In a test cell equipped with an operating table, a medical lamp and a manikin representing the surgeon, air velocity and tracer-gas concentration were automatically measured at more than 700 points. Numerical simulations were performed too for analyzing air quality in operating rooms. The results showed that the distribution of the contaminants depends strongly on the presence of obstacles like medical equipment and staff.
Until recently, the air quality did not play a major role in the planning of buildings. Air qualitywas simply understood to be synonymous with pollution-free and safe air. This approach,however, omitted consideration of how to achieve the well-being of the occupants. Asresearch has shown, elimination of pollutants is far from being sufficient and does notsignificantly reduce the dissatisfaction rate of building occupants. More recently, research hasaddressed the occupants perception of indoor air with the goal of increasing their satisfactionrate.
Optimum air distribution system should provide the basic requirements of healthy environment in the Operating Theatre, which depends in turn mainly on the air supply, extract outlet positions, and the operating table orientation. The complexity of the Surgical Operating Theatre requirements is shown in the present computational cases and the associated sophistication of the air treatment, to attain the guideline recommended by the National Health Service Estates of UK, was adequately represented.
Five air terminal devices (ATD) have been tested in a typical office workplace with a breathing thermal manikin. Tracer gas used to identify the amount of air inhaled and the amount of exhaled air re-inhaled. An index was used to assess the performance of ATD.
Concerning pollution in Hong Kong, the situation is particularly serious in public transfer locations such as public taxi transfer interchanges. Those locations are normally built at ground level under large building complexes, and poorly ventilated. The exhaust gas from vehicles are trapped and the air within those locations is smoky, filthy, and harmful for the passengers. This paper deals with a study on pollutant dispersion and distribution inside that type of sites at off-peak and peak hours. Measurement and analysis of field data are presented.
The aim of that study was to measure the performance of local ventilation for various parameter settings (nozzles and slots REEXS) and to demonstrate the benefit for real working situations.A test cabin was built, to measure the capture efficiency under reproducible cross draughts. Optimised REEXS hoods were used for the experiment : they proved to have a larger capture range compared to the conventional flanged hood. The results were so encouraging that an exhaust installation for 6 welding working places was completed.
The results of three independent studies involving 90 subjects, and using similar procedures and blind exposures have shown that increasing air quality (by decreasing the pollution load or by increasing the ventilation rate, with otherwise constant indoor climate conditions) can improve the performance of simulated office work (text typing, addition and proof-reading). An analysis of the combined data from these studies is presented to establish the relationship between air quality and performance in offices.
The effect on ventilation effectiveness parameters of the recirculation of air is investigated. The results of work with respect to air change effectiveness parameters is explained and extended to the effect of recirculation on the contaminant removal effectiveness parameter of local air quality index. It is demonstrated, first with respect to a simple system with one supply and exhaust and then by extension to a system with multiple exhausts, that it is possible to calculate the effect of recirculation by means of a simple algebraic expression.
The United States Environmental Protection Agency (EPA) has collected extensive indoor air quality data in 100 randomly selected office buildings following a standardized protocol developed for the Building Assessment Survey and Evaluation (BASE) study. These data were collected to provide normative data in typical office buildings for various uses including: a) basis for making policy and guidance development; b) hypothesis development and testing; c) input into risk assessments and environmental models; and, d) comparison of complaint buildings to "typical" building stock.
The aim of the study was to follow changes in allergens and airborne particles in the indoor environment during the first year in a newly started school. The building is from the sixties and was refurbished during the summer to be made suitable as a school. New internal walls and some new flooring were installed, and walls and ceilings were redecorated. Most of the furniture, textiles and lamps are new. Samples for allergen determination were collected by sampling settled dust with a vacuum cleaner. Airborne allergens were collected by a newly developed method involving an ionisator.
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