English

This paper provides a method for verifying the accuracy of computer models that simulate the performance of the airhandling components of three types of heating, ventilating, and air-conditioning systems: the constant volume terminal reheat system, the constant volume dual duct system, and the variable air volume system. To accomplish this, a detailed description of each system and its operating parameters was developed and a set of eight test conditions was generated, consisting of carefully chosen space loads and weather conditions. Each of

The authors of this paper have summarized and interpreted portions of the data collected for the Building Assessment Survey and Evaluation BASE study. They have measured then analyzed the concentrations of cat and dust-mite allergens in dust samples. Method and results are presented in this paper.

This paper is a presentation of statistics made by the US environmental protection agency BASE. A standardized protocol was used to measure bioaerosols whose air samples were collected in 100 large US office buildings in 1994-1998. A normative data on indoor environmental quality was thus obtained. Bacterial concentrations were compared by incubation temperature, location, season, and climate zone.

This study is an attempt to characterize the size relationships of bacteria and particles that mainly are of human origin. Their behaviour in relation to each other is observed and the results help in understanding how bacteria co-exist with particles of corresponding aerodynamic size across different six size ranges .

The supply CO2 based demand controlled ventilation (S-CO2-DCV) proposed in this paper is one of the strategies that could reduce energy use by reducing the unecessary overventilation of buildings. It is a compromise between the Multiple Space Equation (MSE) and the CO2-DCV technique : both the actual occupancy of the building with the critical zone ventilation requirement are taken into account.

The comparaison within the same Scandinavian airline company of the prevalence of health symptoms and perception of cabin air quality (CAQ) among commercial cabin crew with office workers was the main aim of this study. Improvement of the cabin air quality in commercial airlines is required.

When ASHRAE Standard 52.2-1999 was written, Standard Project Committee 52.2 recognized that the first dust loading step, also called the conditioning step, was not fully adequate for revealing the drop in efficiency that electret filters undergo during actual use. This is pointed out in the standards

Current models and test methods for determining filter efficiency ignore filter bypass, the air that circumvents filter media because of gaps around the filter or filter housing. In this paper, we develop a general model to estimate the size-resolved particle removal efficiency, including bypass, of HVAC filters. The model applies the measured pressure drop of the filter to determine the airflow through the bypass cracks and accounts for particle loss in the bypass cracks. We consider a particle

This paper presents a comprehensive discussion about past, present and future research focused on air curtain performance optimization. The past reserach mostly relies on simplified analytical solutions for jets. The present approach takes a more comprehensive step toward understanding and quantification of all major parameters that affect the air curtain flow field by utilization of modern analytical/computational and experimental techniques. The goal of future work is a systematic approach to map optimum air curtain performance as a function of the major design parameters.

A research project is being conducted at the National Research Council of Canada (NRC) to evaluate the effectiveness of current emergency ventilation strategies to control smoke spread in the event of a fire in two road tunnels. The research study includes numerical and experimental phases. The numerical phase uses computational fluid dynamics (CFD) models to study smoke ventilation in the tunnels. The experimental phase is used to calibrate and to partially validate
the chosen CFD models and to provide the necessary initial and boundary conditions.