This paper reports mainly on field studies were indoor overnight CO2 levels are monitored along with outdoor ventilation rates in bedrooms where room air conditioners are employed.The results of laboratory experiments using two typical RACs (room air conditioners) are also reported and discussed.
This paper describes a study of the relationships between indoor environmental factors and individual work performance in a call center. The productivity benefits of ventilation rates appeared small, for the worker performance, only high temperature had a statistically significant negative impact on productivity. But it appears that the degree of understaffing and shift length have an impact on productivity too.
To satisfy the optimal environment in agricultural buildings, much effort is made to controlventilation rate and indoor temperature. However, distribution of fresh air is equally important for animal performance and welfare. So far, no sensor is available to measure and to control airflow pattern continuously in a ventilated building. Therefore, an airflow pattern sensor was developed to measure the trajectory of a nonisothermal air jet in a building with a single or multiple air inlet(s).
In this study, the houses located in the northern region of Japan had been investigated. The investigation included the measurement of the ventilation rate using four different methods, namely the constant concentration method, measurement of airflow at inlet/outlet and two kinds of PFT method. This paper shows the relationship between the measurement results of ventilation rate via these four measurement methods. It is found that the amount of outdoor air introduced is insufficient for many houses and some of the used ventilation systems are not properly operated.
The air exchange rate is a determinant factor for the indor air quality in a given spaces. If it is lower than the required it may cause the so caled sick building syndrome. The ultimate result depends, obviously, also on the nature and strength of the sources emisions. In this work the natural
The paper reports on findings from a series of experiments where the supply flow rate wasvaried periodically in time. All experiments were conducted in a small scale model with water as operating fluid. The flow was visualised by adding particles to the water and the streaks were recorded with a digital camera. The main result is that there exist variations that generate a role up of the base flow by generation of vortices that are shed into the stagnant region.
A personalized ventilation system combined with a seat is introduced in this paper. This kind ofventilation seat is able to provide occupants with improved air quality, individual control and energysavings. A thermal manikin with an artificial lung was used to investigate several fundamental issues on this novel ventilation system. We tested the performances of the eight different air supply nozzles within the flow rate range from 0.1 l/s to 3.0 l/s. The highest pollutant reduction of inhaled air about 80% is achieved by one nozzle named SCN at the flow rate of 3.0 l/s.
That addendum 62n modifies the ANSI/ASHRAE Standard 62 "Ventilation for Acceptable Indoor Air Quality, it contains an update to the minimum prescribed ventilation rates and includes ventilation airflow "additivity" for dilution of people-source and building source contaminants.
The Minimum Ventilation Rate standard for dwellings is essential not only to provide occupant health and comfort, but also to remove and dilute the dominant pollutants. The purpose of this survey is to clarify and compare the regulations, standards or guidelines of ventilation requirements for residential buildings of various countries. The studies are based on the many literatures and interviews with the specialists in building regulation.
Major ventilation developments covering systems, measurements and design methods have taken place over the last 25 years. Our understanding about the impact of ventilation on the indoor environment and energy use has also evolved. This paper outlines these developments. Many future challenges are considered including minimum ventilation rates, energy efficient cooling, cost effective heat recovery and the development of calculation techniques.
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