air quality

In this work is analyzed the improvement of comfort conditions using confluent jets ventilation located near the floor level in front to the occupants in an experimental chamber. In this study are evaluated the thermal comfort, the local thermal discomfort and the air quality levels. The thermal comfort level is evaluated using the multi-nodal human thermal comfort numerical model, while the local thermal discomfort and the air quality levels are evaluated by the computational fluid dynamics numerical model.

With the continuous improvement of the energy performance of buildings, ventilation plays a crucial role in the control of pollutants from indoor sources and related comfort and health effects. However, the ventilation system itself could possibly also be a source of indoor air pollutants such as microbial contaminants. Profound scientific and technical knowledge on the impact of the design, installation and maintenance on the real performances of ventilation systems is currently lacking.

In this work the evaluation of indoor air quality in a classroom equipped with cross-flow ventilation is presented. A numerical methodology, based on comparison with experimental data, used in the evaluation of the air exchange rate, airflow rate and the age of the air, was applied in the first phase of this work. The evolution of carbon dioxide inside spaces, with different airflow typologies, was then predicted in the second part. The study was based on a school located in the South of Portugal. In the experimental methodology the tracer gas decay method was applied.

The air quality in laboratories has a profound affect on occupant health and safety. Reducing the timeof exposure and the amount of contaminant can improve the occupant environment and have directimpact on health and safety. In this study, a novel ventilation system which introduces benchexhausts is proposed. The system offers the potential for application in new and existing researchlaboratories to effectively remove airborne contaminants at the bench using a technology that is costeffective and efficient.

In this article the concept of a new energy-efficient office building and results of a 3-year monitoringare described. The monitoring was performed within the German funding programme ENOB.In this building most of the offices are naturally ventilated and passively cooled. Another focus of theenergy concept is on regenerative heating.Monitoring results show that the integrated planning enabled a very low consumption of energy forheating, ventilation, cooling and lighting.

The effect on Indoor Air Quality of painting at home while resident stays at home has been discussed. This paper presents a case study of the effects. A normal Scandinavian apartement has been refurnished with new paint on the walls and ceilings and the VOC emissions have been followed during eight weeks. Two types of low-emitting paint was selected for the study. A paint shop rolled two layers of new paint on the walls and ceiling in two rooms in the flat.

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.