Assessing the Impact of Indoor Air Quality on Respiratory Health- Some Prescriptions

AbstractThe indoor environment is a major source of human exposure to pollutants. Some pollutants can have concentrations that are several times higher indoors than outdoors. Prolonged exposure may lead to adverse biologic effects, even at low concentrations. Several studies done in Malaysia had underlined the role of indoor air pollution in affecting respiratory health, especially for school-aged children. A critical review was conducted on the quantitative literature linking indoor air pollution with respiratory illnesses among school-aged children. This paper reviews evidence of the association between indoor air quality (IAQ) and its implications on respiratory health among Malaysian school-aged children. This review summarizes six relevant studies conducted in Malaysia for the past 10 years. Previous epidemiologic studies relevant to indoor air pollutants and their implications on school-aged children’s respiratory health were obtained from electronic database and included as a reference in this review. The existing reviewed data emphasize the impact of IAQ parameters, namely, indoor temperature, ventilation rates, indoor concentration of carbon dioxide (CO

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The impact of indoor air quality and contaminants on respiratory health of older people living in long-term care residences in Porto

Age and Ageing ◽

10.1093/ageing/afv157 ◽

2015 ◽

Vol 45 (1) ◽

pp. 136-142 ◽

Cited By ~ 10

Author(s):

Ana Mendes ◽

Ana Luísa Papoila ◽

Pedro Carreiro-Martins ◽

Stefano Bonassi ◽

Iolanda Caires ◽

...

Keyword(s):

Air Quality ◽

Older People ◽

Indoor Air Quality ◽

Indoor Air ◽

Long Term Care ◽

Respiratory Health ◽

Term Care ◽

The Impact

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

Sustainability ◽

10.3390/su13084139 ◽

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.

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Window operation behaviour and indoor air quality during lockdown: A monitoring-based simulation-assisted study in London

Building Services Engineering Research and Technology ◽

10.1177/01436244211017786 ◽

2021 ◽

pp. 014362442110177

Author(s):

Farhang Tahmasebi ◽

Yan Wang ◽

Elizabeth Cooper ◽

Daniel Godoy Shimizu ◽

Samuel Stamp ◽

...

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Energy Demand ◽

Natural Ventilation ◽

Probabilistic Models ◽

Performance Model ◽

Outdoor Environment ◽

Ventilation Strategies ◽

The Impact

The Covid-19 outbreak has resulted in new patterns of home occupancy, the implications of which for indoor air quality (IAQ) and energy use are not well-known. In this context, the present study investigates 8 flats in London to uncover if during a lockdown, (a) IAQ in the monitored flats deteriorated, (b) the patterns of window operation by occupants changed, and (c) more effective ventilation patterns could enhance IAQ without significant increases in heating energy demand. To this end, one-year’s worth of monitored data on indoor and outdoor environment along with occupant use of windows has been used to analyse the impact of lockdown on IAQ and infer probabilistic models of window operation behaviour. Moreover, using on-site CO2 data, monitored occupancy and operation of windows, the team has calibrated a thermal performance model of one of the flats to investigate the implications of alternative ventilation strategies. The results suggest that despite the extended occupancy during lockdown, occupants relied less on natural ventilation, which led to an increase of median CO2 concentration by up to 300 ppm. However, simple natural ventilation patterns or use of mechanical ventilation with heat recovery proves to be very effective to maintain acceptable IAQ. Practical application: This study provides evidence on the deterioration of indoor air quality resulting from homeworking during imposed lockdowns. It also tests and recommends specific ventilation strategies to maintain acceptable indoor air quality at home despite the extended occupancy hours.

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The impact of mechanical ventilation operation strategies on indoor CO2 concentration and air exchange rates in residential buildings

Indoor and Built Environment ◽

10.1177/1420326x20960767 ◽

2020 ◽

pp. 1420326X2096076

Author(s):

Pedro F. Pereira ◽

Nuno M. M. Ramos

Keyword(s):

Mechanical Ventilation ◽

Air Quality ◽

Exchange Rates ◽

Indoor Air Quality ◽

Indoor Air ◽

Residential Buildings ◽

Ventilation Strategy ◽

The Impact ◽

Mechanical Extraction ◽

Air Exchange

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.

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Indoor air quality improvement and purification by atmospheric pressure Non-Thermal Plasma (NTP)

Scientific Reports ◽

10.1038/s41598-021-02276-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Prince Junior Asilevi ◽

Patrick Boakye ◽

Sampson Oduro-Kwarteng ◽

Bernard Fei-Baffoe ◽

Yen Adams Sokama-Neuyam

Keyword(s):

Air Quality ◽

Built Environment ◽

Indoor Air Quality ◽

Removal Efficiency ◽

Indoor Air ◽

Thermal Plasma ◽

Processing Parameters ◽

Optimum Conditions ◽

Non Thermal Plasma ◽

The Impact

AbstractNon-thermal plasma (NTP) is a promising technology for the improvement of indoor air quality (IAQ) by removing volatile organic compounds (VOCs) through advanced oxidation process (AOP). In this paper, authors developed a laboratory scale dielectric barrier discharge (DBD) reactor which generates atmospheric NTP to study the removal of low-concentration formaldehyde (HCHO), a typical indoor air VOC in the built environment associated with cancer and leukemia, under different processing conditions. Strong ionization NTP was generated between the DBD electrodes by a pulse power zero-voltage switching flyback transformer (ZVS-FBT), which caused ionization of air molecules leading to active species formation to convert HCHO into carbon dioxide (CO2) and water vapor (H2O). The impact of key electrical and physical processing parameters i.e. discharge power (P), initial concentration (Cin), flow rate (F), and relative humidity (RH) which affect the formaldehyde removal efficiency (ɳ) were studied to determine optimum conditions. Results show that, the correlation coefficient (R2) of removal efficiency dependence on the processing parameters follow the order R2 (F) = 0.99 > R2 (RH) = 0.96, > R2 (Cin) = 0.94 > R2 (P) = 0.93. The removal efficiency reached 99% under the optimum conditions of P = 0.6 W, Cin = 0.1 ppm, F = 0.2 m3/h, and RH = 65% with no secondary pollution. The study provided a theoretical and experimental basis for the application of DBD plasma for air purification in the built environment.

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Impact of indoor air quality on respiratory health: results of a local survey on housing environment

Public Health ◽

10.1016/j.puhe.2018.06.015 ◽

2018 ◽

Vol 163 ◽

pp. 76-79 ◽

Cited By ~ 1

Author(s):

B. Lévesque ◽

V. Huppé ◽

M. Dubé ◽

R.C. Fachehoun

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Respiratory Health ◽

Housing Environment

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Efficiency and Eco-Costs of Air Purifiers in Terms of Improving Microbiological Indoor Air Quality in Dwellings—A Case Study

Atmosphere ◽

10.3390/atmos10120742 ◽

2019 ◽

Vol 10 (12) ◽

pp. 742 ◽

Cited By ~ 3

Author(s):

Ewa Brągoszewska ◽

Magdalena Bogacka ◽

Krzysztof Pikoń

Keyword(s):

Air Pollution ◽

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Pollution Prevention ◽

Average Concentration ◽

Environmental Cost ◽

Bacterial Aerosol ◽

The Impact ◽

Ecological Cost

Air pollution, a by-product of economic growth, generates an enormous environmental cost in Poland. The issue of healthy living spaces and indoor air quality (IAQ) is a global concern because people spend approximately 90% of their time indoors. An increasingly popular method to improve IAQ is to use air purifiers (APs). Indoor air is often polluted by bioaerosols (e.g., viruses, bacteria, fungi), which are a major concern for public health. This work presents research on culturable bacterial aerosol (CBA) samples collected from dwellings with or without active APs during the 2019 summer season. The CBA samples were collected using a six-stage Andersen cascade impactor (ACI). The CBA concentrations were expressed as Colony Forming Units (CFU) per cubic metre of air. The average concentration of CBA in dwellings when the AP was active was 450–570 CFU/m3, whereas the average concentration when the AP was not active was 920–1000 CFU/m3. IAQ, when the APs were active, was on average almost 50% better than in cases where there were no procedures to decrease the concentration of air pollutants. Moreover, the obtained results of the particle size distribution (PSD) of CBA indicate that the use of APs reduced the proportion of the respirable fraction (the particles < 3.3 µm) by about 16%. Life cycle assessment (LCA) was used to assess the ecological cost of air purification. Our conceptual approach addresses the impact of indoor air pollution on human health and estimates the ecological cost of APs and air pollution prevention policies.

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