scholarly journals Analysis of Changes in the Concentration of Carbon Dioxide in Indoor Air of a Sports University

2021 ◽  
pp. 22-27
Author(s):  
NKh Davletova ◽  
EA Tafeeva
Keyword(s):  
Carbon Dioxide ◽  
Air Quality ◽  
Warm Season ◽  
Co2 Concentration ◽  
Cold Season ◽  
Permissible Limit ◽  
Standard Samples ◽  
Co2 Concentrations ◽  
School Day ◽  
The University

Introduction: Air quality of the premises of a sports university determines comfort and effectiveness of the educational and training processes and can be considered as a risk factor for students’ health. The purpose of our study was to give a hygienic assessment of changes in the indoor CO2 concentration at a sports university during the school day. Materials and methods: Air quality measurements were taken in twelve classrooms, six lecture halls, three sports halls, and a gym. The subjective assessment of air quality in classrooms was analyzed using data of a questionnaire-based survey of 651 students. Results: We found that differences in the proportion of air samples with elevated CO2 concentrations between the rooms were insignificant and ranged from 32 ± 4.66 % to 41.33 ± 2.84 % in the cold season (CS) and from 42.33 ± 2.85 % to 49.33 ± 4.08 % in the warm season (WS). Average CO2 concentrations in non-standard samples were 1,132.11 ± 93.21 ppm and 1,124.98 ± 98.51 ppm in the cold and warm season, respectively. We established that in the cold season, indoor CO2 concentration exceeded the permissible limit in 100 % of the classrooms, 50 % of the lecture halls and the gym already by 3.40 p.m. (15:40); by the end of the school day, the excess was registered in 100 % of the university rooms. In the warm season, CO2 concentrations were above the limit in the gym and in 33.3% of the lecture halls by 1 p.m. (13:00), and by 3.40 p.m. the excess was observed in 100 % of the rooms examined. Subjective air quality assessments indicated that most students often complained about stuffiness in classrooms; 25.25 ± 1.2 % of the respondents mentioned a strong odor in sports halls and the gym. Conclusion: In a significant part of sports university rooms, CO2 concentrations did not exceed permissible values for more than 80 % of school hours. Yet, after the fourth double lesson, this air quality indicator went beyond the standard value, and by the end of the school day indoor concentrations of carbon dioxide were above the permissible limit in 100 % of the university rooms.

scholarly journals Effects of Climatic Conditions, Season and Environmental Factors on CO2 Concentrations in Naturally Ventilated Primary Schools in Chile

2021 ◽  
Vol 13 (8) ◽  
pp. 4139
Author(s):  
Muriel Diaz ◽  
Mario Cools ◽  
Maureen Trebilcock ◽  
Beatriz Piderit-Moreno ◽  
Shady Attia
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Primary Schools ◽  
Co2 Concentration ◽  
Building Design ◽  
Climatic Conditions ◽  
Indoor Environmental Quality ◽  
Co2 Concentrations ◽  
The Impact

Between the ages of 6 and 18, children spend between 30 and 42 h a week at school, mostly indoors, where indoor environmental quality is usually deficient and does not favor learning. The difficulty of delivering indoor air quality (IAQ) in learning facilities is related to high occupancy rates and low interaction levels with windows. In non-industrialized countries, as in the cases presented, most classrooms have no mechanical ventilation, due to energy poverty and lack of normative requirements. This fact heavily impacts the indoor air quality and students’ learning outcomes. The aim of the paper is to identify the factors that determine acceptable CO2 concentrations. Therefore, it studies air quality in free-running and naturally ventilated primary schools in Chile, aiming to identify the impact of contextual, occupant, and building design factors, using CO2 concentration as a proxy for IAQ. The monitoring of CO2, temperature, and humidity revealed that indoor air CO2 concentration is above 1400 ppm most of the time, with peaks of 5000 ppm during the day, especially in winter. The statistical analysis indicates that CO2 is dependent on climate, seasonality, and indoor temperature, while it is independent of outside temperature in heated classrooms. The odds of having acceptable concentrations of CO2 are bigger when indoor temperatures are high, and there is a need to ventilate for cooling.

scholarly journals Effect of elevated carbon dioxide on biology and morphometric parameters of yellow stem borer, Scirpophaga incertulas infesting rice (Oryza sativa)

2022 ◽  
Vol 24 (1) ◽  
Author(s):  
GOURI SHANKAR GIRI ◽  
S. V. S. RAJU ◽  
S. D. MOHAPATRA ◽  
MUNMUN MOHAPATRA
Keyword(s):  
Carbon Dioxide ◽  
Larval Instar ◽  
Co2 Concentration ◽  
Elevated Carbon Dioxide ◽  
Stem Borer ◽  
Developmental Period ◽  
Morphometric Parameters ◽  
Scirpophaga Incertulas ◽  
Yellow Stem Borer ◽  
Co2 Concentrations

An experiment was conducted at Research Farm, National Rice Research Institute, Cuttack, Odisha, India to quantify the effect of elevated carbon dioxide (CO2) concentrations on the biology and morphometric parameters of yellow stem borer (Scirpophaga incertulas, Pyralidae, Lepidoptera). Yellow stem borer is one of the major pest of rice in the whole rice growing regions of South East Asia. The effect of three carbon dioxide concentrations i.e. 410 ppm (ambient), 550 ppm and 700 ppm on the duration of the developmental period as well as morphometric parameters of each stage of the lifecycle of the pest was analysed. It was found that, there was an increase in the duration of the developmental period of each stage of life cycle as the concentration of CO2 increases. However, the life span of the adult moth was significantly lower under the elevated CO2 concentrations when compared with ambient CO2 concentration. Morphometric parameters viz., mean length, width and weight of each larval instar, pupa and adult were found to be significantly higher in elevated concentrations of CO2 as compared to ambient concentration.

scholarly journals Mitigation Strategies for Overheating and High Carbon Dioxide Concentration within Institutional Buildings: A Case Study in Toronto, Canada

Buildings ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 124 ◽  
Author(s):  
Claire Tam ◽  
Yuqing Zhao ◽  
Zaiyi Liao ◽  
Lian Zhao
Keyword(s):  
Carbon Dioxide ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Air Temperature ◽  
Indoor Air ◽  
Indoor Environment ◽  
Thermal Conditions ◽  
Co2 Concentration ◽  
Hvac System

Indoor air quality and thermal conditions are important considerations when designing indoor spaces to ensure occupant health, satisfaction, and productivity. Carbon dioxide (CO2) concentration and indoor air temperature are two measurable parameters to assess air quality and thermal conditions within a space. Occupants are progressively affected by the indoor environment as the time spent indoors prolongs. Specifically, there is an interest in carrying out investigations on the indoor environment through surveying existing Heating, Ventilation, Air Conditioning (HVAC) system operations in classrooms. Indoor air temperature and CO2 concentration in multiple lecture halls in Toronto, Canada were monitored; observations consistently show high indoor air temperature (overheating) and high CO2 concentration. One classroom is chosen as a representative case study for this paper. The results verify a strong correlation between the number of occupants and the increase in air temperature and CO2 concentration. Building Energy Simulation (BES) is used to investigate the causes of discomfort in the classroom, and to identify methods for regulating the temperature and CO2 concentration. This paper proposes retro-commissioning strategies that could be implemented in institutional buildings; specifically, the increase of outdoor airflow rate and the addition of occupancy-based pre-active HVAC system control. The proposed retrofit cases reduce the measured overheating in the classrooms by 2-3 °C (indoor temperature should be below 23 °C) and maintain CO2 concentration under 900 ppm (the CO2 threshold is 1000 ppm), showing promising improvements to a classroom’s thermal condition and indoor air quality.

scholarly journals Carbon dioxide dynamics in an agricultural headwater stream driven by hydrology and primary production

2020 ◽  
Vol 17 (9) ◽  
pp. 2487-2498 ◽  
Author(s):  
Marcus B. Wallin ◽  
Joachim Audet ◽  
Mike Peacock ◽  
Erik Sahlée ◽  
Mattias Winterdahl
Keyword(s):  
Carbon Dioxide ◽  
Primary Production ◽  
Large Scale ◽  
Co2 Concentration ◽  
Base Flow ◽  
Concentration Data ◽  
Entire Study ◽  
Co2 Concentrations ◽  
Variable Nature ◽  
Co2 Dynamics

Abstract. Headwater streams are known to be hotspots for carbon dioxide (CO2) emissions to the atmosphere and are hence important components in landscape carbon balances. However, surprisingly little is known about stream CO2 dynamics and emissions in agricultural settings, a land use type that globally covers ca. 40 % of the continental area. Here we present hourly measured in situ stream CO2 concentration data from a 11.3 km2 temperate agricultural headwater catchment covering more than 1 year (in total 339 d excluding periods of ice and snow cover). The stream CO2 concentrations during the entire study period were generally high (median 3.44 mg C L−1, corresponding to partial pressures (pCO2) of 4778 µatm) but were also highly variable (IQR = 3.26 mg C L−1). The CO2 concentration dynamics covered a variety of different timescales from seasonal to hourly, with an interplay of hydrological and biological controls. The hydrological control was strong (although with both positive and negative influences dependent on season), and CO2 concentrations changed rapidly in response to rainfall and snowmelt events. However, during growing-season base flow and receding flow conditions, aquatic primary production seemed to control the stream CO2 dynamics, resulting in elevated diel patterns. During the dry summer period, rapid rewetting following precipitation events generated high CO2 pulses exceeding the overall median level of stream CO2 (up to 3 times higher) observed during the whole study period. This finding highlights the importance of stream intermittency and its effect on stream CO2 dynamics. Given the observed high levels of CO2 and its temporally variable nature, agricultural streams clearly need more attention in order to understand and incorporate these considerable dynamics in large-scale extrapolations.

scholarly journals Air quality in the eastern United States and Eastern Canada for 1990–2015: 25 years of change in response to emission reductions of SO<sub>2</sub> and NO<sub>x</sub> in the region

2019 ◽  
Author(s):  
Jian Feng ◽  
Elton Chan ◽  
Robert Vet
Keyword(s):  
Air Quality ◽  
Warm Season ◽  
Monitoring Network ◽  
Cold Season ◽  
Eastern United States ◽  
Eastern Canada ◽  
Spatial Changes ◽  
The Us ◽  
Clean Air ◽  
Uniform Reduction

Abstract. SO2 and NOx are precursors to form sulfate, nitrate and ammonium particles, which account for more than 50 % of PM2.5 mass in the eastern US and Eastern Canada, and are dominant components of PM2.5 during many smog events. H2SO4 and HNO3, formed from oxidation of SO2 and NOx respectively, are the main sources of acid deposition through wet and dry depositions. NOx is also a precursor to the formation of tropospheric O3, which is an important atmospheric oxidant and is also essential for the formation of other atmospheric oxidants, such as OH and H2O2. In the past 26 years from 1990 to 2015, emissions of SO2 and NOx in US were significantly reduced from 23.1 and 25.2 million tons/year in 1990 to 3.7 and 11.5 million tons/year in 2015 respectively. In Canada, SO2 and NOx were reduced by 63 % and 33 % from 1990 to 2014. In response to the significant reduction of SO2 and NOx emissions, air quality in the eastern US and Eastern Canada improved tremendously during 1990–2015. In this study, we analyzed surface air concentrations of SO42−, NO3−, NH4+, HNO3 and SO2 measured weekly by the Clean Air Status and Trends Network (CASTNET) in the US and measured daily from the Canadian Air and Precipitation Monitoring Network (CAPMoN) in Canada to reveal the temporal and spatial changes of each species during the 25-year period. For the whole the eastern US and Eastern Canada, the annual mean concentrations of SO42−, NO3−, NH4+, HNO3, SO2 and TNO3 (NO3− + HNO3, expressed as the mass of equivalent NO3−) were reduced by 73.3 %, 29.1 %, 67.4 %, 65.8 %, 87.6 % and 52.6 % respectively from 1990 to 2015. In terms of percentage, reduction of all species except NO3− was spatially uniform; reduction of SO2 and HNO3 was similar in warm season (May–October) and cold season (November–April), and reduction of SO42−, NO3− and NH4+ was more significant in warm season than in cold season. Reduction of SO42− and SO2 mainly occurred in 1989–1995 and 2007–2015 during warm season, and in 1989–1995 and 2005–2015 during cold season. Reduction of NO3− mainly occurred in the Midwest after 2000. Other than in the Midwest, NO3− had very little change during cold season for the period. The reduction of NH4+ generally followed the reduction trend of SO42−, especially after 2000 the temporal trend of NH4+ was almost identical to that of SO42−. The ratio of S in SO42− to total S in SO42− and SO2, as well as the ratio of NO3− to TNO3 increased by more than 50 % during the period. This indicates that much more percentage of SO2 was oxidized to SO42−, and much more percentage of HNO3 was neutralized to NH4NO3 in the region near the end of the period.

scholarly journals Method for Estimation of CO2 Gains from Persons in Builidings

Proceedings ◽  
2018 ◽  
Vol 2 (20) ◽  
pp. 1309 ◽  
Author(s):  
Antonio Rodero ◽  
Dorota Anna Krawczyk
Keyword(s):  
Carbon Dioxide ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Carbon Dioxide Concentration ◽  
Co2 Concentration ◽  
Males And Females ◽  
Sources Of Co2

Carbon dioxide concentration is an important parameter to know Indoor Air Quality of a building. One of the most important sources of CO2 in poor ventilated building is human activity. This work presents a method for experimental determination of human CO2 generation rate based on measuring of time evolution of indoor CO2 concentration. The method is applied to 5 rooms of an educational building from Bialystok (Poland). Similar carbon dioxide gains were obtained in all rooms, around 0.0046 L/s, which correspond to theoretical CO2 generation rates of a sedentary activity for persons, males and females, between 21–30 years old, characteristics of occupants of analyzed rooms.

scholarly journals Carbon Dioxide Footprint and Its Impacts: A Case of Academic Buildings

2021 ◽  
Vol 13 (14) ◽  
pp. 7847
Author(s):  
Muhammad Aashed Khan Abbasi ◽  
Shabir Hussain Khahro ◽  
Yasir Javed
Keyword(s):  
Carbon Dioxide ◽  
Carbon Emissions ◽  
Co2 Concentration ◽  
Automated System ◽  
Rapid Urbanization ◽  
Suggested Approach ◽  
Humidity Level ◽  
Co2 Concentrations ◽  
Academic Buildings ◽  
Academic Building

Carbon emissions have been considered a major reason behind climate change and global warming. Various studies report that rapid urbanization and the changing demands of 21st century life have resulted in higher carbon emissions. This study aims to examine the carbon footprints in an academic building to observe the carbon dioxide (CO2) levels at crucial landmarks and offices. A sensor-based automated system was designed and implemented for the collection of CO2 concentrations at selected locations. In the final stage, a CO2 footprint map was generated to highlight the vulnerable areas of CO2 in the academic building. It was concluded that offices have higher CO2 concentrations at both intervals (morning and afternoon), followed by the laboratory, corridors, and praying area. The CO2 concentration did not exceed 500 ppm at any location. Thus, all locations other than offices had normal CO2 concentration levels. Similarly, the humidity level was also satisfactory. The average humidity level was below 50%, which is below the permissible value of 65%. The recommended range for temperature values as per ASHRAE standards is 22.5 °C to 25.5 °C, except for prayer places. It was concluded that the selected academic institute is providing a good environment to the users of the building, but that may change once the academic institute becomes fully functional after COVID-19. This study assists the stakeholders in making guidelines and necessary actions to reduce CO2 concentration in academic buildings, as it is expected to rise once the human load increases in the next academic year. The suggested approach can be used in any other country and the results will vary based on the building type, building energy type, and building ventilation design.

scholarly journals Correlation of Respiratory Aerosols and Metabolic Carbon Dioxide

2021 ◽  
Vol 13 (21) ◽  
pp. 12203
Author(s):  
Niklas Kappelt ◽  
Hugo Savill Russell ◽  
Szymon Kwiatkowski ◽  
Alireza Afshari ◽  
Matthew Stanley Johnson
Keyword(s):  
Carbon Dioxide ◽  
Oral Fluid ◽  
Low Cost ◽  
Co2 Concentration ◽  
Transmission Route ◽  
Viral Loads ◽  
Co2 Concentrations ◽  
Carbon Dioxide Co2 ◽  
The Individual ◽  
Metabolic Carbon

Respiratory aerosols from breathing and talking are an important transmission route for viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies have found that particles with diameters ranging from 10 nm to 145 μm are produced from different regions in the respiratory system and especially smaller particles can remain airborne for long periods while carrying viral RNA. We present the first study in which respiratory aerosols have been simultaneously measured with carbon dioxide (CO2) to establish the correlation between the two concentrations. CO2 concentrations are easily available through low-cost sensors and could be used to estimate viral exposure through this correlation, whereas source-specific aerosol measurements are complicated and not possible with low-cost sensors. The increase in both respiratory aerosols and CO2 was linear over ten minutes in a 2 m3 chamber for all participants, suggesting a strong correlation. On average, talking released more particles than breathing, with 14,600 ± 16,800 min−1 (one-σ standard deviation) and 6210 ± 5630 min−1 on average, respectively, while CO2 increased with 139 ± 33 ppm min−1 during talking and 143 ± 29 ppm min−1 during breathing. Assuming a typical viral load of 7×106 RNA copies per mL of oral fluid, ten minutes of talking and breathing are estimated to produce 1 and 16 suspended RNA copies, respectively, correlating to a CO2 concentration of around 1800 ppm in a 2 m3 chamber. However, viral loads can vary by several orders of magnitude depending on the stage of the disease and the individual. It was therefore concluded that, by measuring CO2 concentrations, only the number and volume concentrations of released particles can be estimated with reasonable certainty, while the number of suspended RNA copies cannot.

scholarly journals Effect of Carbon dioxide (CO2) on mortality and reproduction of Anagasta kuehniella (Zeller 1879), in mass rearing, aiming at the production of Trichogramma spp.

2013 ◽  
Vol 85 (2) ◽  
pp. 823-831 ◽  
Author(s):  
ALOISIO COELHO JUNIOR ◽  
JOSE R.P. PARRA
Keyword(s):  
Carbon Dioxide ◽  
Egg Production ◽  
Co2 Concentration ◽  
Mass Rearing ◽  
High Density ◽  
Biological Parameters ◽  
Anagasta Kuehniella ◽  
Co2 Concentrations ◽  
Carbon Dioxide Co2

Eggs of Anagasta kuehniella (Zeller 1879) are widely used for mass rearing of Trichogramma spp. and other parasitoids and predators, largely commercialized in many countries. The aim of this study is to evaluate the effect of carbon dioxide (CO2) originated from larval metabolism on the biological parameters of A. kuehniella. For that purpose, we assess the production of carbon dioxide (CO2) per rearing tray of A. kuehniella and the effect of CO2 on the viability of egg-to-adult period and oviposition of A. kuehniella. Results allow to estimate that a rearing tray, containing 10,000 larvae between the 4th and 5th instars, produces an average of 30.67 mL of CO2 per hour. The highest egg production of A. kuehniella was obtained when the larvae were kept in rooms with lower concentration of CO2 (1,200 parts per million - ppm), producing 23% more eggs than in rooms with higher CO2 concentrations. In rooms with high density of trays (70 trays/room), CO2 concentration exceeded 4,400 ppm. The viability of the egg-to-adult period was not influenced by carbon dioxide.

scholarly journals EVALUATION OF LITHUANIAN AIR QUALITY MONITORING DATA APPLYING SYNOPTICAL ANALYSIS

2007 ◽  
Vol 15 (3) ◽  
pp. 173-181 ◽  
Author(s):  
Vilma Bimbaitė ◽  
Raselė Girgždienė
Keyword(s):  
Air Quality ◽  
Ozone Concentration ◽  
Warm Season ◽  
Cold Season ◽  
Quality Monitoring ◽  
Monitoring Data ◽  
Air Quality Monitoring ◽  
Ozone Level ◽  
Ozone Concentrations ◽  
Ozone Levels

Relationship between synoptical patterns and different pollutants was analysed in the study. Cases with ozone concentrations higher or equal to the 95th percentile of monthly ozone concentrations were analysed over the period 2002–2005. Ozone concentration cases were grouped into seven concentration intervals and analysed according to synoptical patterns (cold, warm and occluded fronts). Relationship between SO2, SO4 and NO2 and synoptical objects was analysed during warm and cold seasons. The influence of cold, warm and occluded fronts on the high ozone level formation are very similar at both Lithuanian rural stations of Preila and Rūgšteliškes. The influence of all the fronts was more significant during night hours at a relatively low (50–100 μg/m3) and high (>100 μg/m3) ozone levels during day hours. The concentrations of gaseous SO2, NO2 and aerosol SO4 pollutants for the cases with hourly ozone concentration values ≥95th percentile were analysed. The influence of different synoptical patterns was found to be stronger during a warm season and lower during a cold season of the year.

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