Determining the Outdoor Air Ventilation with Carbon Dioxide (CO2) as a Tracer Gas

Author(s):  
Ali Ijaz ◽  
Mohieddine Amor Benammar ◽  
Farid Touati ◽  
Abdullah Kadri
Author(s):  
A. Tristan Trupka ◽  
Mohammad H. Hosni ◽  
Byron W. Jones

An experimental study is performed in a mockup Boeing 767 cabin section consisting of eleven rows with seven seats per row. Carbon Dioxide (CO2) tracer gas is injected at a constant flow rate at a location of interest until concentrations in the cabin reach steady state. Ventilation equipment and flow rates representative of an actual aircraft are used for all experiments. Seats in the mockup are occupied by thermal manikins to simulate passenger heat load. A motorized beverage cart traverses the length of the cabin aisle passing by the injection location. The concentrations of tracer gas displaced by the cart are measured at locations throughout the cabin. Comparing these measurements to baseline readings taken with no cart movement, a map of the degree to which contaminant transport is affected by the beverage cart is calculated. The cabin mockup is supplied by 100% outdoor air through actual Boeing supply ductwork and linear diffusers along the cabin length above the aisles. The CO2 level is measured in the inlet air, measurement locations in the cabin, and exhaust air using nondispersive infrared (NDIR) sensors. Measured results are reported for all (54) seat locations downstream of the cart traverse/injection location for an injection location near the rear of the cabin. Analogous measurements are also conducted examining the effect of variation in cart speed and modified injection location.


2020 ◽  
Vol 12 (20) ◽  
pp. 8391
Author(s):  
Jinuk Lee ◽  
Sanghoon Park ◽  
Taeyeon Kim

A household unit of an existing apartment in which residents lived was selected, and the indoor air quality in each space of the unit was measured for analysis. Analysis of the measurement data indicated that the concentration of carbon dioxide (CO2) constantly increased beyond 1000 ppm when a resident stayed indoors for an hour or more. Specifically, the concentration of CO2 increased when the resident was asleep to a level wherein negative impacts on health were observed. Moreover, the inflow of particulate matter (PM) was mainly caused by natural ventilation from the outside rather than the behavior of indoor residents, which generated an insignificant amount of PM. This study proposes a new ventilation system for solving the above-described problems. According to the system, when a window is closed, the window cavity created between a new frame and the existing frame is utilized as an air path for ventilation. The application of this system ensures a stable amount of ventilation through forced ventilation and prevents the inflow of external PM. Moreover, this system was designed to recover indoor heat through the window cavity and facilitate the pre-heating of outdoor air through heat collection based on solar radiation during the day.


2018 ◽  
Vol 1 (2) ◽  
pp. 1-8
Author(s):  
Dody Hidayat

Kebakaran dapat terjadi dimana saja salah satunya dapat terjadi di alat transportasi air yakni kapal. Kebakaran selalu menyebabkan hal-hal yang tidak diinginkan baik kerugian material maupun ancaman keselamatan jiwa manusia. Seiring dari kejadian tersebut musibah kecelakaan kapal yang disebabkan oleh bahaya kebakaran sangatlah mungkin terjadi. Salah satu yang dapat mencegah kejadian kebakaran pada kapal haruslah dapat mendeteksi dini kebakaran tersebut. Untuk mendeteksi dini terjadinya kebakaran dikapal maka dirancanglah sebuah alat proteksi kebakaran otomatisberbasis adruino. Dimana Arduino merupakan board yang memiliki sebuah mikrokontroller sebagai  otak kendali sistem. Sistem otomatisasi atau controller tidak akan terlepas dengan apa yang disebut  dengan ‘sensor’. Sensor adalah sebuah alat untuk mendeteksi atau mengukut sesuatu yang digunakan untuk mengubah variasi mekanis, magnetis, panas, sinar dan kimia menjadi tegangan dan arus listrik. sistem yang dirancang ini dilengkapi dengan beberapa sensor diantaranya adalah sensor apiUV-Tron R2868, sensor asap MQ-2 dan kemudian sensor suhuDS18B20. Mikrokontroller sebagai pengendali akan merespon input yang berupa sensor tersebut ketika data yang dibaca oleh sensor mendeteksikebakaran diantaranya mendeteksi adanya asap, kemudian api dan suhu. Sebagai output dari sistem berupa racun api (fire extinguisher)dimana kandungan yang ada pada racun api tersebut berupa Dry Chemical Powder dan Carbon Dioxide (CO2) yang fungsinya digunakan untuk memadamkan api serta dilengkapi buzzer sebagai alarm peringatan jika terjadi kebakaran. 


2012 ◽  
Author(s):  
William R. Howard ◽  
Brian Wong ◽  
Michelle Okolica ◽  
Kimberly S. Bynum ◽  
R. A. James

2020 ◽  
Vol 25 (44) ◽  
pp. 4656-4661 ◽  
Author(s):  
Nikolaos Patelis ◽  
Mikes Doulaptsis ◽  
Stylianos Kykalos ◽  
Eleftherios Spartalis ◽  
Anastasios Maskanakis ◽  
...  

Background: Carbon dioxide (CO2) exists in nature around us. In the middle of the 20th century, the intraluminal injection of CO2 demonstrated similar results to those of Digital Subtraction Angiography (DSA) with an iodinated contrast agent (ICA). Since then, the technology behind CO2 DSA has developed significantly. Objective: The aim of this study is to inform physicians about the unique properties of CO2 and its physiology after intraluminal injection. Methods: An extensive search for English literature on the properties of CO2 and the physiology of intraluminal administration was conducted using Pubmed. Results: There is sufficient literature on the properties of CO2 and the physiology of CO2 DSA. A review of this literature explains what happens to the human organism after the injection of CO2. Conclusions: There is enough evidence that CO2 DSA is both effective, diagnostic and safe, but the properties of CO2 should be taken under consideration as complications occur, although rarely.


Cosmetics ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 56
Author(s):  
Tassahil Messas ◽  
Achraf Messas ◽  
George Kroumpouzos

Genitourinary syndrome of menopause (GSM) causes significant symptomatic aggravation that affects the quality of life (QoL). Vulvovaginal atrophy (VVA), the hallmark of GSM, is managed with topical non-hormonal therapy, including moisturizers and lubricants, and topical estrogen application. Patients not responding/being unsatisfied with previous local estrogen therapies are candidates for a noninvasive modality. Carbon dioxide (CO2) laser therapy, especially the fractionated type (FrCO2), has drawn considerable attention over the past two decades as a non-invasive treatment for GSM. This systematic review describes the accumulated evidence from 40 FrCO2 laser studies (3466 participants) in GSM/VVA. MEDLINE, Scopus and Cochrane databases were searched through April 2021. We analyze the effects of FrCO2 laser therapy on symptoms, sexual function, and QoL of patients with GSM/VVA. As shown in this review, FrCO2 laser therapy for GSM shows good efficacy and safety. This modality has the potential to advance female sexual wellness. Patient satisfaction was high in the studies included in this systematic review. However, there is a lack of level I evidence, and more randomized sham-controlled trials are required. Furthermore, several clinical questions, such as the number of sessions required that determine cost-effectiveness, should be addressed. Also, whether FrCO2 laser therapy may exert a synergistic effect with systemic and/or local hormonal/non-hormonal treatments, energy-based devices, and other modalities to treat GMS requires further investigation. Lastly, studies are required to compare FrCO2 laser therapy with other energy-based devices such as erbium:YAG laser and radiofrequency.


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