Two families of macroscopic adsorption models are formulated, based on fundamental principles of adsorption science and technology, that may be used for macroscopic (e.g., whole‐building) contaminant dispersal analysis. The first family of adsorption models – the Equilibrium Adsorption (EA) Models – are based upon the simple requirement of adsorption equilibrium between adsorbent and room air. The second family – the Boundary Layer Diffusion Controlled Adsorption (BLDC) Models – add to the equilibrium requirement a boundary layer model for diffusion of the adsorbate from the room air to the adsorbent surface. Two members of each of these families are explicitly discussed, one based on the linear adsorption isotherm model and the other on the Langmuir isotherm model. The linear variants of each family are applied to model the adsorption dynamics of formaldehyde in gypsum wall board and compared to measured data. These applications and a more general consideration of the dynamic character of adsorption provided by these models indicate that simple physical adsorption and desorption transport processes h e the potential to significantly affect the dispersal of contaminants in buildings.

No abstract

No abstract

Natural ventilation has the potential to reduce first costs and operating costs for some commercial buildings while maintaining ventilation rates consistent with acceptable indoor air quality. While a recent surge of interest in Europe has advanced natural ventilation technology, much work is needed before this potential can be realized in the U.S. This report reviews the application of natural ventilation in commercial buildings, the technology, its potential advantages and related issues that need to be addressed. One area identified as a key to the realization of the potential advantages of natural ventilation is the emergence of hybrid natural and mechanical system strategies. The report also addresses opportunities and issues specific to the application of natural ventilation to commercial buildings in California including analysis of climate suitability via a new ventilative cooling metric, consideration of ambient air quality, and discussion of relevant codes and standards. Finally, current design and analysis processes and tools are reviewed, and a plan for the development of new design and analysis guidance and tools is described.

No abstract