Indoor and Built Environment

Inhalation of radon and its progeny are the most important component of public exposure to natural radiations. Many epidemiological studies have established the fact that radon and radon progeny are associated with increased incidence of lung cancer. Beside health concerns, radon is an important consideration in other fields, e.g. hydrological research, detection of geological fault lines, prediction of earthquake, uranium deposits and oil exploration. The importance of the subject compelled many scientists to develop methods for measurement and mitigation of radon. During last decade many studies for measurement of radon and thoron have been conducted in Azad Kashmir. In most studies, the techniques used involve the usage of solid state nuclear track detectors. Building materials, including granite, marbles, gravel aggregates, bricks, sand and soil have been characterized through radon exhalation rate studies. Several research articles have been published, reporting indoor radon measurements in dwellings and at workplaces. Though these studies have provided preliminary information about radon levels in the area, however, data obtained are still unable to convey clear information to readers. This review paper attempts to organize the radon data to provide a clearer understanding and roadmap for radon measurements in Azad Kashmir.

Worldwide, especially in societies with higher education levels, traditional settlements are important components of cultural heritage in terms of sustainability. However, the recent wave of urbanisation that has been experienced in Turkey has placed significant pressure on traditional structures. The District of Kemaliye, which has largely preserved its traditional texture for various reasons, is a small town in the Erzincan Province of Turkey. The aim of this study is to determine the quality of life of the traditional settlement pattern of Kemaliye to contribute to its ecological, spatial and socio-cultural sustainability. A public opinion survey was carried out with the aim of identifying the public’s needs and demands and its socio-cultural characteristics. The survey also aimed to determine the quality of urban life in Kemaliye. Multidimensional statistical techniques were used to identify the most important environmental, socio-cultural, infrastructural and regional factors that affected the public’s views of quality of urban life in Kemaliye. Based on these findings, suggestions were formulated for the efficient use of resources in urban redevelopment efforts and to provide a basis for the new settlement plans that are projected to be carried out for the city centre of Kemaliye and its vicinity.

This study aims to investigate the natural lighting performance in indoor and semi-open spaces of urban vernacular architecture in the Mediterranean region. In vernacular architecture, natural lighting was the main source of light available and was largely achieved through the central courtyard. In this framework, an in-depth lighting performance analysis was carried out in a typical and representative traditional urban complex in the walled city of Nicosia, Cyprus. In-situ lighting measurements, as well as software simulations, were employed in order to assess the lighting performance of the building complex. The study has shown that lighting levels of semi-open and indoor spaces on the first floor are sufficient; whereas, the dense urban fabric, and the introverted character of vernacular architecture, create certain limitations to the lighting levels in indoor spaces of the ground floor. On the other hand, the positive impact of the inner courtyard to the lighting levels of semi-open and indoor spaces has been verified.

Among indoor environmental quality components, such as lighting, thermal, acoustic and spatial conditions, lighting quality is one of the significant factors that affect human environmental health and work productivity, especially as they pertain to human visual comfort and satisfaction. With the help of advanced sensing technologies, this study utilized a human body’s physiological principle to instantly react to its ambient environmental lighting condition to estimate a user’s visual sensation. Thus, this research investigated the possibility of using human eye pupil sizes as a measure of visual sensation in a workplace setting, especially in the high lighting colour temperature (5000 K) that is very common in modern office environments with the adoption of natural colour-fluorescent light bulbs. A series of experiments involving human subjects in an environmental chamber were conducted. Various ambient lighting conditions were generated to initiate and test pupil size changes and visual sensations. Statistical analyses of the collected data were conducted to help elucidate research findings. This research directed its focus toward pupil size change patterns as a means of assessing the human subject’s visual sensations, and to determine a potential use for this physiological principle in the control loop of a lighting system in a conventional workplace environment.

In the UK, a rule of thumb applied to air permeability is commonly employed when estimating background ventilation rates from pressurisation test data. However, this may lead to significant errors in estimating the infiltration rates in UK new-build dwellings, resulting in poor estimation of the dwellings in-use energy and CO₂ emissions, and the adoption of ventilation strategies leading to either unacceptable indoor air quality or unnecessary energy consumption. In this paper, a preliminary investigation into the applicability of the rule of thumb is undertaken. Background ventilation rates in four new-build dwellings in the UK are determined using the tracer gas decay method and also the pressurisation (blower door) method coupled with both the conventional n₅₀/20 and (in the UK) q₅₀/20 rule of thumb, and Sherman’s modified rule of thumb, which takes into account other building-related factors. The conventional method overestimated the air-change rate in two of the dwellings and underestimated it in the other two dwellings. The modified rule of thumb produced comparable results for two of the dwellings, but significantly underestimated the air-change rate in the other two dwellings. These results suggest that more work needs to be done to devise appropriate climate and building-related correction factors for the UK.

This study investigates the effectiveness of ventilation design strategies for general hospital wards in terms of virus removal capacity. A typical semi-enclosed six-bed general ward of Hong Kong hospitals and three respiratory viruses, namely Middle East respiratory syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus (SARS-CoV) and H1N1 influenza virus, were chosen for the computational fluid dynamics (CFD) simulation of airflow field and virus dispersion inside the ward. The results demonstrated that the location of an infected patient would affect the infection risks to other occupants and healthcare workers inside the same hospital ward, and an increased air change rate in the ward could reduce the risk of infection from direct contact and inhalation. It was found that an air change rate of 9 h⁻¹ could effectively minimize the deposition and floating time of respiratory virus particles while maximizing energy efficiency. This study should provide a useful source of reference for the hospital management to mitigate the risk of infection with MERS or other airborne transmitted viruses through better ventilation design strategies.

Steady indoor environments are perceived poor at high temperatures and require a high energy input to cool to comfortable operative temperatures. The introduction of airflow variations in such environments improves occupant perception and is shown to be far more energy efficient than cooling the entire space as only the occupants’ are cooled. However, with this method the risk of draft is high and use of velocity variations reduces the risk. This paper discusses and compares two occupant cooling methods in a classroom setup. Cooling by reducing the room temperature and enhanced convective cooling with intermittent air velocities. The experiments were performed in a full scale mockup classroom with a total of 85 student-participants. In study 1, participants sat in a classroom for about 60 min, in one of two temperature conditions: 20℃ and 25℃. In study 2, all participants sat in a room with a temperature of 25℃, but airflow variation in the sitting zone was manipulated. In both studies, the participants performed various tasks and answered questionnaires on their perception of the indoor climate. As shown here, higher classroom temperature deteriorates human perception of the indoor climate, and the use of intermittent air velocities improves the perception of indoor climate just like cooling by reducing the room air temperature. The results reveal that convective cooling can effectively be used as an energy efficient method of cooling in school environments.

Electricity generators of varying capacities are popularly utilized in Nigeria as alternative source of power owing to the unreliability of electricity supply through the national grid. This study evaluated the impact of emissions from generating sets on air quality and human health in selected areas of Abeokuta city, Nigeria. The levels of particulates (PM₁, PM₃), carbon monoxide, carbon dioxide, sulphur oxides, nitrogen oxides, nitrogen dioxide, hydrogen sulphide and methane were monitored using portable samplers. Copies of questionnaire were administered to generator operators and nearby residents so as to collect additional information. The capacities of sampled generators ranged from 1 to 25 kVA. The range of mean concentrations of PM₁ (4.7–219.2 µg/m³), PM₃ (7.8–251.6 µg/m³), carbon dioxide (4.5–10.9%), methane (0.0–1.2 ppm), carbon monoxide (141.1–4167.0 ppm), NO_x (4.0–85.7 ppm), methane (2.3–31.0 ppm), sulphur oxides (3.5–65.6 ppm) and hydrogen sulphide (0.0–0.7 ppm) was highest at generator sites. The distance of sample sites to generator locations accounted for 14–66% variation of pollutants levels. Ailments frequently suffered by the exposed residents included nasal congestion (66%), cough (33%), headache (24%) and fever (12%). A national policy on appropriate use of electricity generator is urgently needed in Nigeria.

Typical Meteorological Years (TMY) were prepared in Poland due to the introduction of obligatory energy certification for buildings. They are based on source data collected by the Institute of Meteorology and Water Management from 1971 to 2000. Predictions indicate that until the end of the 21st century, the air temperature will increase. Therefore, the characteristics obtained with the use of TMY may differ from the energy demand of buildings used nowadays. This article compares energy demand calculated with the use of TMY and subsequent climatic data from 2001 to 2012, for three different locations in Poland. The analyses were performed with the use of the dynamic simulation computer program, for typical living quarters in a multifamily residential building with different construction and window orientation. Results obtained with the use of TMY and subsequent climatic data show that the typical years can be used for the evaluation of heating demand. However, cooling demand calculated with the use of TMY was significantly lower in comparison with the mean cooling demand for the years 2001–2012. This may distort the energy needs and indoor environment conditions in summer, and cause discomfort or unnecessary energy use in presently occupied dwellings.

This work presents the results of the absorbed dose rates and estimated effective doses of the surface soils samples collected from different factories in the industrial region of Suez City, Egypt using high resolution gamma spectrometry system (HpGe) detector. The average activity concentrations of ²²⁶Ra, ²³⁸U, ²³²Th and ⁴⁰K in fertilizer factories were: 74.54 ± 3.7, 26.54 ± 1.3, 14.68 ± 0.73 and 233 ± 11.68 Bq kg⁻¹, respectively, in Ceramic factories were: 75.91 ± 3.7, 31.35 ± 1.56, 20.34 ± 1.01 and 255 ± 12.76 Bq kg⁻¹, respectively, in textile factories were: 121 ± 6.07, 36.22 ± 1.81, 25.80 ± 1.29 and 1076 ± 53.83 Bq kg⁻¹, respectively, in oil factories were: 76.24 ± 3.81, 25.90 ± 1.29, 15.26 ± 0.7 and 266 ± 13.31 Bq kg⁻¹, respectively, and in steel factory were: 79.72 ± 3.98, 35.22 ± 1.76, 11.95 ± 0.59 and 163 ± 8.16 Bq kg⁻¹, respectively. The calculated absorbed dose rates in factories were: 31.13 ± 1.55, 37.86 ± 1.89, 79.04 ± 3.95, 32.64 ± 1.63 and 29.99 ± 1.49 nGy h⁻¹, respectively. Also, the annual effective dose in the above factories were: 0.03 ± 0.001, 0.04 ± 0.002, 0.09 ± 0.004, 0.03 ± 0.001 and 0.036 ± 0.001 mSv y⁻¹, respectively. Also, the exposure of workers to radon was studied using solid state nuclear track detectors (CR-39). The results indicate that feeding materials variably affect the radioactivity measurements of the surface soil in different factories.

Field monitoring is critical in the examination of indoor air quality (IAQ) which offers an integrated assessment of human exposure. A good measurement protocol includes appropriate methodologies and compliance of quality control and quality assurance procedures. In China, there has been a huge economic growth in the past 20 years and living standard for Chinese citizens has been improving with a rapid development in urban cities and infrastructures. With these developments, there have been a growth of increasing pollution sources, and IAQ has been a major concern to the government and many Chinese citizens with widespread reports of the coherent health impacts. However, the indoor monitoring in China is full of technical challenges. In this paper, we review the difficulties in conducting IAQ assessment in China. Techniques and practical consideration have been proposed accordingly.