A good indoor air quality is necessary to minimize exposure to airborne pollutants. The main source of those pollutants is often outdoor air. Ventilation and air filtration are the main solutions to reduce them.The aim of that study was to investigate the effects of air ventilation and filtration on submicrometer particle concentrations indoors thanks to a simple one zone mathematical model that simulates the time evolution of particle concentrations indoors.

In air-based systems, ducts deliver heat and cool air to conditioned spaces. Taking extra time to properly seal ducts during the installation along with repairing and patching leaks in HVAC duct systems will save cooling, heating and fan energy. With aerosol-sealing technology higher performance ducts in new and existing buildings potentially exist.

Air quality in conditioned spaces can be improved even in humid locations, in Florida. A field experiment in a Florida school confirmed that the use of a dual-path air-distribution system with low temperature air can maintain lower and more comfortable humidity levels.
Furthermore, that system coupled with a thermal energy storage (TES) keeps energy use as low as possible, and makes costs savings.

In this article the author gives some guidelines and techniques to conduct IAQ investigations at low cost for school staff with small budgets : first he advises occupant interviews, followed by a physical survey of the premices. An IAQ toolkit at low cost can be prepared for a first level type of investigation.
Then a monitor data analysis can be made with the measurements of temperature, relative humidity and CO2.
Finally an hypothesis can be developed even with little background and small budget.
But particular problems may require an experienced consultant.

An effective and successful O&M (operation and maintenance) program for schools begins at the very start of the project and not at its facility completion : key design issues must be covered during planning and design phases. The owner must be identified and listened to, the understanding of how the O&M staff works, what its capabilities and technology skill level are, will help in designing the right facility within the capability of available resources.

This paper is a report on humidity control in schools mainly located in hot and humid climates : according to the US Department of Energy's investigation, most of them, use packaged cooling equipments that are not able to manage space humidity effectively when delivering a high percentage of outdoor air. Those schools don't respect the requirements of the ANSI/ASHRAE standard 62-1999.
By using the dedicated outdoor system (DOAS) approach, ventilation effectiveness and humidity control can be improved and meet the recommendations of the ASHRAE 62-1999 standard.

A heat and mass transfer model of a walking clothed human has been developed in that study. That model predicts the transient thermal responses of the human and clothing giving temperatures, and latent heat losses. A mathematical model was developed for the simulation of the dynamic thermal behavior of clothing and its interaction with the system of human thermoregulation under walking conditions.

Up to now, the use of a single HVAC unit to handle ventilation along with mechanical cooling was the aim of designers : it permitted to curb the cost of a building's mechanical system. In this article the author suggests a new design approach to treat the ventilation air and to manage the latent cooling load for the building. It consists in "splitting" the building's total cooling load with a DOAS. This approach allows each component of the HVAC system to do what it does best.

In France, air quality in working areas is a matter of preoccupation for both the industry and the welfare state, that is in charge with the application of the rules and regulations in that field. The Labour Legislation and the Institution of Prevention, bring advice and assistance to the companies and final users.20 practical guides dealing with ventilation are listed at the end of the article.

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.