IAQ

In most conditioned spaces, the Mixing Jet Ventilation (MJV) systems are commonly installed. Relying on turbulent mixing, MJV homogeneously controls the room environment. However, Indoor Air Quality (IAQ), draft, and noise can sometimes be drawbacks of MJV systems. In late the 70s, Displacement Ventilation (DV) was first introduced. By supplying low supply velocity air from the floor or lower wall, a stratification zone is formed which forces pollutants to be collected near the ceiling and allows clean air to remain in the breathing zone.

Investigates IAQ by making subjective assessments of perceived air pollution caused by human bioeffluents. A panel comprising 107 people reported on odour intensities and acceptability of bioeffluents from 54 other people as occupants. Twenty per cent of the judges described dissatisfaction caused by bioeffluents at 1.5 on the Yaglou's odour intensity scale. To satisfy 80% of the judges entering the chamber, a ventilation rate of around 7 litres per second per person was necessary.

Discusses this rarely examined aspect of indoor air quality. Specifically describes a study carried out on an unoccupied apartment on a road with heavy traffic, on the third floor of a block dating from 1955. The aim was to evaluate the transfer of pollution between outside and inside. Parameters considered were ventilation status, season, outdoor pollution levels, and the presence of adsorbing materials.

The article presents IAQ requirements for healthy office buildings in Nordic climates, based on the results of an epidemiological study of a multistorey office building in Helsinki, Finland. Summarizes the results of the study and gives recommendations and their limitations.

An evaluation of the effect of air humidification on various factors was performed, including skin dryness and mucosa, allergic and asthmatic reactions and perception of IAQ. A six period cross over trial was conducted on 290 office workers. A total of 211 workers who returned at least two weekly diaries and who had experienced both humidified and nonhumidified conditions were included in the analyses. The main outcome was characterized by dryness, irritation or itching of skin and eyes, of the throat and nasal dryness.

The aim of the study was to evaluate the effect of humidification on the odour, acceptability and stuffiness of indoor air. The air of two wings of an office building in turn were ventilated with air of 30%-40% humidity in a six period cross over trial. The third wing was used as a non-humidified control. A panel assessed the quality of indoor air weekly. Mean intraindividual differences were used to assess the roles of sex, current smoking and age. The study found that humidified air was regarded as more odorous and stuffy than non-humidified air.

States that carbon dioxide measurements are commonly used to indicate fresh air in a building, also particulate levels. The study's aim was to evaluate the relationship between carbon dioxide and particulate levels and subjective human responses in office building without previous or present indoor air problems. Six separate ventilation zones were defined and carbon dioxide and particulate measurements taken with direct-reading instruments. A self-reporting questionnaire, designed in Sweden was used for the subjective human responses.

As is well known, SBS involves symptoms such as eye, skin and upper airway irritation, headache, and fatigue. A multifactorial study was made among workers in consecutive cases of sick buildings to investigate the links between these symptoms, exposure to environmental factors, and personal factors. The total indoor hydrocarbon concentration had a significant correlation to the symptoms but other indoor exposures such as room temperature, air humidity, and formaldehyde or carbon dioxide concentration did not.

Considers how ventilation provision affects the indoor air quality in tropical climates, and the energy aspect. Describes a series of research projects aimed at obtaining a detailed database of IAQ, ventilation and energy measurements, carried out in Singapore in the mid to late nineties. Obtained the overall energy consumption of a dedicated air handling unit that served the zones in which the relevant IAQ and ventilation measurements were done. Presents the results for five air conditioned buildings in Singapore.

Residential buildings in Korea are equipped with only radiant heating systems (Ondol). Fenestration openings alone provide the ventilation, and the system is dependent on occupant control. Describes studies of the ventilation in these buildings carried out to assess the health of the indoor climate. The present study suggests strategies for maintaining the healthy environment and obtains data for the applications of ventilation systems to high-rise apartment buildings. Compares IAQ levels and ventilation rates for natural and mechanical ventilation.