Workplace personal exposure to respirable PM fraction: a study in sixteen indoor environments

AbstractThe present paper focuses on respirable particulate matter (RPM) measurements conducted at the breathing zone of adult volunteers in sixteen different working environments: two offices, a house, a chemical laboratory, a non–smoking shop, a pharmacy store, a car garage, a hairdresser's store, a photocopy store, a taxi, a gym, a mall, a restaurant, a bar, a kiosk and a school. The sixteen different cases were categorized according to the location, the type of the activities taking place indoors, the number of occupants, the proximity to heavy traffic roads, the ventilation pattern etc. According to the results, the maximum particle concentration (in average 285μg m−3) was recorded at the hairdresser store while the minimum concentration was measured in the cases of the housewife and the employee in the non–smoking shop (in average 30μg m−3). The results indicated smoking as a factor which strongly influences the exposure levels of both smokers and passive smokers. Furthermore, it was found that the building ventilation pattern comprises an important factor influencing the exposure levels especially in cases of buildings with great number of visitors (resuspension) and smoking

Concentrations of VOCs and ozone in indoor environments: A case study in two Mediterranean cities during winter period

Building materials represent the largest surfaces indoors and are the major contributors of volatile organic compounds (VOCs) in the indoor environment. This study which is conducted in the frame of BUMA project (Prioritization of Building Materials Emissions), aims at assessing the human exposure to air hazards emitted by building materials. In this study, indoor and outdoor VOCs and ozone measurements from field campaigns in two Mediterranean cities (Nicosia and Athens in winter period) are presented and discussed. The field campaigns concern weekly measurements. The campaigns were conducted in four buildings in each city (1 Public building, 1 school and 2 houses) and concern weekly measurements. Passive samplers were used for collecting VOCs and ozone. Eight (8) hydrocarbons (benzene, toluene, ethylbenzene, m,p-xylene, a-pinene, o-xylene and d-limonene), five (5) carbonyl compounds (formaldehyde, acetaldehyde, proprionaldehyde, acetone and hexanaldehyde) and ozone have been measured. Additional air exchange measurements have been conducted using tracer gas techniques. Hazardous substances such as benzene, formaldehyde and acetaldehyde present indoor concentrations that range between 1.5-10.2, 5.8-43.2 and 4.5-15 μg/m3, respectively. VOC concentration data show a considerable variability due to the different indoor emission sources, ventilation rates and outdoor environment's influence. A significant contribution to indoor measured concentrations seems to come from the building materials. Ozone outdoor concentrations are reduced substantially inside, indicating relatively strong indoor ozone sinks

The past, present and future of indoor air chemistry

This is the peer reviewed version of the following article: Bekö, G. et al. (2020). The past, present and future of indoor air chemistry. Indoor Air, 30(3), 373-376. , which has been published in final form at https://doi.org/10.1111/ina.12634. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.This is an editorial contribution to the Journal Indoor Air on the future direction of indoor air chemistry research

User-Centred Design of a Final Results Report for Participants in Multi-Sensor Personal Air Pollution Exposure Monitoring Campaigns

Using low-cost portable air quality (AQ) monitoring devices is a growing trend in personal exposure studies, enabling a higher spatio-temporal resolution and identifying acute exposure to high concentrations. Comprehension of the results by participants is not guaranteed in exposure studies. However, information on personal exposure is multiplex, which calls for participant involvement in information design to maximise communication output and comprehension. This study describes and proposes a model of a user-centred design (UCD) approach for preparing a final report for participants involved in a multi-sensor personal exposure monitoring study performed in seven cities within the EU Horizon 2020 ICARUS project. Using a combination of human-centred design (HCD), human-information interaction (HII) and design thinking approaches, we iteratively included participants in the framing and design of the final report. User needs were mapped using a survey (n = 82), and feedback on the draft report was obtained from a focus group (n = 5). User requirements were assessed and validated using a post-campaign survey (n = 31). The UCD research was conducted amongst participants in Ljubljana, Slovenia, and the results report was distributed among the participating cities across Europe. The feedback made it clear that the final report was well-received and helped participants better understand the influence of individual behaviours on personal exposure to air pollution

Harmonization and Visualization of Data from a Transnational Multi-Sensor Personal Exposure Campaign

Use of a multi-sensor approach can provide citizens with holistic insights into the air quality of their immediate surroundings and their personal exposure to urban stressors. Our work, as part of the ICARUS H2020 project, which included over 600 participants from seven European cities, discusses the data fusion and harmonization of a diverse set of multi-sensor data streams to provide a comprehensive and understandable report for participants. Harmonizing the data streams identified issues with the sensor devices and protocols, such as non-uniform timestamps, data gaps, difficult data retrieval from commercial devices, and coarse activity data logging. Our process of data fusion and harmonization allowed us to automate visualizations and reports, and consequently provide each participant with a detailed individualized report. Results showed that a key solution was to streamline the code and speed up the process, which necessitated certain compromises in visualizing the data. A thought-out process of data fusion and harmonization of a diverse set of multi-sensor data streams considerably improved the quality and quantity of distilled data that a research participant received. Though automation considerably accelerated the production of the reports, manual and structured double checks are strongly recommended

Results of the first European Source Apportionment intercomparison for Receptor and Chemical Transport Models

In this study, the performance of the source apportionment model applications were evaluated by comparing the model results provided by 44 participants adopting a methodology based on performance indicators: z-scores and RMSEu, with pre-established acceptability criteria. Involving models based on completely different and independent input data, such as receptor models (RMs) and chemical transport models (CTMs), provided a unique opportunity to cross-validate them. In addition, comparing the modelled source chemical profiles, with those measured directly at the source contributed to corroborate the chemical profile of the tested model results. The most used RM was EPA- PMF5. RMs showed very good performance for the overall dataset (91% of z-scores accepted) and more difficulties are observed with SCE time series (72% of RMSEu accepted). Industry resulted the most problematic source for RMs due to the high variability among participants. Also the results obtained with CTMs were quite comparable to their ensemble reference using all models for the overall average (>92% of successful z-scores) while the comparability of the time series is more problematic (between 58% and 77% of the candidates’ RMSEu are accepted). In the CTM models a gap was observed between the sum of source contributions and the gravimetric PM10 mass likely due to PM underestimation in the base case. Interestingly, when only the tagged species CTM results were used in the reference, the differences between the two CTM approaches (brute force and tagged species) were evident. In this case the percentage of candidates passing the z-score and RMSEu tests were only 50% and 86%, respectively. CTMs showed good comparability with RMs for the overall dataset (83% of the z-scores accepted), more differences were observed when dealing with the time series of the single source categories. In this case the share of successful RMSEu was in the range 25% - 34%.JRC.C.5-Air and Climat

Particulate matter source apportionment in indoor air

Several studies underline the role of good indoor air quality since an average person spends more than 80% of the day in an indoor environment. Particulate matter (PM) is a major pollutant and their connection with adverse health effects attracts the scientific interest. The present study aimed at identifying the sources (or the groups of sources) of particulate matter (PM) and estimating their contribution to measured concentrations in an indoor environment. For the purpose of the study measurements of particles size distribution in the size range of 0.23-20μm were conducted in a real-scale chamber room (volume 18m³). A data base with the profiles of 25 indoor sources as well as the emission and deposition rates was created. Additionally measurements of particles mass and number concentration in the same size range were conducted in real indoor environments offices and a house. Afterwards a receptor model (Positive Matrix Factorization) was applied on the experimental data for the source apportionment study in a working and a residential environment. Furthermore the sensitivity of several parameters on the model output was examined.Ο σύγχρονος τρόπος ζωής έχει οδηγήσει τον άνθρωπο στην κατανάλωση περισσοτέρου από το 80% του χρόνου του σε εσωτερικούς χώρους. Ένας από τους πιο σημαντικούς ρύπους είναι τα αιωρούμενα σωματίδια και η σύνδεση της ανθρώπινης έκθεσης σε αυτά με επιπτώσεις στην υγεία απασχολεί ιδιαίτερα την επιστημονική κοινότητα. Ο στόχος της παρούσας διατριβής είναι η ανίχνευση πηγών ή ομάδων πηγών αιωρούμενων σωματιδίων (particulate matter ΡΜ) και η εκτίμηση των συνεισφορών τους στις συγκεντρώσεις στον αέρα εσωτερικών χώρων. Για το σκοπό αυτό πραγματοποιήθηκαν μετρήσεις κατανομής μεγέθους σωματιδίων (στο εύρος διαμέτρου 0.23-20μm) σε απομονωμένο περιβάλλον (θάλαμος δοκίμων όγκου 18m³) και δημιουργήθηκε μια βάση δεδομένων με τα προφίλ 25 πηγών σωματιδίων σε εσωτερικούς χώρους. Επίσης εξετάστηκαν ο ρυθμός εκπομπής και ο ρυθμός εναπόθεσης των σωματιδίων για κάθε πηγή. Παράλληλα πραγματοποιήθηκαν μετρήσεις συγκέντρωσης (αριθμού και μάζας) σωματιδίων και κατανομής τους στο ίδιο φάσμα μεγέθους σε πραγματικούς χώρους γραφείων και κατοικίας. Στα αποτελέσματα των μετρήσεων εφαρμόστηκε μοντέλο αποδέκτη (receptor model) με την μέθοδο Positive Matrix Factorization με σκοπό την εκτίμηση των συνεισφορών των πηγών σωματιδίων στις παρατηρούμενες συγκεντρώσεις των τελευταίων σε πραγματικούς χώρους γραφείων και κατοικίας. Παράλληλα εξετάστηκαν οι παράγοντες που βελτιστοποιούν το αποτέλεσμα της εφαρμογής του μοντέλου

Vehicle-induced fugitive particulate matter emissions in a city of arid desert climate

This study investigates and proposes emission factors (EFs) and models for vehicle-induced exhaust (VEX) and fugitive (VfPM) particulate matter emissions representative of areas with arid climates. Particle number (PNC) and mass (PMC) concentrations and their integrated samples were collected for a period of three months for both PM10 and PM2.5 next to a trafficked road in the city of Doha, Qatar. Using Positive Matrix Factorization (PMF) on the elemental data of the samples, six distinct PM sources were identified: traffic exhaust, dust resuspension, fresh and aged sea salt, secondary aerosols, and fuel oil/shipping. Dispersion modelling and regression analysis were combined to derive EFs (linear analysis) and models (non-linear analysis) for the total traffic fleet (heavy and light duty). The estimated EFs were between 620 and 730 mg VKT−1 (VKT; Vehicle Kilometer Travelled) (adj. R2 ~ 0.84) and between 1080 and 1410 mg VKT−1 (adj. R2 ~ 0.70) for VEX and VfPM, respectively. The integration of field measurements, chemical characterization, and dispersion modelling presented herein is one of the first similar studies conducted in the wider region, identifies the importance of fugitive PM (fPM), and marks the need for further studies to improve emissions modelling of VfPM in arid desert climates