scholarly journals Intra-Cage Air Change Rate on Forced-Air-Ventilated Micro-Isolation System-Environment within Cages: Carbon Dioxide and Oxygen Concentration.

1997 ◽  
Vol 46 (4) ◽  
pp. 251-257 ◽  
Author(s):  
Masakazu HASEGAWA ◽  
Yuzuru KURABAYASHI ◽  
Toshinori ISHII ◽  
Kazuya YOSHIDA ◽  
Nobukazu UEBAYASHI ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Concentration ◽  
Isolation System ◽  
Change Rate ◽  
System Environment ◽  
Air Change Rate ◽  
Forced Air

Stable carbon isotope labelled carbon dioxide as tracer gas for air change rate measurement in a ventilated single zone

2017 ◽  
Vol 115 ◽  
pp. 173-181 ◽  
Author(s):  
K.E. Anders Ohlsson ◽  
Bin Yang ◽  
Alf Ekblad ◽  
Christoffer Boman ◽  
Robin Nyström ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Isotope ◽  
Stable Carbon Isotope ◽  
Rate Measurement ◽  
Stable Carbon ◽  
Tracer Gas ◽  
Change Rate ◽  
Air Change Rate

scholarly journals Quantification of Air Rate Change by Selected Methods in a Typical Apartment Building

Buildings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 174
Author(s):  
Iveta Bullová ◽  
Peter Kapalo ◽  
Dušan Katunský
Keyword(s):  
Carbon Dioxide ◽  
Outdoor Environment ◽  
Experimental Measurements ◽  
Indoor Climate ◽  
Apartment Building ◽  
Change Rate ◽  
Air Exchange Rate ◽  
Wind Speeds ◽  
Air Change Rate ◽  
The Difference

An important parameter that affects indoor climate of buildings and also ventilation heat losses and gains is the speed of air change between the outdoor environment and the interior of buildings. Indoor air quality is therefore significantly associated with ventilation. Quantification of air change rate is complicated, because it is impacted by many parameters, the most variable of which is air flow. This study focuses on the determination and comparison of air change rate values in two methods by quantification of the aerodynamic coefficient Cp = Cpe − Cpi, so-called “aerodynamic quantification of the building” and the methodology based on “experimental measurements of carbon dioxide”. The study describes and takes into account the effect of wind, building parameters and air permeability for the building using “aerodynamic quantification of the building”. The paper compares these calculated results with the values obtained from experimental measurements method of carbon dioxide in a selected reference room in apartment building and evaluates the accuracy of the prediction of the air exchange rate obtained by these methods. At higher wind speeds the values of air change rate with considering the effect of openings are closer to the values obtained based on experimental measurements of carbon dioxide and the difference between the values without considering the effect of openings increases significantly.

scholarly journals Comparison of Downdraught and Up Draft Passive Air Conduction Systems (PACS) in a Winery Building

Buildings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 259
Author(s):  
Ádám László Katona ◽  
István Ervin Háber ◽  
István Kistelegdi
Keyword(s):  
Air Conditioning ◽  
Natural Ventilation ◽  
Dynamics Simulation ◽  
Computational Fluid Dynamics Simulation ◽  
General Applicability ◽  
Change Rate ◽  
Air Change Rate ◽  
Simulation Based ◽  
Ventilation Performance ◽  
Air Conduction

A huge portion of energy consumption in buildings comes from heating, ventilation, and air conditioning. Numerous previous works assessed the potential of natural ventilation compared to mechanical ventilation and proved their justification on the field. Nevertheless, it is a major difficulty to collect enough information from the literature to make decisions between different natural ventilation solutions with a given situation and boundary conditions. The current study tests the passive air conduction system (PACS) variations in the design phase of a medium-sized new winery’s cellar and production hall in Villány, Hungary. A computational fluid dynamics simulation based comparative analysis enabled to determine the differences in updraft (UD) and downdraught (DD) PACS, whereby the latter was found to be more efficient. While the DD PACS performed an air change range of 1.02 h−1 to 5.98 h−1, the UD PACS delivered −0.25 h−1 to 12.82 h−1 air change rate. The ventilation performance of the DD version possessed lower amplitudes, but the distribution was more balanced under different wind incident angles, thus this version was chosen for construction. It could be concluded that the DD PACS provides a more general applicability for natural ventilation in moderate climates and in small to medium scale industry hall domains with one in- and one outlet.

A New Oxygen Mask: Comparison with Other Clinical Methods of Giving Oxygen

1974 ◽  
Vol 2 (3) ◽  
pp. 214-219 ◽  
Author(s):  
W A Crosbie ◽  
J P Warren ◽  
L A Smith
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Concentration ◽  
Cor Pulmonale ◽  
Blood Levels ◽  
Supplementary Oxygen ◽  
Arterial Blood ◽  
Oxygen Mask ◽  
Clinical Methods ◽  
Expired Air

The performance of a new mask (Mix-O-Mask) for giving supplementary oxygen in clinical situations was compared with three other methods in a patient with cor pulmonale. Measurements were made of the intra-tracheal gas concentrations and arterial blood levels of oxygen and carbon dioxide. The new mask was as reliable as Ventimasks in delivering a claimed oxygen concentration and did not cause rebreathing of expired air. The mask proved durable when worn for sixteen hours in a day and was preferred for comfort by the patient.

Laser Ignition of Surgical Drape Materials in Air, 50% Oxygen, and 95% Oxygen

2004 ◽  
Vol 100 (5) ◽  
pp. 1167-1171 ◽  
Author(s):  
Gerald L. Wolf ◽  
George W. Sidebotham ◽  
Jackson L. P. Lazard ◽  
Jean G. Charchaflieh
Keyword(s):  
Carbon Dioxide ◽  
Operating Room ◽  
Oxygen Concentration ◽  
High Energy ◽  
Ignition Source ◽  
Laser Ignition ◽  
Surgical Tools ◽  
Time To Ignition ◽  
Room Fires ◽  
Surgical Laser

Background Operating room fires fueled by surgical drapes and ignited by high-energy surgical tools in air and oxygen-enriched atmospheres continue to occur. Methods The authors examined the time to ignition of huck towels and three commonly used surgical drape materials in air, 50% oxygen, and 95% oxygen using a carbon dioxide surgical laser as an ignition source. In addition, a phenol-polymer fabric was tested. Results In air, polypropylene and phenol polymer do not ignite. For polypropylene, the laser instantly vaporized a hole, and therefore, interaction between the laser and material ceased. When tested in combination with another material, the polypropylene time to ignition assumed the behavior of the material with which it was combined. For phenol polymer, the laser did not penetrate the material. Huck towels, cotton-polyester, and non-woven cellulose-polyester ignited in air with decreasing times to ignition. All tested materials ignited in 50% and 95% oxygen. Conclusion The results of this study reveal that with increasing oxygen concentration, the time to ignition becomes shorter, and the consequences become more severe. The possibility exists for manufacturers to develop drape materials that are safer than existing materials.

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