The initial findings of a project initiated in the University of Coimbra and dealing with the conjugated influence of multiple stressors in riding passengers are presented in this paper. A field study in public transportation buses was conducted, having been the subjective responses of the occupants collected and the physical parameters related to the thermal comfort, noise, vibration and air quality acquired. In the questionnaires, the PMV scale was used to evaluate the thermal aspects and, for the other stressors, a five-point scale, from very uncomfortable to very comfortable, was used.
The paper deals with the differences in the air quality between that perceived by the occupants (breathing zone) and that in the occupied zone as a whole. An environmental chamber with a displacement ventilation system has been used to carry out the measurements with the presence of a heated mannequin and heat sources. Measurement of the age of air distribution in the chamber were carried out for different room loads. It has been found that the perceived air quality for a seated mannequin is about 40% better than the average value in the occupied zone.
The paper presents a mathematical model, implemented in a general computer code, that can provide detailed information on velocity and temperature fields as well as pollutants concentrations prevailing in three-dimensional buildings of any geometrical complexity, for given external meteorological conditions. The model involves the partial differential equations governing flow and heat transfer in large enclosures containing heat sources. Turbulent flow is simulated and buoyancy effects are taken into account.
This paper reports the results of thermal comfort and indoor air quality measurements aboard aircraft from 43 flights on commercial airlines with a duration of more than 1 h. The measurements were performed continuously during the whole flight (from the departure gate to the arrival gate), and the parameters monitored were temperature, relative humidity and carbon dioxide concentration. The results were then compared with the ASHRAE Standards for the thermal comfort (ASHRAE Standard 55-92) and indoor air quality (ASHRAE Standard 62-89).
Many significant ASHRAE papers devoted to hospital ventilation have been published. In contrast, literature regarding ventilation in nursing facilities is rare. Nursing facilities are distinctly different from hospitals. This article provides some insight and guidance toward the design for such facilities.
A large number of the studies have indicated that chemical indoor air pollution has become an important environmental factor which influences the population's health. Nitrogenmonoxide and nitrogen dioxide are mainly produced by combustion at high temperatures and are formed by reactions between nitrogen and oxygen. Both nitrogen in the fuel and nitrogen in the air participate in reaction, NO is further oxidized and transferred into N02 in the atmosphere. Nitrogen dioxide is the most toxic of the nitrogen oxides and is the most important from view-point of health.
Source/sink models of volatile organic compound (VOC) emissions from building materials are reviewed and a multi-zone ventilation model is developed to predict concentrations of contaminants in rooms. The source model based on the principles of mass transfer and fluid flow presented by Zhang et al. (1995, 1996) is integrated into the multi-zone ventilation model. The characteristics of the parameters related to voc concentration, i.e. Schmidt number, ventilation rate and air velocity at the free stream are investigated by the sensitivity analysis.
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