Measured air exchange rates and indoor air quality in multifamily residences

1986 ◽  
Vol 9 (4) ◽  
pp. 293-303 ◽  
Author(s):  
G.B. Parker
2020 ◽  
pp. 1420326X2096076
Author(s):  
Pedro F. Pereira ◽  
Nuno M. M. Ramos

In Portugal, residential buildings commonly have their ventilation strategy changed after commissioning. This occurs due to the building managers' willingness to reduce shared costs with the electricity needed for fan operation. However, this option is not technically supported, and the effects of such a strategy on indoor air quality-related to human pollutants are yet to be quantified. CO2 was monitored in 15 bedrooms and air exchange rates were calculated for each room. The air exchange rate values ranged from 0.18 to 0.53 h−1 when mechanical extraction ventilation was off, and from 0.45 to 0.90 h−1 when mechanical extraction ventilation was on, which represents an average increase of 119%. With the current intermittent ventilation strategy, all rooms remain above 1500 ppm for a given percentage of time, and 12 rooms presenting CO2 concentrations above 2000 ppm. Simulations of theoretical CO2 concentrations, for a non-interrupted mechanical ventilation strategy show that no rooms would accumulate CO2 concentrations above 2000 ppm, and only 25% would present CO2 concentrations above 1500 ppm. Pearson correlations between the monitored CO2 and human and spatial factors identified two relevant parameters. Those parameters correspond to ratios between CO2 generation and floor area ([Formula: see text]), and airflow with CO2 generation ([Formula: see text]). The proposed ratios could be used as ways to optimise ventilation costs and indoor air quality.


1982 ◽  
Vol 8 (1-6) ◽  
pp. 435-445 ◽  
Author(s):  
F.J. Offermann ◽  
C.D. Hollowell ◽  
W.W. Nazaroff ◽  
G.D. Roseme ◽  
J.R. Rizzuto

Indoor Air ◽  
2013 ◽  
Vol 23 (4) ◽  
pp. 332-341 ◽  
Author(s):  
N. Shinohara ◽  
M. Tokumura ◽  
M. Kazama ◽  
H. Yoshino ◽  
S. Ochiai ◽  
...  

2014 ◽  
Vol 29 (suppl.) ◽  
pp. 52-58
Author(s):  
Franz Roessler ◽  
Jai Azzam ◽  
Volker Grimm ◽  
Hans Hingmann ◽  
Tina Orovwighose ◽  
...  

The energy conservation regulation provides upper limits for the annual primary energy requirements for new buildings and old building renovation. The actions required could accompany a reduction of the air exchange rate and cause a degradation of the indoor air quality. In addition to climate and building specific aspects, the air exchange rate is essentially affected by the residents. Present methods for the estimation of the indoor air quality can only be effected under test conditions, whereby the influence of the residents cannot be considered and so an estimation under daily routine cannot be ensured. In the context of this contribution first steps of a method are presented, that allows an estimation of the progression of the air exchange rate under favourable conditions by using radon as an indicator. Therefore mathematical connections are established that could be affirmed practically in an experimental set-up. So this method could provide a tool that allows the estimation of the progression of the air exchange rate and in a later step the estimation of a correlating progression of air pollutant concentrations without limitations of using the dwelling.


Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7202
Author(s):  
Yue Deng ◽  
Mark Sprowls ◽  
S. Jimena Mora ◽  
Doina Kulick ◽  
Nongjian Tao ◽  
...  

This work investigates the use of an intelligent and unobstructive sensing technique for maintaining vehicle cabin’s indoor air quality while simultaneously assessing the driver metabolic rate. CO2 accumulation patterns are of great interest because CO2 can have negative cognitive effects at higher concentrations and also since CO2 accumulation rate can potentially be used to determine a person’s metabolic rate. The management of the vehicle’s ventilation system was controlled by periodically alternating the air recirculation mode within the cabin, which was actuated based on the CO2 levels inside the vehicle’s cabin. The CO2 accumulation periods were used to assess the driver’s metabolic rate, using a model that considered the vehicle’s air exchange rate. In the process of the method optimization, it was found that the vehicle’s air exchange rate (λ [h−1]) depends on the vehicle speeds, following the relationship: λ = 0.060 × (speed) − 0.88 when driving faster than 17 MPH. An accuracy level of 95% was found between the new method to assess the driver’s metabolic rate (1620 ± 140 kcal/day) and the reference method of indirect calorimetry (1550 ± 150 kcal/day) for a total of N = 16 metabolic assessments at various vehicle speeds. The new sensing method represents a novel approach for unobstructive assessment of driver metabolic rate while maintaining indoor air quality within the vehicle cabin.


Author(s):  
V. Deshko ◽  
I. Bilous ◽  
I. Sukhodub ◽  
O. Yatsenko

Modern results of Ukrainian buildings energy analysis show that 30-50% of the energy for heating goes to heat the supply air, and that is the largest share in the building energy balance. In terms of energy consumption, efficiency of the air exchange mode largely depends on occupancy schedule and air distribution in time and space. The application of air exchange schedule approach makes more sense in case when individual heating control is carried out. Therefore, during occupied hours, the comfortable ventilation level can be ensured, and, during unoccupied hours, it can be reduced to a minimum. According to the results of the study, the use of intermittent air exchange mode in the studied apartment on weekdays, leads to decrease in energy consumption compared to constant air exchange at the level of upper values of the ventilation schedule. In terms of energy efficiency, the use of the constant air change rate from ASHRAE Std 62 is the most efficient approach. In terms of indoor air quality and concentration of CO2 and VOCs, the scheduled air exchange approach with increased air change rates (from EN 16798) during occupied hours is more efficient. Therefore, the use of required and experimental air change rate values to create the hourly schedules allows to define more precisely a building energy consumption and to choose an optimal operation schedule for building engineering systems to provide thermal comfort and indoor air quality during occupied hours.


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