comfort

The interior zone and exterior zone air-handling units (AHU) can be connected through their return air ducts to become a new air-handling unit system, named OAHU system, which allows optimal choice of outside air intake and decouples sensible and latent cooling in a zone with lower sensible

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.

The article describes the advantages of heating designed as a system. It shows (among others) the features of balanced ventilation systems with heat recovery and compact ventilation appliances (heat recovery from ventilation exhaust air through a heat exchanger and a heat pump, to provide warm fresh air and domestic hot water).

Three experiments aiming at improving the atmosphere in industrial premices are described in this paper. The working conditions of the staff have been improved along with an amelioration of the process and quality of fabrication.The third example proves that a well adapted technical approach allows the improvement of working conditions coupled with an energy control.

Today the term of comfort includes the different aspects of indoor air quality, thermal, acoustical and visual comfort.Standardisation working groups have already worked in those different fields, and some standards already exist but it will certainly take several years to adapt them according to the countries and continents. Anyway environmental quality is a subjective perception and depends on many interactions. The aim is to insure comfort to the majority of people, but a personal adaptation of the user will always be necessary.

The notion of comfort is not easy to define. As it relies on elements partly subjective, a statistical approach of the user requirements is necessary.In order to reach the optimum reduction of the causes of discomfort, the profession in charge with the indoor air quality has adopted a certain number of rules that working groups of standardization try to improve and complete.

Variable Air Volume system use VAV boxes that serve open areas for five or more occupants, each zone is controlled with a single space temperature sensor. But VAV zone control strategies remained the same for the last years, so the designers have to consider that system : it provides a high quality environment for occupants, it permits the use of a smaller air-distribution system that is low cost and does not compromise building comfort or operating efficiency.

Through the analysis of the main international environmental performance rating systems (BREEAM, LEED and GBTool) this work aims to show international design tendencies concerning sustainable building equipment requirements and to provide to designers and researchers a broad view of sustainable building equipment solutions. Hence a particular attention was paid to the assessment approach provided by these systems for each requirement, focussing on the comparison of the building performance to a benchmark, on compliance with qualitative indications or use of best technologies.

In the Mediterranean countries, where the active solutions of air-conditioning must be avoided, natural ventilation allows improvement of indoor comfort which is generally critical in hot season, and reduction of building cooling loads.A three-dimensional zonal model for calculating temperature fields and airflow distributions insideunconditioned buildings was developed.

It is well understood that there are many sick professional buildings in use all over the world. Most of them are sited in or near the center of large cities where the ambient atmospheric conditions are not good. The sickness syndrome of those buildings combines both the indoor air quality and the local comfort regime. In many cases the responsibility for the formation of these syndromes lies with the not appropriate envelope design and the misuse of the building by the inhabitants.