone of China. This study carries out a long-term survey of indoor environmental parameters, the clothing of occupants, and the metabolic rate of occupants as well as people’s voting of their sensation in classrooms in Beijing. The study was conducted in 2011 and 2012, trying to explore people’s requirement of indoor thermal environment. Relationships between thermal parameters and people’s sensations are found. The acceptable temperature range can meet the requirements of most of users.

Considering school students spend up to one third of their day inside classrooms, it’s surprising how few detailed empirical studies have been conducted into how the thermal environment of classrooms affects students’ comfort and performance. Whereas PMV tends to exaggerate warm discomfort for adults, the literature suggests it underestimate children’s actual thermal sensation, but there is no coherent explanation for this in terms of metabolic or other physiological differences to date.

In order to research the indoor thermal conditions and residential thermal comfort in low-pressure plateau climate, a field study was conducted from December 2007 to February 2008 of 20 residential buildings in Lhasa. A total of 44 participants provided 356 sets of physical measurements together with subjective questionnaires that were used to collect the data. By linear regression analysis of responses based on the ASHRAE seven-point thermal sensation scale, the neutral air temperature of the total samples based on thermal sensation was 19.3℃.

Natural ventilation has been appraised as the main strategy in environmental control of airborne infection in resource-limited healthcare facilities. While natural ventilation offers a low-cost alternative in diluting and removing contaminated air, its’ performance in actual settings is not fully understood. This paper reports a cross-sectional field study of six hospitals in Thailand with an emphasis on ventilation performance of naturally-ventilated hospital wards and AII rooms. The results showed that ventilation rates of 3-26 ACH could be achieved in hospital wards.

This paper presents the findings of a short-term monitoring exercise and questionnaire surveyto assess the thermal comfort conditions actually being achieved in 6 Iranian Office buildings.The findings of the questionnaire and monitoring are compared to give confidence that thequestionnaire is accurately reflecting the calculated comfort conditions obtained from thephysically monitoring and site observations.

Reinforcement of air-tightness and thermalinsulation in the indoors leads to the declinein air-change rate. Moreover, due toincreased chemical substances on furniture,the indoor air-quality becomes worse andmay induce various health problenls, namelythe condition known as the Sick BuildingSyndrome(SB S).Many tools and methods are being developedto improve indoor air-quality.

The air quality in a subway-train was studied to suggest optimal design criteria and operationconditions based on the ventilation demand by passengers. The C02 emitted from thepassengers was the tracer for this study. The C02 bioeffluent from a human body was firstlyquantified and used for the data analysis. Then the C02 concentration was monitored in asubway-train being operated.