A contaminated supply air system may have an adverse effect on indoor air quality. The aim of that study was to evaluate the effectiveness of different protective actions in achieving a clean supply air duct system on the one hand and to find out the location in the ductwork where most of the duct is accumulated. Measurements were made and presented in tables.
It appears that dust accumulation can be partly avoided by ducts protection during the whole of the construction transportation and storage phases and that no ducts with residual oil on the inner surface should be used.

A methodology for assessing the potential for a CO2 retrofit on an existing building is presented in this paper. A case study is described, the subject building is an Energy Star rated building that has a Direct Digital Control (DDC) system. The complexity of a CO2 ventilation control retrofit is related to the type of building control system currently in place. Significant energy savings are possible through the application of a well-conceived executed ventilation control strategy.

The model estimations aimed at identifying the most important parameters that determine air change rate along with predicting the indoor radon concentration to be expected in new Dutch dwellings under different ventilation conditions.Measurements were compared to the model estimations. To increase infiltration and thus to decrease radon concentation, opening the air inlets and inside doors proved to be efficient.

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.