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Starting in the 1970s, individuals, businesses and the public have increasingly benefited from policies prohibiting smoking indoors, saving thousands of lives and billions of dollars in healthcare expenditures. Smokefree policies to protect against secondhand smoke exposure, however, do not fully protect the public from the persistent and toxic chemical residues from tobacco smoke (also known as thirdhand smoke) that linger in indoor environments for years after smoking stops. Nor do these policies address the economic costs that individuals, businesses and the public bear in their attempts to remediate this toxic residue. We discuss policy-relevant differences between secondhand smoke and thirdhand smoke exposure: persistent pollutant reservoirs, pollutant transport, routes of exposure, the time gap between initial cause and effect, and remediation and disposal. We examine four policy considerations to better protect the public from involuntary exposure to tobacco smoke pollutants from all sources. We call for (a) redefining smokefree as free of tobacco smoke pollutants from secondhand and thirdhand smoke; (b) eliminating exemptions to comprehensive smoking bans; (c) identifying indoor environments with significant thirdhand smoke reservoirs; and (d) remediating thirdhand smoke. We use the case of California as an example of how secondhand smoke-protective laws may be strengthened to encompass thirdhand smoke protections. The health risks and economic costs of thirdhand smoke require that smokefree policies, environmental protections, real estate and rental disclosure policies, tenant protections, and consumer protection laws be strengthened to ensure that the public is fully protected from and informed about the risks of thirdhand smoke exposure.

BACKGROUND: Diesel exhaust (DE) exposures pose concerns for serious health effects, including asthma and lung cancer, in California communities burdened by multiple stressors. OBJECTIVE: To evaluate DE exposures in disproportionately impacted communities using biomonitoring and compare results for adults and children within and between families. METHODS: We recruited 40 families in the San Francisco East Bay area. Two metabolites of 1-nitropyrene (1-NP), a marker for DE exposures, were measured in urine samples from parent-child pairs. For 25 families, we collected single-day spot urine samples during two sampling rounds separated by an average of four months. For the 15 other families, we collected daily spot urine samples over four consecutive days during the two sampling rounds. We also measured 1-NP in household dust and indoor air. Associations between urinary metabolite levels and participant demographics, season, and 1-NP levels in dust and air were evaluated. RESULTS: At least one 1-NP metabolite was present in 96.6% of the urine samples. Detection frequencies for 1-NP in dust and indoor air were 97% and 74%, respectively. Results from random effect models indicated that levels of the 1-NP metabolite 6-hydroxy-1-nitropyrene (6-OHNP) were significantly higher in parents compared with their children (p-value = 0.005). Urinary 1-NP metabolite levels were generally higher during the fall and winter months. Within-subject variability was higher than between-subject variability (~60% of total variance versus ~40%, respectively), indicating high short-term temporal variability. IMPACT: Biomonitoring, coupled with air monitoring, improves understanding of hyperlocal air pollution impacts. Results from these studies will inform the design of effective exposure mitigation strategies in disproportionately affected communities.

Because humans spend about one-third of their time asleep in their bedrooms and are themselves emission sources of volatile organic compounds (VOCs), it is important to specifically characterize the composition of the bedroom air that they experience during sleep. This work uses real-time indoor and outdoor measurements of volatile organic compounds (VOCs) to examine concentration enhancements in bedroom air during sleep and to calculate VOC emission rates associated with sleeping occupants. Gaseous VOCs were measured with proton-transfer reaction time-of-flight mass spectrometry during a multiweek residential monitoring campaign under normal occupancy conditions. Results indicate high emissions of nearly 100 VOCs and other species in the bedroom during sleeping periods as compared to the levels in other rooms of the same residence. Air change rates for the bedroom and, correspondingly, emission rates of sleeping-associated VOCs were determined for two bounding conditions: (1) air exchange between the bedroom and outdoors only and (2) air exchange between the bedroom and other indoor spaces only (as represented by measurements in the kitchen). VOCs from skin oil oxidation and personal care products were present, revealing that many emission pathways can be important occupant-associated emission factors affecting bedroom air composition in addition to direct emissions from building materials and furnishings.

We need human behavioural change to decarbonize our buildings. This requirement arises from our needs, lifestyle energy choices and interactions with buildings, and is an underexploited, yet essential demand-side opportunity for rapid and sustainable decarbonization. We propose a sufficiency-oriented approach that fosters equitable building decarbonization, while maintaining planetary boundaries.

Thirdhand smoke (THS) is the persistent and toxic residue from tobacco smoke in indoor environments. A comprehensive understanding of the chemical constituents of THS is necessary to assess the risks of long-term exposure and to establish reliable THS tracers. The objective of this study was to investigate compounds associated with THS through nontargeted analysis (NTA) of settled house dust samples from smokers' and non-smokers' homes, using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC/TOF-MS). Compounds that were either only present in dust from smokers' homes or that had significantly larger abundance than in non-smokers' homes were termed qualified compounds. We identified 140 qualified compounds, and of these, 42 compounds were tentatively identified by searching matching mass spectra in NIST electron impact (EI) mass spectral library including 20 compounds confirmed with their authentic standards. Among the 42 compounds, 26 compounds were statistically more abundant (p

Future climate change can cause more days with poor air quality. This could trigger more alerts telling people to stay inside to protect themselves, with potential consequences for health and health equity. Here, we study the change in US air quality alerts over this century due to fine particulate matter (PM2.5), who they may affect, and how they may respond. We find air quality alerts increase by over 1 mo per year in the eastern United States by 2100 and quadruple on average. They predominantly affect areas with high Black populations and leakier homes, exacerbating existing inequalities and impacting those less able to adapt. Reducing emissions can offer significant annual health benefits ($5,400 per person) by mitigating the effect of climate change on air pollution and its associated risks of early death. Relying on people to adapt, instead, would require them to stay inside, with doors and windows closed, for an extra 142 d per year, at an average cost of $11,000 per person. It appears likelier, however, that people will achieve minimal protection without policy to increase adaptation rates. Boosting adaptation can offer net benefits, even alongside deep emission cuts. New adaptation policies could, for example: reduce adaptation costs; reduce infiltration and improve indoor air quality; increase awareness of alerts and adaptation; and provide measures for those working or living outdoors. Reducing emissions, conversely, lowers everyones need to adapt, and protects those who cannot adapt. Equitably protecting human health from air pollution under climate change requires both mitigation and adaptation.

BACKGROUND: In low- and middle-income countries countries, millions of deaths occur annually from household air pollution (HAP), pulmonary tuberculosis (PTB), and HIV-infection. However, it is unknown whether HAP influences PTB risk among people living with HIV-infection. METHODS: We conducted a case-control study among 1,277 HIV-infected adults in Bukavu, eastern Democratic Republic of Congo (February 2018 - March 2019). Cases had current or recent (3h/day and ≥2 times/day and ≥5 days/week were more likely to have PTB (aOR 1·36; 95%CI 1·06-1·75) than those spending less time in the kitchen. Time-weighted average 24h personal CO exposure was related dose-dependently with the likelihood of having PTB, with aOR 4·64 (95%CI 1·1-20·7) for the highest quintile [12·3-76·2 ppm] compared to the lowest quintile [0·1-1·9 ppm]. CONCLUSION: Time spent cooking and personal CO exposure were independently associated with increased risk of PTB among people living with HIV. Considering the high burden of TB-HIV coinfection in the region, effective interventions are required to decrease HAP exposure caused by cooking with biomass among people living with HIV, especially women.

Background: The indoor home environment plays a crucial role in determining the outcome of respiratory diseases, including asthma. Researchers, clinicians, and patients would benefit from self-reported questionnaires to assess indoor home environmental exposures that may impact on respiratory health. Objective: To review self-reported instruments for assessing indoor home environmental exposures in asthma patients and to characterise their content, development, and psychometric properties. Design: A scoping review was conducted with content assessment. Methods: A literature search was conducted in Embase and PubMed using the key words housing quality, questionnaire and asthma and their index terms, covering articles published in English between January 2000 to July 2023. Articles in which questionnaires or single item questions were used to assess indoor home environmental exposures in asthma patients in middle- and high-income countries were included. We excluded articles in which the questionnaire required an interviewer or onsite observations and those conducted in low-income countries. Results: We screened 1584 articles to identify 44 studies containing self-reported questionnaires measuring indoor home environmental exposures. 36 studies (82%) were cross sectional, 35 (80%) had a sample size of greater than 1000 participants, and 29 (66%) were conducted in children. Most studies (86%, n = 38) had binary (yes/no) or multiple-choice responses. 25 studies (57%) included a recall period of 12 months. 32 studies (73%) had a response rate of greater than 50%. Dampness, biological exposures (e.g. mould), and second-hand tobacco smoke were the most assessed indoor home environmental exposures. Childhood asthma (54%, n = 24) and asthma symptoms (36%, n = 16) were the most examined asthma related outcomes. The exposure most associated with adverse asthma outcomes was exposure to damp (79%, n = 35). 13 studies (29%) had developed a self-reported instrument by adapting questions from previous studies and almost all instruments (n = 42 studies, 95%) had not been validated. Conclusions: The scoping review did not identify a comprehensive, validated self-reported questionnaire for assessing indoor home environmental exposures in patients with asthma. There is need to develop and validate a robust but pragmatic self-reported instrument, incorporating the findings from this review. Lay summary: Background: The home environment significantly affects respiratory diseases like asthma. To help researchers, doctors, and patients, there is a need for instruments that people can use to report environmental factors at home that might influence their asthma. Objective: The aim was to review self-reported instruments that asthma patients use to assess their home environments. The review looked at what these instruments measured, how they were developed, and how reliable they were. Design: The study used a scoping review, which provides an overview of the available evidence, and assessed the content of existing questionnaires. Methods: Researchers searched scientific articles in two major databases, Embase and PubMed. They looked for articles in English published since 2000. They included studies from middle- and high-income countries where people filled out questionnaires about their home environment's impact on asthma. They excluded studies needing an interviewer or on-site visits and those from low-income countries. Results: From 1584 articles, 44 studies were selected. Most studies (82%) were cross-sectional, meaning they looked at data from a single point in time. Four out of five studies included more than 1000 participants, and two thirds involved children. The questionnaires often had yes/no or multiple-choice questions and usually asked about conditions over the past year or more. Common topics were dampness, exposure to mould, and second-hand smoke. Almost three quarters of studies received a response from more than half of the participants they asked. Dampness was the factor most linked to worsening asthma. While many studies adapted questions from previous research, only one in 20 reported how they validated their questionnaires. Conclusions: The review did not find a single, well-validated questionnaire for assessing home environments in asthma patients. There is a need to develop a reliable and practical instrument based on these findings. [ABSTRACT FROM AUTHOR]

An all‐flexible self‐powering unit, combining a flexible perovskite solar mini‐module for energy conversion and ultra‐flexible screen‐printed interdigitated carbon supercapacitors on paper for energy storage, is designed and developed. Through a hybrid bifurcated structure, the supercapacitors are connected in series and neatly layered on a paper substrate with the perovskite solar mini‐module strategically placed on top for seamless integration. The photosupercapacitor quickly reaches saturated voltage under various light intensities (1 sun, 1000 lx, 500 lx, and 200 lx) and displays a self‐discharge time of over 2 minutes. It delivers peak overall and storage efficiencies of 2.8% and 23%, respectively, and exhibits an extensive potential window of 3.8 V, making it a prominent choice for real time applications in electronic systems. In a nutshell, the inherent flexibility of both the solar module and the storage system, coupled with the space‐saving design, and the extensive potential window of the hybrid photosupercapacitor paves the way for implementation in portable and wearable electronics operating in indoor environments, ushering a new era of more versatile and adaptable energy solutions. [ABSTRACT FROM AUTHOR]

Understanding the neural responses to indoor characteristics like temperature and light is crucial for comprehending how the physical environment influences the human brain. Our study introduces an innovative approach using entropy analysis, specifically, approximate entropy (ApEn), applied to electroencephalographic (EEG) signals to investigate neural responses to temperature and light variations in indoor environments. By strategically placing electrodes over specific brain regions linked to temperature and light processing, we show how ApEn can be influenced by indoor factors. We also integrate heart indices from a multi-sensor bracelet to create a machine learning classifier for temperature conditions. Results showed that in anterior frontal and temporoparietal areas, neutral temperature conditions yield higher ApEn values. The anterior frontal area showed a trend of gradually decreasing ApEn values from neutral to warm conditions, with cold being in an intermediate position. There was a significant interaction between light and site factors, only evident in the temporoparietal region. Here, the neutral light condition had higher ApEn values compared to blue and red light conditions. Positive correlations between anterior frontal ApEn and thermal comfort scores suggest a link between entropy and perceived thermal comfort. Our quadratic SVM classifier, incorporating entropy and heart features, demonstrates strong performance (until 90% in terms of AUC, accuracy, sensitivity, and specificity) in classifying temperature sensations. This study offers insights into neural responses to indoor factors and presents a novel approach for temperature classification using EEG entropy and heart features. [ABSTRACT FROM AUTHOR]

Background: Understanding the impact of intervention tools on vector behaviour, host preference, resting, and infectivity rates is paramount in malaria control planning. Magu district was one of the districts in lake zone regions in northwestern Tanzania covered with indoor residual spray and long-lasting insecticidal nets in the main malaria control campaign. After interventions, this study evaluated the mosquito's host preference and resting behaviour in Lugeye village in rainy and dry seasons. Methods: Mosquitoes were collected both indoors and outdoors using the rest pots. The collection was done in both rainy and dry seasons. The samples were collected bi-weekly for three months each season. Results: A total of 254 mosquitoes were collected in both dry and rainy seasons, indoors and outdoors. The most abundant species were Anopheles funestus s.s. and An.arabiensis. Most blood meals from bovines rested outdoors, while human blood meal sources rested outdoors. Sporozoite-positive mosquitoes were found only during the dry season. Conclusion: This study's findings have shown that implementing IRS and LLIN interventions has led to a species shift from An.gambiae s.s. to An.funestus and An.arabiensis. The inclusion of vector insecticide resistance information can be of paramount importance in appropriate intervention tool selection. [ABSTRACT FROM AUTHOR]

Introduction: Indoor air pollution, causing health issues like Sick Building Syndrome (SBS), is the third largest global contributor to disability-adjusted life years, emphasizing the urgent need for improved indoor air quality. This study aimed to determine the association between Indoor Air Quality (IAQ) and SBS among workers at food outlets in Selangor, Malaysia. Methods: A cross-sectional study was carried out among 107 workers in mall, new and old food outlet. A set of standardized and validated version questionnaires of the Industry Code of Practice on Indoor Air Quality (ICOP IAQ) 2010 was distributed to obtain respondents' sociodemographic information, symptoms present at the workplace, and psychosocial information. Results and Discussion: The study found significant differences in temperature (p = 0.004), air velocity (p = 0.037), ultrafine particles (p = 0.005), and carbon dioxide (CO2) concentrations (p = 0.006) in malls, new and old food outlets. Workers in old food outlets had the highest prevalence of SBS (66.7%), compared to those in new outlets (60.5%) and mall outlets (64.7%). Environmental characteristics, such as increased dust and particulate matter during renovation (OR = 6.17, 95% CI = 1.34- 28.34), repair (OR = 2.43, 95% CI = 1.03-5.76), along with temperature variations (OR = 7.21, 95% CI = 2.52-20.66) significantly influencing SBS. Conclusion: SBS prevalence in food outlets is not significantly linked to IAQ parameters, but exposure to UFP and PM2.5 may contribute to its development. However, it is significantly associated with workplace renovations and repairs for interior design, as well as varying temperatures. [ABSTRACT FROM AUTHOR]

Despite advancements in the industry, safety investments at small construction sites remain underinvested due to budget constraints that limit the employment of safety managers. The results of this study explore a cost-effective solution for accurate positioning of workers in hazardous areas using off-the-shelf smartphones and Ultra-Wide Band (UWB) technology, with a focus on small and medium-sized construction sites. We targeted a Three-Dimensional (3D) positioning error of less than 35 cm in an indoor space of 25–50 m2. The results show that the spatial configuration of anchors and Mobile Terminals (MTs) has a significant impact on 3D accuracy, and in particular, deployment strategies with increasing height differences show a clearer reduction in error than differences in positional accuracy caused by differences between general least square algorithms. This highlights the importance of optimal anchor-MT placement, similar to Global Navigation Satellite System (GNSS) standards, to minimize Position Dilution of Precision (PDOP) values and improve positioning accuracy. We also suggest that adjusting the tetrahedral volume formed by anchors and MTs can solve complex site problems,improve worker positioning, and benefit safety management. This approach presents a practical and scalable way to improve safety protocols on small construction sites. [ABSTRACT FROM AUTHOR]

Air pollution has been a significant environmental and public health concern in Ulaanbaatar, the capital city of Mongolia, for many years. The city experiences severe air pollution, particularly during the winter months. This study investigated the annual trends of outdoor and indoor PM2.5 concentrations at two neighboring sites in Ulaanbaatar: an office and a household, using low-cost sensors. Both locations exhibited similar fluctuations in outdoor PM2.5 concentrations over time, with ambient PM2.5 levels beginning to rise in October and declining in April. During the mid-term of the heating season (November to February), hourly averaged PM2.5 concentrations were exceptionally high, with peak pollution events exceeding ~ 1000 µg/m3. Notably, PM2.5 concentrations were elevated during this heating season period. Time-activity patterns showed a decrease in PM2.5 concentrations during the periods of 06:00–08:00 and 14:00–18:00. Furthermore, the study found that the indoor environment could remain safe when windows were well-sealed, even under severe outdoor pollution conditions. Overall, this study provided accurate insights into the annual patterns of PM2.5 concentrations and demonstrated their fluctuations during the heating season when pollution levels were particularly high. The findings offer valuable recommendations for individuals to consider when going outside and for taking actions to improve indoor air quality in Ulaanbaatar. [ABSTRACT FROM AUTHOR]

Summary: This paper presents two different configurations of ±45° dual‐wideband dual‐polarized (DWDP) antennas. The antenna comprises eight end‐loaded broadband dipoles grouped into two sets based on the bands of operation. The high‐frequency dipoles are strategically placed within the low‐frequency ones to form the elementary unit. Further optimization has been performed on the elementary unit in terms of the radiator placement to suppress sidelobe levels for array formation. Both configurations are meticulously fabricated using an all‐metal structure, demonstrating durability and the simplicity of fabrication. The antenna designs achieve ±45° polarization, high gain, satisfactory cross‐polarization discrimination (XPD), and wide impedance bandwidth covering 0.67–1.04 GHz and 1.54–3 GHz bands. Despite the nested configuration, mutual coupling is well within acceptable limits. Formation of the array based on the optimum elementary unit has been investigated by simulation, revealing reasonable gain enhancement and low sidelobe levels across all bands. This comprehensive approach yields a robust, high‐performing antenna configuration suitable for indoor distributed antenna system (IDAS) applications. [ABSTRACT FROM AUTHOR]

Hydrogen, with its unique flammability characteristics, demands additional consideration due to its broader flammable range compared to fossil fuels. Its low density at atmospheric conditions results in significant buoyancy, mitigating risks in outdoor applications. In confined spaces, hydrogen releases can lead to flammable cloud formation. To study this problem, independent of its dimensions, a dimensional analysis is introduced based on Buckingham's Π -theorem. This work focuses on thirteen functional parameters, including mole fraction, time, release velocity, orifice diameter, reduced gravity, molecular mass diffusion, viscosity and geometric dimensions. Four dimensional scenarios are simulated and compared in this study, to assess the adequacy of the proposed non-dimensional approach. The setup involves a parallelepiped enclosure with a single release point. RANS simulations are conducted. The proposed non-dimensional formulation proves valuable for interpreting data and discussing practical applications. The study contributes to a deeper understanding of hydrogen filling regimes in confined spaces, offering insights for safety assessments and risk mitigation strategies. [Display omitted] • Functional parameters for hydrogen distribution are proposed. • Application of Buckingham's Π -theorem yields essential non-dimensional ratios. • RANS CFD-model used to simulate and discuss four similar scenarios. • Time series analysis of non-dimensional flammable volume reveals similarity. • Ratios and non-dimensional flammable volume enable dimension-independent safety analysis. [ABSTRACT FROM AUTHOR]

Vertebrate scavenging on human remains is occasionally observed at indoor forensic scenes, especially when pets have access to the body and their deceased owners were socially distanced. Pets feeding on corpses have implications for the forensic investigation, e.g. for trauma analysis and the assessment of the cause of death, the estimation of the postmortem interval (PMI), or the recovery of the complete set of remains. Documentation of potential scavenging in forensic practice is tenuous and needs to be improved in order to be able to use the information for future casework. Investigators need to be aware of the alterations pets can cause to human remains and how these affect further analyses. Following a combined literature review for cat and canine scavenging, we present seven new cases from Switzerland with cat and/or dog involvement. We then created a flowchart guide for a systematic collection of data to use at indoor forensic scenes of suspected scavenging. Our literature review revealed the challenge in discriminating between scavenging by domestic cats and dogs, based on the appearance of the lesions alone. Furthermore, the information that is often routinely collected in indoor fatalities with potential scavenging activity is not sufficient to perform this separation. To provide a practical basis for cat and canine scavenging and its differentiation, we summarise strategies and present a flowchart to use in forensic casework of suspected indoor scavenging. [ABSTRACT FROM AUTHOR]

Understanding the biting behaviour of vectors is essential for determining their vectorial potential and, hence, their role in disease transmission. The study was a two-year entomological survey of malaria vectors in three agrarian communities of Kano state designated as large irrigation (LIC), urban irrigation (UIC) and nonirrigation (NIC) communities. Human-baited Centre for Disease Control (CDC) light traps collected outdoor and indoor biting adult mosquitoes overnight. The collected female Anopheles species were morphologically identified to the species level using standard keys. A total of six hundred and thirty-seven (637) female Anopheles species were trapped of which 322 (50.55%) were collected indoors and 315 (49.45%) were collected outdoors. LIC and NIC had more Anopheles mosquitoes collected outdoors (51.08% and 66.04% respectively) than indoors (48.92% and 33.96% respectively) while UIC had more Anopheles mosquitoes collected indoors (67.77%) than outdoors (32,23%). Mosquito biting activity was higher in the wet season than in the dry season but did not differ significantly indoors (F-value = 3.310, p = 0.84) and outdoors (F = 0.651, p = 0.532). Statistical differences were recorded in the mean outdoor Anopheles abundance (F = 4.51 and p = 0.044) across the communities. Single, bimodal, and multiple biting peaks were observed in the study. Early biting peaks (1800-1900 hours) were observed outdoors (wet season) in NIC and indoors in UIC (dry season). The early outdoor biting activities of Anopheles species established in this study suggest the possibility of continued malarial transmission despite household use of bed nets. This implies that this control measure might be insufficient for malaria control in the region, and thus integrated methods for controlling malaria vectors should be considered. [ABSTRACT FROM AUTHOR]

Accurate fire ignition spatial location methods can serve the automatic fire suppression based on video. Although current fire detection systems based on monocular surveillance videos can quickly detect fires, it is impossible to obtain the 3D position due to the polysemy of 2D images. To further promote the universal application of automatic fire suppression, we propose a 3D indoor fire ignition location method based on monocular vision. This is the first study on spatial orientation of fire based on monocular vision. First, the indoor scene is quickly reconstructed as the basis of the scene. Second, based on our previous research on fire detection, the refined position of the fire in 2D images and its topological relationship with the space object are analyzed. The hierarchical constraints from 2 to 3D are established for the spatial orientation of the indoor fire ignition point. The experimental results show that the average absolute error is only 4.82 cm and that the average relative error is 1.71%. In addition, our method can be embedded into the existing fire prevention and control system at a low cost, further promoting the development of intelligent fire prevention and control. [ABSTRACT FROM AUTHOR]

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Building conditions, outdoor climate, and human behavior influence residential concentrations of fine particulate matter (PM2.5). To study PM2.5 spatiotemporal variability in residences, we acquired paired indoor and outdoor PM2.5 measurements at 3,977 residences across the United States totaling >10,000 monitor-years of time-resolved data (10-min resolution) from the PurpleAir network. Time-series analysis and statistical modeling apportioned residential PM2.5 concentrations to outdoor sources (median residential contribution = 52% of total, coefficient of variation = 69%), episodic indoor emission events such as cooking (28%, CV = 210%) and persistent indoor sources (20%, CV = 112%). Residences in the temperate marine climate zone experienced higher infiltration factors, consistent with expectations for more time with open windows in milder climates. Likewise, for all climate zones, infiltration factors were highest in summer and lowest in winter, decreasing by approximately half in most climate zones. Large outdoor-indoor temperature differences were associated with lower infiltration factors, suggesting particle losses from active filtration occurred during heating and cooling. Absolute contributions from both outdoor and indoor sources increased during wildfire events. Infiltration factors decreased during periods of high outdoor PM2.5, such as during wildfires, reducing potential exposures from outdoor-origin particles but increasing potential exposures to indoor-origin particles. Time-of-day analysis reveals that episodic emission events are most frequent during mealtimes as well as on holidays (Thanksgiving and Christmas), indicating that cooking-related activities are a strong episodic emission source of indoor PM2.5 in monitored residences.

The use of household bleach cleaning products results in emissions of highly oxidative gaseous species, such as hypochlorous acid (HOCl) and chlorine (Cl2). These species readily react with volatile organic compounds (VOCs), such as limonene, one of the most abundant compounds found in indoor enviroments. In this study, reactions of HOCl/Cl2 with limonene in the gas phase and on indoor relevant surfaces were investigated. Using an environmental Teflon chamber, we show that silica (SiO2), a proxy for window glass, and rutile (TiO2), a component of paint and self-cleaning surfaces, act as a reservoir for adsorption of gas-phase products formed between HOCl/Cl2 and limonene. Furthermore, high-resolution mass spectrometry (HRMS) shows that the gas-phase reaction products of HOCl/Cl2 and limonene readily adsorb on both SiO2 and TiO2. Surface-mediated reactions can also occur, leading to the formation of new chlorine- and oxygen-containing products. Transmission Fourier-transform infrared (FTIR) spectroscopy of adsorption and desorption of bleach and terpene oxidation products indicates that these chlorine- and oxygen-containing products strongly adsorb on both SiO2 and TiO2 surfaces for days, providing potential sources of human exposure and sinks for additional heterogeneous reactions.

Abstract Background The indoor home environment plays a crucial role in determining the outcome of respiratory diseases, including asthma. Researchers, clinicians, and patients would benefit from self-reported questionnaires to assess indoor home environmental exposures that may impact on respiratory health. Objective To review self-reported instruments for assessing indoor home environmental exposures in asthma patients and to characterise their content, development, and psychometric properties. Design A scoping review was conducted with content assessment. Methods A literature search was conducted in Embase and PubMed using the key words housing quality, questionnaire and asthma and their index terms, covering articles published in English between January 2000 to July 2023. Articles in which questionnaires or single item questions were used to assess indoor home environmental exposures in asthma patients in middle- and high-income countries were included. We excluded articles in which the questionnaire required an interviewer or onsite observations and those conducted in low-income countries. Results We screened 1584 articles to identify 44 studies containing self-reported questionnaires measuring indoor home environmental exposures. 36 studies (82%) were cross sectional, 35 (80%) had a sample size of greater than 1000 participants, and 29 (66%) were conducted in children. Most studies (86%, n = 38) had binary (yes/no) or multiple-choice responses. 25 studies (57%) included a recall period of 12 months. 32 studies (73%) had a response rate of greater than 50%. Dampness, biological exposures (e.g. mould), and second-hand tobacco smoke were the most assessed indoor home environmental exposures. Childhood asthma (54%, n = 24) and asthma symptoms (36%, n = 16) were the most examined asthma related outcomes. The exposure most associated with adverse asthma outcomes was exposure to damp (79%, n = 35). 13 studies (29%) had developed a self-reported instrument by adapting questions from previous studies and almost all instruments (n = 42 studies, 95%) had not been validated. Conclusions The scoping review did not identify a comprehensive, validated self-reported questionnaire for assessing indoor home environmental exposures in patients with asthma. There is need to develop and validate a robust but pragmatic self-reported instrument, incorporating the findings from this review.

Background: Research on the relationship between bioaerosols and particulate matter (PM) concentrations is necessary, especially in hospitals where airborne bioaerosols can facilitate disease transmission. This study aimed to investigate the relationship between PM (PM2.5 and PM10) and bioaerosols, as well as the factors influencing them (temperature and humidity), in the air of liver transplant operating rooms (LTOR) at Imam Khomeini Hospital in Tehran. Methods: Bioaerosol samples (32 samples) were collected using the passive sampling method, employing open-door plates containing culture medium, during June and July of 2019. PM samples were obtained concurrently with bioaerosol samples using the GM8803 air quality detector, during four one-hour periods. Simple linear regression analysis was performed to determine the relationship between bioaerosol and PM concentrations. Results: It was revealed that the average concentrations of PM2.5 and PM10 were 17.8 (SD = 2.2) and 27.0 (SD = 2.6) μg/m3, respectively. Additionally, the average concentrations of bacterial and fungal bioaerosols were 2132 (SD = 837) and 550 (SD = 189.4) CFU/m2.h, respectively. Linear regression analysis demonstrated a strong correlation between bacterial bioaerosols and PM concentrations, whereas the relationship with fungal bioaerosols was relatively weaker. Conclusion: The findings of this study indicate that the indoor air in LTOR exhibits a higher level of microbial contamination than the recommended guidelines for high-risk environments. To improve the air quality in LTOR, it is recommended to implement periodic microbial monitoring, ensure the proper functioning of ventilation systems, and pay attention to their maintenance and operation.

Optimal lighting design for the rooms used by children with special needs requires a consideration of the psychological and aesthetic effects on these children. Lighting design in general is the process of integrating light into architecture to provide comfort, safety, and aesthetics. When designing lighting for children with special needs, certain criteria and considerations must be set out to ensure that the design matches the children’s needs. The interior designer must apply the appropriate scientific methods and systems to reach the desired psychological and aesthetic goals; this process includes studying the basic criteria for designing light and using modern optical systems to reach the best results, according to the children’s activity inside the room, with the possibility of applying standards, considerations and laws related to light to develop basic suggestions for the design of interior lighting. The aim of this research is to determine the best techniques, methods, and standards of lighting for the rooms of children with special needs. It evaluates practices and latest technologies related to the process of designing interior lighting for children with special needs, including lighting that allows them to accomplish their tasks while also feeling safe. The research method depends on the descriptive analysis by studying the principles of both natural and artificial lighting and their standards and considerations, followed by the statistical analysis by modeling two different spaces for children with special need: a private bedroom and a public space for activities in which children with different disabilities can interact. A questionnaire was used to explore the opinion of specialists in the field of interior design about the two different modeled spaces. The results shows that good lighting design can provide ease of functionality with a sense of comfort and safety, meanwhile achieves the aesthetics of the interior design. The employment of artificial lighting with natural lighting is important to achieve a healthy environment upbringing for children in general and for people with special needs as well.

This study explores the impact of landscape design, which has gained importance alongside architectural changes in shopping centers, and investigates preferences in the post-COVID-19 pandemic era. Although e-commerce has increased during the pandemic, research and societal behaviors suggest that shopping centers will continue to serve as contemporary agoras due to their socialization and leisure functions. However, in response to the pandemic, it is anticipated that newly designed shopping centers will be architecturally conceived as semi-outdoor or outdoor spaces, regardless of climate conditions. This transformation will involve the softening of rigid appearances through landscape elements, making them both ecologically and psychologically sustainable. The number of studies on this subject is limited. To address this knowledge gap, an online survey was conducted with 586 randomly selected users across nine shopping centers located in three major cities of Turkey: Istanbul, Ankara, and Izmir, with three shopping centers in each city. The survey investigated users' preferences for architectural styles (indoor, semi-outdoor, or outdoor) and landscape design in shopping centers. The findings of the study indicate that post-pandemic, outdoor and semi-outdoor shopping centers are likely to be preferred more frequently. An emphasis is likely to be placed on natural landscape elements such as plants and water features in landscape design. Furthermore, shopping center designs are likely to become simpler, offering comfortable and spacious navigation areas while optimizing parking and transportation conditions. This study is expected to shed light on decision-making processes for future shopping centers. By incorporating consumer preferences, architects can enhance the sustainability of shopping center investments through next-generation design.

This study explores the impact of landscape design, which has gained importance alongside architectural changes in shopping centers, and investigates preferences in the post-COVID19 pandemic era. Although e-commerce has increased during the pandemic, research and societal behaviors suggest that shopping centers will continue to serve as contemporary agoras due to their socialization and leisure functions. However, in response to the pandemic, it is anticipated that newly designed shopping centers will be architecturally conceived as semi-outdoor or outdoor spaces, regardless of climate conditions. This transformation will involve the softening of rigid appearances through landscape elements, making them both ecologically and psychologically sustainable. The number of studies on this subject is limited. To address this knowledge gap, an online survey was conducted with 586 randomly selected users across nine shopping centers located in three major cities of Turkey: Istanbul, Ankara, and Izmir, with three shopping centers in each city. The survey investigated users' preferences for architectural styles (indoor, semi-outdoor, or outdoor) and landscape design in shopping centers. The findings of the study indicate that postpandemic, outdoor and semi-outdoor shopping centers are likely to be preferred more frequently. An emphasis is likely to be placed on natural landscape elements such as plants and water features in landscape design. Furthermore, shopping center designs are likely to become simpler, offering comfortable and spacious navigation areas while optimizing parking and transportation conditions. This study is expected to shed light on decisionmaking processes for future shopping centers. By incorporating consumer preferences, architects can enhance the sustainability of shopping center investments through nextgeneration design. [ABSTRACT FROM AUTHOR]

Copyright of Geomatik is the property of Murat Yakar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the current global era, the development of technology and information is very rapid, so it is very easy to get information/news from the internet. Because of the ease of getting this information, there is a lot of circulating fake news (hoaxes), the news is not filtered so anyone can spread news that is not clear in content. This can lower a person's credibility in the professional world, cause division, threaten physical and mental health, and can also result in material losses. Based on this, to stop the spread of hoaxes is to detect them as early as possible and block them. This detection can use deep learning methods which are also one of the architectures of transformers, namely a combination of BERTopic which is used to find important words from the news narrative, then the words are combined into the narrative and classified using Indo Bidirectional Encoder Representation from Transformer (IndoBERT). For experiments, the author uses a dataset taken from the kaggle.com website entitled Indonesia False News (HOAX) dataset. This study uses a learning rate of 1e-5, a batch size of 16 and using 5 epochs so that the f1-Score results are 92% for validation data and 91% for testing data. [ABSTRACT FROM AUTHOR]

This research aims to determine the optimal dose of boiled mackerel tuna mixture on HI-PRO VITE 781 feed on gonadal maturity index and feed conversion ratio of transgenic mutiara catfish G4 in indoor hatchery maintenance at optimal temperature. This research was conducted at the Hatchery of the Faculty of Fisheries and Marine Sciences, Universitas Padjadjaran. The method used was an experimental method with a completely randomized design (CRD) method with four treatments, namely the difference in the dose of boiled mackerel tuna administration in comercial feed and three replications. The treatment in this study was the administration of boiled mackerel tuna doses of 3.5%, 2.5%, 1.5% in mixed feeds to G4 transgenic mutiara catfish and tested on non-transgenic mutiara catfish with a percentage of 3.5% female weight biomass and then added an 30 g HI-PRO-VITE 781 with two times feeding frequency. The research parameters included gonad maturity index and feed conversion ratio. The results showed that feeding a mixture of boiled mackerel tuna and HI-PRO-VITE 781 had a significant effect on the gonadal maturity index and feed conversion ratio. Feeding boiled mackerel tuna at 1.5% was the best treatment with a gonadal maturity index of 47.16% for females and 4.98% for males and a feed conversion value of 1.19 for 56 days of rearing. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Air Pollution & Health is the property of Tehran University of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper focuses on converting complex 3D maps created by LiDAR and SLAM technology into simple 2D maps to make them easier to understand. While 3D maps provide a lot of useful details for robots and computer programs, they can be difficult to read for humans who are used to flat maps. We developed a new system to clean up these 3D maps and convert them into intuitive and accurate 2D maps. The system uses three steps designed to correct different kinds of errors found in 3D LiDAR scan data: clustering-based denoising, height-based denoising, and Statistical Outlier Removal. In particular, height-based denoising is the method we propose in this paper, an algorithm that leaves only indoor structures such as walls. The paper proposes an algorithm that considers the entire range of the point cloud, rather than just the points near the ceiling, as is the case with existing methods, to make denoising more effective. This makes the final 2D map easy to understand and useful for building planning or emergency preparedness. Our main goal is to map the interior of buildings faster and more effectively, creating 2D drawings that reflect accurate and current information. We want to make it easier to use LiDAR and SLAM data in our daily work and increase productivity. [ABSTRACT FROM AUTHOR]

As the growth of society and the continuous upgrading of people's living standards increase, people's requirements for indoor environment are also increasing. To optimize the ventilation methods inside buildings, a numerical simulation method was used to construct numerical simulations of airflow organization and aerosol diffusion, and based on this model, better ventilation methods were determined. To optimize the determined better ventilation method, a multi-constraint optimization model was constructed using infection probability, thermal comfort, energy utilization coefficient, and velocity non-uniformity coefficient. The ventilation method was optimized through multi-objective constraints. To solve the optimization model, an optimized particle swarm algorithm was studied and designed. The results showed that under the "air rain" flow field, the maximum values of aerosol particles at the human body, bed surface, and outlet were 171, 769, and 19,973, respectively, while the minimum values were 4, 169, and 2197, respectively. The "air rain" flow field is a better ventilation method. The maximum and minimum values of the original non-uniformity coefficient were 0.44 and 0.08, respectively. After optimization by the particle swarm optimization algorithm, the maximum and minimum predicted non-uniformity coefficients were 0.457 and 0.08, respectively. The original value and predicted value are very close. The numerical model and algorithm constructed by the research institute are effective. The algorithm designed by the research institute can provide technical support for multi-objective optimization of indoor ventilation methods. [ABSTRACT FROM AUTHOR]

Strawberries (Fragaria ×ananassa) are being produced increasingly in indoor vertical farms, where the light quality of sole-source lighting is a primary factor that influences the outcomes of crop production. Far-red (FR) light (700-750 nm) has been shown to promote plant responses such as leaf expansion, biomass accumulation, and flowering in some long-day plant species. However, the impacts of including FR light in sole-source lighting on strawberries have not been fully understood. This study investigated the impacts of FR light on the growth and development of long-day strawberries 'Albion' and 'Monterey' in an indoor vertical farm. We hypothesized that the addition of FR light under a long photoperiod would promote leaf expansion, biomass accumulation, flowering, and fruit production in long-day strawberries. Bareroot strawberry plants were grown in a deep-water-culture hydroponic system at an air temperature of 22 °C and an 18-hour photoperiod using 90 lmol.m-2.s-1 of blue (peak 5 455 nm) + 250 lmol.m-2.s-1 of red (peak 5 660 nm) light-emitting diodes (LEDs) with or without adding 50 lmol.m-2.s-1 of FR (peak 5 730 nm) LEDs. After 5 weeks of lighting treatments, additional FR light increased the leaf area and shoot dry mass of strawberry 'Monterey' by 74% and 73%, respectively, and the number of crowns per plant of strawberry 'Albion' by 33%. However, FR light did not influence flowering time in either cultivar. Adding FR light increased the number of fruit harvested per plant by 36%, the total fruit yield by 48%, and the total soluble solids of fruit by 12% in strawberry 'Albion', but not in 'Monterey'. In both cultivars, FR light did not affect the individual fruit mass. Our results suggest that the addition of FR light in sole-source lighting can promote leaf expansion, biomass accumulation, fruit yield, and fruit quality in at least some long-day strawberry cultivars. [ABSTRACT FROM AUTHOR]

In healthcare settings, controlling airborne contaminants is crucial for ensuring the safety of healthcare workers and patients, especially in isolation rooms designed with negative pressure systems. This paper, a novel experimental study of the distribution of airborne contamination within an Airborne Infection Isolation Room (AIIR) using tracer gas, identifies patients in Iraq to reduce the pollution and infection disease from a patient with COVID-19 or any other Respiratory patient disease by using a negative pressure room Terms of condition at three different Air Change (ACH) 6, 9 and 12 ACH. Concentrations of airborne contaminants in the breathing zone of surgical staff are measured, along with analyses of velocity, temperature, and humidity distribution in the patient's thermal plume. Negative pressure shows acceptable temperature and velocity variations according to the World Health Organization. Higher ACH and AC inlet velocities lead to decreased relative humidity and enhance heat removal efficiency, and air exchange efficiency. Contaminant removal, evaluated through the Contaminant Removal Effectiveness (CRE), exhibits superiority under high Air Conditioner AC inlet modes and increased ACH rates, recording values of 1.1 and 1.2. The study strongly recommends isolation rooms for respiratory patients in negative-pressure ventilated operating rooms to mitigate infection transmission risks to the surgical staff. [ABSTRACT FROM AUTHOR]

This study investigates the potential of Cesium−formamidinium-based (CsyFA1−yPb(IxBr1−x)3) perovskite materials as promising candidates for efficient and stable perovskite solar cells (PSCs), that can be tailored for indoor applications. These materials offer the unique advantage of simultaneously stabilizing photoactive compositional phase transitions and enhancing thermal stability, making them well-suited for indoor environments. The optical band gaps of Cesium−formamidinium, ranging from 1.5 to 1.8 eV, can be engineered to align with the spectrum of light sources commonly used indoors. Therefore, this study directs into the design and simulation of Cesium-Formamidinium-Based PSCs, with a specific emphasis on optimizing their performance under indoor LED illumination. Parameter manipulation related to the Hole Transport Layer (HTL) and Electron Transport Layer (ETL) is utilized to establish optimal band alignment in order to reduce recombination losses and boost power conversion efficiency. A co-design approach between the ETL and HTL is introduced, enabling precise engineering of interfaces, and optimizing charge transport and collection efficiency. This research presents an optimal design with a conduction band minimum (VBM) energy level of 4.05 eV for the ETL and a valence band maximum (VBM) energy level of 5.15 eV for the HTL, resulting in a power conversion efficiency (PCE) of 25.00%, and an open-circuit voltage (Voc) of 0.939 V. [ABSTRACT FROM AUTHOR]

Urban science plays a pivotal role in understanding the complex interactions between fireworks, air quality, and urban environments. Dense firework smoke worsens air quality and poses a health hazard to the public. In this study, we show a situation where extremely foggy meteorological conditions coincided with intense anthropogenic emissions, including fireworks, in an urban area. For the first time, the chemical composition and sources of non-refractory submicron aerosol (NR-PM1) in outdoor and indoor air were characterized in Vilnius (Lithuania) using an aerosol chemical speciation monitor (ACSM) and Positive Matrix Factorization for the period before the fireworks, on New Year's Eve, and after the fireworks in 2020/2021; thus, typical changes were assessed. Due to stagnant weather conditions and increased traffic, the highest concentrations of black carbon (BC) (13.8 μg/m3) were observed before the fireworks display. The contribution of organic (Org) fraction to the total NR-PM1 mass concentration, in the comparison of the values of a typical night and New Year's Eve (from 9 p.m. to 6 a.m.), increased from 43% to 70% and from 47% to 60% in outdoor and indoor air, respectively. Biomass-burning organic aerosol (BBOA, 48% (44%)) and hydrocarbon-like organic aerosol (HOA, 35% (21%)) dominated the organic fraction indoors and outdoors, respectively. HOA was likely linked to increased traffic during the event, while BBOA may have been related to domestic heating and fireworks. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are a class of hydrocarbons, some of which are established human carcinogens. Human exposure to these chemicals is complex and originates from both indoor and outdoor sources. This study measured the concentration of PAHs in the gaseous and particulate phases during the cold months of 2022 using XAD-2 sorbent tubes and Polytetrafluoroethylene (PTFE) filters in the indoor air of coffee shops in Zahedan, Iran (n = 23). The average concentrations of particulate-bound PAHs and gaseous PAHs were 13,411.86 ± 6517.24 ng/m³ and 6432.76 ± 4311.72 ng/m³, respectively. Source apportionment analyses indicated that the primary sources of PAHs in coffee shops were fossil fuel combustion and environmental tobacco smoke (ETS), commonly referred to as second and third-hand smoke. The lifetime cancer risk (LTCR) of inhaled PAHs was calculated using the Monte Carlo simulation method. The mean LTCR for adults and children from inhaling these substances were 9.43 × 10-6 ± 5.06 × 10-6 and 5.34 × 10-6 ± 2.87 × 10-6, respectively. The hazard quotient (HQ) of PAHs exceeded 1. These findings highlight the need to reduce PAHs exposure in public spaces through proper health warning labels and regulated indoor smoking policies.

Introduction: This study aimed to investigate the concentration of Respirable Crystalline Silica (RCS) and respirable dust, Particulate matters (PM4 ) concentration in samples measured indoors and outdoors of the nine (9) selected households located proximal to gold mine tailings in Riverlea, Johannesburg. Materials and methods: Sampling locations were separated according to grids, based on distance from the tailings; A (500m

The majority of current commercial available Unmanned Aerial Vehicles (UAV) depend mainly on satellite signals to estimate their position. Although this is not a problem in outdoor environments, in scenarios where these signals are obstructed, the UAV may be unable to estimate its position, rendering navigation infeasible. Thus, in satellite-less environments alternative methods are required. The AutoNAV package allows the simulation of Unmanned Aerial Vehicles (UAVs) in environments with limited-to-no satellite signal (such as indoor environments), taking advantage of (terrestrial) radio measurements between stationary reference points (anchors) and a UAV to estimate the position of the UAV. The package provides Python implementations of two algorithms for this purpose: Generalized Trust Region Sub-Problem (GTRS) and Weighted Least Squares (WLS). To provide a user-friendly experience and a straightforward comparison process for other researchers, functions that extract the most relevant metrics and plot the ground truth trajectory and the estimated positions by the algorithms are also included. In the provided examples, a scenario of UAV navigation inside a warehouse, e.g., for stock inventory counting, is designed and depicted. Moreover, the package is designed with modularity in mind, enabling researchers to easily implement, compare and integrate their work, fostering a centralized and straightforward approach for analyzing the performance of existing methods.

Background Problems: Nutrition is an important factor in improving athlete performance, but many athletes still experience problems such as ignorance about the right portion and type of food, unbalanced energy intake, and a lack of knowledge about the nutrients the body needs. Research Objectives: This study aims to evaluate the nutritional intake of hockey student-athletes who are members of indoor hockey clubs in Tangerang City. Methods: This study used a quantitative descriptive method with a survey approach. Data were collected using a single and 24-hour reported food recall, and as many as 24 research subjects were involved in this study, there are student-athletes in the club’s indoor hockey in Tangerang City. Data analysis used a statistical approach in the form of percentages. The nutritional analysis in this study focused more on the percentages of carbohydrate, protein, fat, and caloric intake eaten by athletes within a 24-hour period. Findings and Results: This study showed the average results of the nutrition intakes include 83% for protein, 53% for carbohydrates, 72% for fat, and 52% for calories. The results show that the knowledge of indoor hockey athletes was still lacking. Conclusion: The findings of this study indicate that the nutritional intake of indoor hockey athletes in Tangerang City is still far from optimal. It is vital for athletes to enhance their understanding of proper nutrition and energy needs, as this can significantly impact their fitness levels and performance outcomes. Coaches and trainers should prioritise nutrition education as part of regular training programs, collaborating with nutritionists to ensure that athletes receive the necessary guidance on their dietary habits. In the future, developing integrated nutritional programs tailored to the specific needs of indoor hockey athletes will be crucial. This research contributes to a growing understanding of the importance of nutrition in sports and underscores the need for continued efforts to address the dietary challenges faced by student athletes.

Background: In developing countries, including China, solid-fuel-based heating and cooking is common. For older people, the multimorbidity prevalence is exceptionally high. Nevertheless, studies on the associations of indoor solid fuels use, especially switching fuels types, on multimorbidity in middle-aged and older people is scarce. Methods: Data from five waves of the China Health and Retirement Longitudinal Study were used in this study. Indoor fuels were classified as solid or clean fuels. Physical-psychological-cognitive multimorbidity (PPC-multimorbidity) was defined as the simultaneous presence of three disease types (physical illness, psychological disorders, cognitive impairment). Using Cox proportional risk models, hazard ratios (HRs) and 95 % confidence intervals (95 % CI) were calculated to investigate the associations of heating- and cooking-related baseline indoor fuels and switching indoor fuels with PPC-multimorbidity incidence. Results: In the heating (n=3121, mean age=56.55 years, male proportion=54.25 %) and cooking (n=3574, mean age=56.67 years, male proportion=52.94 %) analyses, 75.07 % and 45.64 % of the participants used solid fuels at baseline, and 564 (18.07 %) and 613 (17.15 %) PPC-multimorbidity cases were diagnosed during follow-up, respectively. Participants with baseline heating- and cooking-based solid fuels use had greater PPC-multimorbidity incidences [HRs (95 % CIs): 1.23 (0.98, 1.55) and 1.44 (1.21, 1.73)], respectively. Additionally, combined baseline heating- and cooking-based solid fuels use was associated with even greater PPC-multimorbidity incidence [HR (95 % CI): 1.55 (1.18, 2.04)]. Persistent solid fuels use obviously increased the PPC-multimorbidity incidence [HRs (95 % CIs): 2.43 (1.67, 3.55) for heating and 2.63 (2.03, 3.40) for cooking]. Moreover, switching from solid to clean fuels was associated with a significantly decreased PPC-multimorbidity incidence [HRs (95 % CIs): 0.27 (0.20, 0.35) for heating and 0.36 (0.28, 0.46) for cooking]. Conclusions: Long-term solid-fuels use is associated with an increased PPC-multimorbidity incidence, and switching to cleaner fuels is associated with a decreased PPC-multimorbidity incidence in adults aged ≥45 years.

BackgroundCooking is a substantial contributor to air pollutant exposures in many residences. Effective use of kitchen ventilation can mitigate exposure; however, information on its availability, usage, and potential to increase its use across the population has been limited.ObjectiveThis study aimed to obtain nationally representative information on cooking methods, kitchen ventilation availability and usage, and the potential for education to increase effective usage.MethodsAn online survey was sent to a representative sample of Canadian homes to collect data on cooking methods, the presence and use of mechanical kitchen ventilation devices, perceived device performance, and willingness to implement mitigation strategies. Responses were weighted to match key demographic factors and analyzed using non-parametric statistics.ResultsAmong the 4500 respondents, 90% had mechanical ventilation devices over the cooktop (66% of which were vented to the outside), and 30% reported regularly using their devices. Devices were used most often for deep-frying, followed by stir-frying, sautéing or pan-frying, indoor grilling, boiling or steaming. Almost half reported rarely or never using their ventilation devices during baking or oven self-cleaning. Only 10% were fully satisfied with their devices. More frequent use was associated with the device being vented to the outdoors, having more than two speed settings, quiet operation if only one speed, covering over half of the cooktop, and higher perceived effectiveness. After being informed of the benefits of kitchen ventilation, 64% indicated they would consider using their devices more often, preferentially using back burners with ventilation, and/or using higher ventilation device settings when needed.ImpactThis study provides population-representative data on the most used cooking methods, kitchen ventilation availability and usage, and influencing factors in Canadian homes. Such data are needed for exposure assessments and evaluating the potential to mitigate cooking-related pollutant exposures via more effective use of kitchen ventilation. The data can be reasonably extrapolated to the United States, given the similarities in residential construction practices and cultural norms between the two countries.

BackgroundSeveral studies suggest that far-field transmission (>6 ft) explains a significant number of COVID-19 superspreading outbreaks.ObjectiveTherefore, quantifying the ratio of near- and far-field exposure to emissions from a source is key to better understanding human-to-human airborne infectious disease transmission and associated risks.MethodsIn this study, we used an environmentally-controlled chamber to measure volatile organic compounds (VOCs) released from a healthy participant who consumed breath mints, which contained unique tracer compounds. Tracer measurements were made at 0.76 m (2.5 ft), 1.52 m (5 ft), 2.28 m (7.5 ft) from the participant, as well as in the exhaust plenum of the chamber.ResultsWe observed that 0.76 m (2.5 ft) trials had ~36-44% higher concentrations than other distances during the first 20 minutes of experiments, highlighting the importance of the near-field exposure relative to the far-field before virus-laden respiratory aerosol plumes are continuously mixed into the far-field. However, for the conditions studied, the concentrations of human-sourced tracers after 20 minutes and approaching the end of the 60-minute trials at 0.76 m, 1.52 m, and 2.28 m were only ~18%, ~11%, and ~7.5% higher than volume-averaged concentrations, respectively.SignificanceThis study suggests that for rooms with similar airflow parameters disease transmission risk is dominated by near-field exposures for shorter event durations (e.g., initial 20-25-minutes of event) whereas far-field exposures are critical throughout the entire event and are increasingly more important for longer event durations.Impact statementWe offer a novel methodology for studying the fate and transport of airborne bioaerosols in indoor spaces using VOCs as unique proxies for bioaerosols. We provide evidence that real-time measurement of VOCs can be applied in settings with human subjects to estimate the concentration of bioaerosol at different distances from the emitter. We also improve upon the conventional assumption that a well-mixed room exhibits instantaneous and perfect mixing by addressing spatial distances and mixing over time. We quantitatively assessed the exposure levels to breath tracers at alternate distances and provided more insights into the changes on "near-field to far-field" ratios over time. This method can be used in future to estimate the benefits of alternate environmental conditions and occupant behaviors.