Indoor and Built Environment

Adding mixed waste to coastal landfill areas is common in the Eastern Black Sea Region of Turkey. The area studied in this paper covers the coastal cities of Ordu, Giresun, Trabzon, and Rize. All these cities have gained extensive landfill areas from the shores just in front of them. Residential waste and rubble has been infilled along the shores of the cities for a distance of ~30—50 m from the sea side since the 1970s. This now supports a double lane road construction that follows the shore line. Both actions have caused damage to sea shore ecology.

The consequences of using mixed waste in landfill is discussed under the following headings: health impacts of wastes (scavenging sea gulls may carry infectious diseases); composition and chemical properties of wastes; visual and environmental impact; lack of integration with development plans for the re-use of filled lands; dumping techniques. This paper was prepared by analysis of maps, visual and photographic analysis, site investigations and evaluation of municipal records from the region.

This paper proposes a concept of dissatisfaction that is based on the correlation between the McIntyre and the ASHRAE votes of the ASHRAE RP-884 Adaptive Model Project — Data. The correlation shows that people who are voting with ASHRAE ·2 or beyond are not necessarily dissatisfied (which is the basic assumption of the classical PPD concept) and vice versa, that people who are voting between -1 and 1 are not necessarily satisfied with their thermal environment. The data set was divided into several factors (age, gender, building type, indoor conditions, outdoor temperatures) to analyze any dependencies of the preference on these factors. Processing the data finally lead to a predictive system that is — applied to the source data — a better predictor for preference than the PPD. This improvement needs affirmation by the application of the predictive system to an independent data set.

Indoor airborne bacteria and fungi levels can be selected as indicators of a healthy indoor environment. This study investigated the relationships between the airborne bacteria levels, fungi levels, and thermal environmental parameters, i.e., air temperature and relative humidity, in some offices with a Mechanical Ventilation and Air-Conditioning (MVAC) system operating. A total of 101 samples were collected from two typical Hong Kong air-conditioned office premises. There was evidence that the operation of the MVAC system would have significant influence on both of the indoor airborne bacteria and fungi levels. The results showed that no significant difference in airborne bacteria and fungi levels was observed between offices having similar thermal environments ( p > 0.05). However, significantly higher airborne bacteria and fungi levels were found in the same office during non-office hours when the air-conditioning system was shut down ( p<0.03). It was also reported that the airborne bacteria and fungi levels would be correlated with the thermal environmental parameters in some offices ( p<0.0001).

Concentrations of 26 volatile organic compounds (VOCs) were measured continuously for 7 days during winter in 96 homes in Quebec City, Canada. Characteristics of the houses and activities of the occupants were documented through detailed questionnaires filled out by one adult per household. VOCs were sampled using passive monitors and analyzed by gas chromatography-mass selective detector (GC-MSD). Results indicate contributions to indoor levels of some VOCs from combustion sources and recent renovation activities. Negative associations were seen between certain VOCs and the presence of carpets and furniture. In general, higher VOCs concentrations were found in newer houses. No association was found between individual VOCs and air change rate. Results suggest that multiple indoor sources contribute to occupants' exposure to VOCs during winter in Quebec City homes.

Aldehydes and BTEX concentrations were measured in 20 university libraries in Strasbourg (east of France) using Radiello passive sampling systems containing either DNPH or activated charcoal for aldehydes and BTEX, respectively. For the aldehydes, the conventional DNPH-derivatization method was used, followed by liquid chromatography coupled to UV detection while the BTEX were quantified by GC-PID. Aldehydes levels found inside the libraries ranged from 8.6 to 94.5 μg · m^×3 for formaldehyde, 3.7 to 25.9 μg · m^-3 for acetaldehyde, 2.1 to 58.8 μg · m^-3 for hexanal, 0.2 to 5.3 μg · m^-3 for benzaldehyde, and 0.7 to 16.3 μg · m^-3 for propionaldehyde. Their mean values are 28.6± 18.8 μg · m^-3 (formaldehyde), 10.2 ± 5.8 μg · m^-3 (acetaldehyde) and 15.1 ± 12.1 μg · m^-3 (hexanal), 1.1 ±1.1 for benzaldehyde and 2.8 ±3.3 for propionaldehyde, where the quoted errors correspond to 1σ level. Total BTEX concentrations were quantified in the same libraries and were usually relatively low (<20 μg · m ^-3) in all libraries, except for one where unusually high values (~295 μg · m^-3) were found. Excluding this latter, the means BTEX concentrations were (in units of μg · m^-3): 0.2 ±0.2 (benzene), 3.8 ±2.6 (toluene), 0.8 ±0.5 (ethyl benzene), 1.9 ± 1.2 (m- and p-xylenes), and 0.5 ±0.4 (o -xylene), where the quoted errors correspond again to 1σ.

The purpose of this study was to examine how temperature and relative humidity (RH) were affected by wood panels used as interior decorative materials in a container simulation under ventilation conditions. Hourly temperature and RH values were recorded in a residence and cross checked against data of average values from 1974 to 1990 for the Taipei area. Samples of 36 interior finishing materials were attached to one inside surface of a 35-cm3 simulation aluminum container with a controllable ventilation opening (10.5 x 8.5 cm). During the daily experimental period, programmable ventilation was performed from the 5th to 8th hour for exposure to a high humidity. The results revealed that a significantly lower average RH (when compared to a control chamber under the same climate conditions) occurred in the container lined with various wood species and some wood-based materials, while a significantly higher average RH was observed when the container was lined with inorganic materials after ventilation under humid conditions. The hygroscopic nature of the decorative materials could be classified into three types, in accordance with b values (humidity conditioning behavior index). The RH decreased curvilinearly with increasing panel thickness and A/V values (surface area of interior decorative materials attached to container/inside air volume of container), whereas b values increased with increasing panel thickness and A/V values.

The aim of this study was the assessment of bioaerosols in different indoor environments. The study was performed using volumetric culture plate air sampling to determine the concentration of viable bioaerosols. The results revealed that 60.9% of air samples from public places and all air samples collected in food processing plants had unacceptable levels of micro-organisms. This was based on a suggested standard which proposes that concentrations of viable micro-organisms should be no higher than 300 CFU · m^-3. More detailed study of the bioaerosols collected showed that the main parameters of interest for indoor air quality were fungi and further characterization allowed identification of the genera present in a particular place. Acceptable indoor air quality, by the above standard, was found at a university faculty, in a fast food restaurant, a cultural centre, a health centre and a hospital, while it was not acceptable in meat-, mustard-, olive- and infant food-processing plants because the concentrations of moulds were higher than 150 CFU· m ^-3 and the predominant genus identified was Penicillium.

This study analyzes the ventilation efficiency of a bedroom with a wall-mounted center-pivoting window. Numerical simulations and experiments were performed to investigate the airflow and the pollutant distribution in the bedroom. The air exchange rate and the carbon dioxide concentration profiles were investigated for various window opening angles and inlet wind velocities. The computational fluid dynamics analysis and experimental results presented provide a comprehensive understanding of the typical natural ventilation characteristics of a wall-mounted center-pivoting window in a bedroom of a typical home in Taiwan.

Air ionizers have seen increasing use as devices for improving indoor air quality, including applications designed to reduce the transmission of infection in healthcare environments. However, little attention has been given to understanding and quantifying the physical behavior of ions in indoor air. This study presents experimental data and a theoretical model to examine the factors that influence the concentration of ions in a ventilated room. The results demonstrate how, with an ionizer in operation, the ion concentration is governed by ion—ion interactions and electrical deposition at the walls, with the ventilation rate having a minimal influence. The results also demonstrate that an ion concentration > 10¹⁰ ions · m ^×3 is necessary for these electrical effects to be significant, which has implications for the suitability of an ionizer for a particular location.

The level of radionuclide concentration in water from bore-holes in selected areas of Ogbomosoland, a region consisting of five local governments, was determined. Concentration of ²³⁸U, ²³²Th, and ⁴⁰K was determined for the water samples from eight bore-holes around Ogbomosoland by γ-ray spectrometry with a high-purity germanium (HPGe) detector connected to a multichannel analyzer. All the water samples from these bore-holes were found to contain acceptable levels of radionuclides with mean activity values of 3.98 ±0.26, 11.00 ±2.58, and 17.73 ± 5.04 Bql ^-1 for ⁴⁰K, ²³²Th, and ²³⁸U, respectively showing that the mean activity of ²³⁸U for all the samples is the highest when compared with those of ⁴⁰K and ²³²Th. Water samples from Ikoyi had the highest radionuclide content although ⁴⁰K concentration was below detectable level. Water samples from Gambari were next to Ikoyi in radionuclide content, followed by Saja, Ajinopai, Kajola, Isale-Ora, Iresa-Apa, and Owode in that order. The mean absorbed dose rate for all the area is 0.123 mSvyr^-1 which is very low when compared to the recommended limit of 1mSvyr^-1 for bore-hole water. Overall, the radionuclide concentration of the bore-hole water supply in Ogbomosoland is, negligible and poses no radiological hazards to the public.