Most traditional elementary school classrooms here do not have air-conditioners and it often feel stuffy in classrooms located in the top floors. In addition, traditional classrooms widely have noise problem, so do the open educational classrooms. If the windows and doors are closed to reduce noise, it will result in the phenomenon of stuffiness, which largely prevents the external air entering...

The purpose of ventilation is to dilute or remove indoor contaminants that an occupant could be exposed to. It can be provided by mechanical or natural means. ASHRAE Standards including standards 62, 119, and 136 have all considered the contribution of infiltration in various ways, using methods and data from 20 years ago. The vast majority of homes in the United States and indeed the world are...

Based on natural ventilation design scheme for main transformer room of an indoor substation, different air distribution schemes were obtained by changing height and size of air inlets and outlets. Three-dimensional simulation of air distribution was conducted for the transformer room by using Computational Fluid Dynamics (CFD) method. Ventilation & cooling effect of different indoor ventilatio...

The present author has kept observation for concentrations of atmospheric radon, radon progeny and thoron progeny for several years at the campus of Fukushima Medical University. Accidentally, in the midst of an observation term, i.e., February 2005, the facility management group of the university changed a strategy for the manner of ventilation, probably because of a recession: (I) tidy everyd...

The residential and commercial buildings demand increase with rapidly growing population. It leads to the vertical growth of the buildings and needs proper ventilation and day-lighting. The natural air ventilation system is not significantly works in conventional structure, so fans and air conditioners are mandatory to meet the proper ventilation and space conditioning. Globally building sector...

Background: Radon, thoron and their progenies are the most important contributions to human exposure from natural sources. Radon exists in soil gas, building materials, Indoor atmosphere etc. Among all the natural sources of radiation dose to human beings, inhalation of radon contributes a lot. The work presented here emphasizes the long term measurements of radon, thoron and their proge...

This paper describes the fluid mechanics of natural ventilation by the combined effects of buoyancy and wind. Attention is restricted to transient draining flows in a space containing buoyant fluid, when the wind and buoyancy forces reinforce one another. The flows have been studied theoretically and the results compared with small-scale laboratory experiments. Connections between the enclosure...