Indoor Workplaces Research Articles

Investigation of perceived annoyance in indoor workplaces using short and ultra-short sound samples

Typically, metrics crucial for assessing sound quality are derived from high-quality audio samples obtained in controlled environments. However, due to the sensitive nature of workplace settings, recording audio samples on-site becomes impractical. Privacy emerges as a significant concern for all when collecting audio samples. Consequently, best practice would require that all analyses must occur either locally on a device used to record audio or in the cloud, utilizing a purely mathematical approach. The paper aims to formulate methodologies for determining psycho-acoustic sound quality metrics without the need to analyze audio data directly. This can be achieved by collecting and analyzing data in small batches. The variation of these metrics over these smaller samples can serve as an indicator of sound quality. Initiating the determination of values for psycho-acoustic sound quality metrics such as loudness (N), sharpness (S), roughness (R) and fluctuation strength (FS) in short and ultra-short batches, followed by monitoring their variation over an extended period (e.g., 5 minutes), provides additional insight into the sound characteristics of the space. Using the obtained psycho-acoustic sound quality metrics, we will explore the perceived annoyance among occupants through indoor soundscape assessments.

Expansion of Smoke-Free Laws in Public Places and Support for Smoke-Free in Malaysia: Findings from the 2020 ITC Malaysia Survey.

Smoke-free laws (SFL) are more effective with public support. This study investigated the smoking prevalence, public perceptions of smoking rules, and support for comprehensive SFL among 1047 people who smoke (PWS) and 206 people who do not smoke (PNS) aged ≥18 in the 2020 International Tobacco Control Malaysia Survey. Smoking prevalence was highest in nighttime entertainment venues (85.7%), non-air-conditioned eateries (49.7%), and indoor workplaces (34.6%). Respondents reported that smoking was banned in most indoor workplaces (81.7% PNS, 69.2% PWS), air-conditioned eateries (84.7% PNS, 75.7% PWS), and non-air-conditioned eateries (81.2% PNS, 78.7% PWS), but much less so in nighttime entertainment venues (30.1% PNS, 24.6% PWS). Support for comprehensive SFL in public venues was highest among PNS (≥84.9%) but still substantial among PWS (≥49.9%). PWS under 40, Malay, married, and aware of smoking rules supported SFL more. Robust SFL enforcement is essential in Malaysia to reduce secondhand smoke exposure in public places.

Adaptation of indoor ornamental plants to various lighting levels in growth chambers simulating workplace environments

Despite the growing interest in indoor greenery and its positive effects on occupants’ well-being, there is limited knowledge on the optimal light levels for indoor plants that ensure energy efficiency and sustainable growth. This study explored the survival of ornamental plants under low-light conditions typical of indoor workplaces without daylight and investigated the impact of increased light intensity or extended day length on their growth. Three species of foliage plants (Epipremnum aureum, Pachira aquatica, and Rhaphidophora tetrasperma) were cultivated in growth chambers with three different lighting schemes. The results showed that plants sustained growth with 6.8 μmol m−2 s−1 white LED light for 9 h/day, suggesting that extra lighting might not be necessary for shade-tolerant species in offices. In this environment, plants maintained efficient photosynthesis under low illumination by increasing their specific leaf area. Elevating the light to 20.1 μmol m−2 s−1 and extending the day length to 18 h/day enhanced the plants’ relative growth rate. Climbing plants allocated more biomass to stems, resulting in a lower leaf weight ratio and noticeably altering their appearance. This study demonstrates that customized lighting strategies effectively support indoor greening goals, like adjusting intensity for energy savings or adding light for greening large spaces.

Assessment of radon levels in indoor workplaces in Tunisia and associated radiological risks

ABSTRACT This study aimed to assess indoor radon levels within different workplaces in Tunisia, including universities, schools, spa centres, and phosphate fertiliser factories. A total of 110 locations within these workplaces were monitored using solid-state nuclear track detectors (LR 115). The obtained results indicated that the geometric mean (GM) values of indoor radon concentrations measured at these locations were 24.6 Bq m−3 for universities, 31.3 Bq m−3 for schools, 72.2 Bq m−3 for spa centres, and 70.0 Bq m−3 for phosphate fertiliser factories. Overall, the GM of indoor radon concentrations measured in the four studied workplaces remained below standard values. Statistical analysis using the two-sample Student t-test revealed significant differences between the workplaces. The calculated annual effective doses due to radon inhalation were found to have GM values of 0.2 mSv y−1 for universities, 0.2 mSv y−1 for schools, 0.5 mSv y−1 for spa centres, and 0.4 mSv y−1 for phosphate fertiliser factories. These values are comparable to worldwide average values. Other risk parameters, such as lung cancer risk and lung cancer cases were also determined and reported in this study. While this study did not investigate the factors influencing radon concentrations, its primary advantage lies in being the first comparative study monitoring various workplaces in Tunisia, covering both underground and above-ground settings.

Eco-Friendly Sanitization of Indoor Environments: Effectiveness of Thyme Essential Oil in Controlling Bioaerosol Levels and Disinfecting Surfaces.

Bioaerosols and pathogens in indoor workplaces and residential environments are the primary culprits of several infections. Techniques for sanitizing air and surfaces typically involve the use of UV rays or chemical sanitizers, which may release chemical residues harmful to human health. Essential oils, natural substances derived from plants, which exhibit broad antimicrobial properties, could be a viable alternative for air and surface sanitation. The objective of this study has been to investigate the efficacy of thyme essential oil (TEO) in environmental sanitation processes. In Vitro assays through agar well diffusion, disk volatilization and tube dilution methods revealed significant antimicrobial activity of TEO 100% against foodborne and environmental isolates, with both bacteriostatic/fungistatic and bactericidal/fungicidal effects. Therefore, aqueous solutions of TEO 2.5% and 5% were formulated for air sanitation through nebulization and surface disinfection via direct contact. Bioaerosol samples and surface swabs were analyzed before and after sanitation, demonstrating the efficacy of aqueous solutions of TEO in reducing mesophilic and psychrophilic bacteria and environmental fungi levels in both air and on surfaces. The obtained results prove the antimicrobial potential of aqueous solutions of TEO in improving indoor air quality and surface cleanliness, suggesting thyme essential oil as an effective and safe natural sanitizer with minimal environmental impact compared to dangerous chemical disinfectants.

Microplastics suspended in dust from different indoor environments in Barranquilla, Colombia: Predominant microparticles?

Considering that microplastics (MPs) are classified as ubiquitous pollutants, that air quality affects human health, and that people remain indoors most of the time, the need has arisen to evaluate the exposure to MPs within the suspended dust in indoor environments. With this objective, the present study carried out passive sampling to analyze the precipitation of microparticles in some indoor residential environments (2 apartments) and workplaces (an office, a pastry shop, a gift shop, and a paint shop) in Barranquilla, Colombia. The quantification and physical characterization of microparticles were carried out under a stereomicroscope, and the chemical characterization was carried out by infrared microspectroscopy (μFTIR). The highest average concentration of MPs in the apartments was found in the air-conditioned rooms (1.1 × 104 MP/m2/day), and concerning the workplaces, the gift shop and the paint shop were the spaces with a higher proportion of MPs (6.0–6.1 × 103 MP/m2/day), with polyesters being the main synthetic polymers, but being semi-synthetic particles the predominant among the samples. Regarding its morphology, fibers were the most abundant shape (>90%), grouping mainly in the 1000–5000 μm range, while the few fragments found were mostly grouped below 50 μm. Exposure by inhalation of MPs in adults was estimated between 1.7 × 102–1.6 × 103 MP/kg/day, while by ingestion it ranged between 2.7 × 102–2.4 × 103 MPs/kg/day. On the other hand, within our research, a significant presence of non-plastic microparticles was found, which reached up to 69% in analyzed samples, corresponding mainly to cotton and cellulose, so we suggest that these should also be included in future studies that aim to estimate potential health implications from exposure to suspended micropollutants.

Effect of children secondhand smoke exposure associated with GABA concentration: Influence from parents who are extremely heavy smokers in urban households

BackgroundSecondhand smoke (SHS) poses the most considerable health risk to children in urban households. However, limited evidence exists regarding the impact of children exposure to SHS on gamma-aminobutyric acid (GABA) levels. This study aimed to investigate the level of cotinine and GABA and their association with variables related to children exposed to SHS. MethodsA cross-sectional analysis was conducted to assess urinary cotinine and GABA levels in respondents. The study involved 85 participants aged 2–4 years who resided with parents exhibiting heavy smoking habits in urban households in Bangkok, Thailand. Urinary cotinine and GABA concentrations were utilized as biomarkers and measured using an enzyme-linked immunosorbent assay kit. An independent t-test was employed to compare contributing factors with urinary cotinine metabolites. Spearman's correlation test was utilized to assess the relationship between cotinine metabolites and GABA concentration. ResultsThe study found a correlation between urinary cotinine metabolites and GABA concentration among children's (r = 0.260, p-value = 0.016), particularly influenced by parents exhibiting extreme heavy smoking in urban households. Male children exhibited significantly higher urinary cotinine metabolite concentrations than females (p-value = 0.040). Moreover, significantly elevated levels of cotinine metabolites (57.37 ± 10.27 ng/ml) were observed in households where parents engaged in extreme heavy smoking. ConclusionsThis research establishes a link between urinary cotinine metabolite levels and GABA concentration among children exposed to extreme heavy smoking by their parents in urban households. Consequently, smoking might impact neurobehavioral effects, potentially leading to insomnia. The study emphasizes the importance of promoting and safeguarding non-smokers from exposure to SHS in indoor workplaces, public spaces, and households, advocating for the implementation of smoke-free public health regulations.

Secondhand Smoke and Socio-Demographic Associated Factors: Results From the Vietnam Population-Based Provincial Global Adult Tobacco Survey in 2022.

Background: Secondhand smoke (SHS) has detrimental effects on community health, including coronary heart diseases, stroke, lung cancer etc. This manuscript exploited data from the Vietnam Population-based Provincial Global Adult Tobacco Survey (PGATS) in 2022 to update the prevalence of adult exposure to SHS and associated socio-demographic factors. Methods: With the sample size of 71,981 adults aged 15+ throughout 30 provinces and cities in Vietnam, data was collected using the Global Adult Tobacco Survey (GATS) questionnaire. Bivariate analysis and multivariate logistic regression modelling were performed. Results: In the past 30 days, 44.4% (95% CI: 44.0%-44.9%) adults aged 15+ exposed to SHS at home while 23.1% (95% CI: 22.6%-23.6%) exposed to SHS at work. Female exposure to SHS in the past 30 days was higher at homes but lower at indoor workplaces. Participants aged 15-24 were likely to have higher odds of SHS exposure in the past 30 days to other age groups. Those living in the urban areas had 1.15 times higher odds (95% CI: 1.08-1.22) of exposure to SHS than those in the rural areas. Current smokers tended to have 2.2 times higher odds of exposure to SHS at the indoor workplaces compared to non-smokers (95% CI: 2.05-2.37). Conclusions: The prevalence of exposure to SHS at home was still relatively high amongst the adult population. While there was a significant reduction of SHS exposure at indoor workplaces, there was a higher prevalence of women being exposed to SHS at home. The Government of Vietnam should continue to strictly implement the smoke-free environment resolution at indoor workplaces and appropriate communication campaigns to protect people, especially women from SHS exposure at homes.

Climate projections of human thermal comfort for indoor workplaces

Climate models predict meteorological variables for outdoor spaces. Nevertheless, most people work indoors and are affected by heat indoors. We present an approach to transfer climate projections from outdoors to climate projections of indoor air temperature (Ti) and thermal comfort based on a combination of indoor sensors, artificial neural networks (ANNs), and 22 regional climate projections. Human thermal comfort and Ti measured by indoor sensors at 90 different workplaces in the Upper Rhine Valley were used as training data for ANN models predicting indoor conditions as a function of outdoor weather. Workplace-specific climate projections were modeled for the time period 2070–2099 and compared to the historical period 1970–1999 using the same ANNs, but ERA5-Land reanalysis data as input. It is shown that heat stress indoors will increase in intensity, frequency, and duration at almost all investigated workplaces. The rate of increase depends on building and room properties, the workplace purpose, and the representative concentration pathway (RCP2.6, RCP4.5, or RCP8.5). The projected increase of the mean air temperature in the summer (JJA) outdoors, by + 1.6 to + 5.1 K for the different RCPs, is higher than the increase in Ti at all 90 workplaces, which experience on average an increase of + 0.8 to + 2.5 K. The overall frequency of heat stress is higher at most workplaces than outdoors for the historical and the future period. The projected hours of indoor heat stress will increase on average by + 379 h, + 654 h, and + 1209 h under RCP2.6, RCP4.5, and RCP8.5, respectively.

Public support for smoke-free private indoor and public outdoor areas in the Netherlands: A trend analysis from 2018-2022.

In addition to smoke-free policies in indoor public and workplaces, governments increasingly implement smoke-free policies at beaches, in parks, playgrounds and private cars ('novel smoke-free policies'). An important element in the implementation of such policies is public support. In the context of the ambition of the Netherlands to reach a smoke-free generation by 2040, we investigated temporal changes in public support for novel smoke-free policies. We analyzed annual cross-sectional questionnaires in a representative sample of the Dutch population from 2018 to 2022. Multivariable logistic regression was applied to model public support for each smoke-free policy area as a function of time (calendar year), smoking status, gender, and socioeconomic status. Interaction terms were added for time with smoking status and with socioeconomic status. A total of 5582 participant responses were included. Between 2018 and 2022, support increased most for smoke-free policies regarding train platforms (+16%), theme parks (+12%), beaches (+10%), and terraces (+10%). In 2022, average support was higher than 65% for all categories of smoke-free places and highest for private cars with children (91%). Regression analyses indicated significant increases in support over time within each category of smoke-free places (adjusted odds ratio, AOR between 1.09 and 1.17 per year), except smoke-free private cars with children (AOR=0.97; 95% CI: 0.89-1.05). Regardless of smoking status, support was high for places where children often go. Support for novel smoke-free places in the Netherlands is high and increasing, in particular for places frequented by children. This indicates the potential to implement such measures in the Netherlands.

Mismatched Refractive Index Strategy for Fabricating Laser-Driven Wood Diffusers from Bulk Wood for Illumination Applications.

Laser-diode-based solid-state lighting is primarily used in state-of-the-art illumination systems. However, these systems rely on light-converting inorganic phosphors, which have low quantum efficiencies and complex manufacturing conditions. In this study, a mismatched refractive index strategy is proposed to directly convert natural bulk wood into a laser-driven wood diffuser using a simple delignification and polymer infiltration method. The resulting material has the potential to be used in laser-driven diffuse illumination applications. The optical performance of the laser-driven wood diffuser is optimized by changing the density of natural wood. The optimal coefficient of illuminance variation of the wood diffuser is as low as 17.7%, which is significantly lower than that of commercial diffusers. The illuminance uniformity is larger than 0.9, which is significantly higher than the ISO requirements for indoor workplace lighting. The laser damage threshold is 7.9Jcm-2, which is considerably higher than those of the substrates of commercially available phosphors. Furthermore, the optimized wood diffuser exhibits outstanding mechanical properties, excellent thermal stability, tolerance to harsh environmental conditions, and low speckle contrast. These results show that the laser-driven wood diffuser is a promising laser-color converter that is suitable for indoor, long-distance outdoor, undersea, and other high-luminance laser lighting applications.

State of the literature discussing smoke-free policies globally: A narrative review.

Despite the success of the Framework Convention on Tobacco Control (FCTC), most jurisdictions in the world do not have policies that create 100% smoke-free environments in indoor workplaces, indoor public places, public transport, or other public places. We conducted a narrative review of articles that discuss smoke-free policies and describe the state of the current literature. A search of peer-reviewed and gray literature, published between 1 January 2004 and 30 April 2022, was conducted using PubMed and EMBASE databases. We classified articles based on the location of the policy discussed (WHO region, World Bank income classification) and the environment that was being made smoke-free. Insights related to policy development and implementation, as well as compliance and enforcement, were also identified. The search identified 4469 unique citations; 134 articles met the criteria for inclusion and underwent data extraction by two independent coders. The sample included articles published in or about jurisdictions in each WHO region, in high- and low- and mediumincome countries, and articles that discussed policies regulating smoke-free indoor workplaces, indoor public places, public transport, outdoor/quasi-outdoor environments, and other (unspecified) public places. Some important insights from the literature related to smoke-free policy implementation included tobacco industry interference, the important role of civil society, and the need for effective communication, education, and leadership. Enforcement officials' awareness and training, stakeholders' attitudes and beliefs, and understanding social norms were identified as relevant determinants of effective smoke-free policies. There continue to be challenges for implementing smoke-free policies in jurisdictions throughout the globe, in high- and low- and middle-income countries. The literature includes insights to support 100% smoke-free policies in each environment that must be made smoke-free as per the FCTC.

EFFECT OF WORKPLACE ERGONOMICS ENVIRONMENT ON HEALTH: A STUDY AMONG STUDENTS IN UUM

Ergonomics at the workplace is important in preventing workplace injuries and improve the work productivity. Consequently, promoting ergonomic workplace within the student’s context is relevant to addressed. This research aims to identify the relationship of workplace ergonomics environment on health among final year students. A survey was carried out among final year students at the School of Technology Management and Logistics (STML), UUM. This study using a questionnaire as the main instrument for data collection. A total of 168 STML final year students were answers the survey. The questionnaire addresses the student’s perception of ergonomic workplace experience (lighting, indoor air quality and workplace design) on student’s health. Data analysis was conducted using SPSS software. The research discovered that students suffered from low back pain and neck pain during and after study at the workplace. This study concludes that, improper workplace design has a negative effect on student’s health. Thus, this study contributes insight for ergonomic workplace from the student perspective.

The association between indoor workplace environment and heart rate variability in office workers of an information service company

The association between indoor workplace environment and heart rate variability in office workers of an information service company

Enrichment of human nasopharyngeal bacteriome with bacteria from dust after short-term exposure to indoor environment: a pilot study

BackgroundIndoor dust particles are an everyday source of human exposure to microorganisms and their inhalation may directly affect the microbiota of the respiratory tract. We aimed to characterize the changes in human nasopharyngeal bacteriome after short-term exposure to indoor (workplace) environments.MethodsIn this pilot study, nasopharyngeal swabs were taken from 22 participants in the morning and after 8 h of their presence at the workplace. At the same time points, indoor dust samples were collected from the participants’ households (16 from flats and 6 from houses) and workplaces (8 from a maternity hospital – NEO, 6 from a pediatric hospital – ENT, and 8 from a research center – RCX). 16S rRNA sequencing analysis was performed on these human and environmental matrices.ResultsStaphylococcus and Corynebacterium were the most abundant genera in both indoor dust and nasopharyngeal samples. The analysis indicated lower bacterial diversity in indoor dust samples from flats compared to houses, NEO, ENT, and RCX (p < 0.05). Participants working in the NEO had the highest nasopharyngeal bacterial diversity of all groups (p < 0.05). After 8 h of exposure to the workplace environment, enrichment of the nasopharynx with several new bacterial genera present in the indoor dust was observed in 76% of study participants; however, no significant changes were observed at the level of the nasopharyngeal bacterial diversity (p > 0.05, Shannon index). These “enriching” bacterial genera overlapped between the hospital workplaces – NEO and ENT but differed from those in the research center – RCX.ConclusionsThe results suggest that although the composition of nasopharyngeal bacteriome is relatively stable during the day. Short-term exposure to the indoor environment can result in the enrichment of the nasopharynx with bacterial DNA from indoor dust; the bacterial composition, however, varies by the indoor workplace environment.

Research on Safety Helmet Detection Algorithm Based on Improved YOLOv5s.

Safety helmets are essential in various indoor and outdoor workplaces, such as metallurgical high-temperature operations and high-rise building construction, to avoid injuries and ensure safety in production. However, manual supervision is costly and prone to lack of enforcement and interference from other human factors. Moreover, small target object detection frequently lacks precision. Improving safety helmets based on the helmet detection algorithm can address these issues and is a promising approach. In this study, we proposed a modified version of the YOLOv5s network, a lightweight deep learning-based object identification network model. The proposed model extends the YOLOv5s network model and enhances its performance by recalculating the prediction frames, utilizing the IoU metric for clustering, and modifying the anchor frames with the K-means++ method. The global attention mechanism (GAM) and the convolutional block attention module (CBAM) were added to the YOLOv5s network to improve its backbone and neck networks. By minimizing information feature loss and enhancing the representation of global interactions, these attention processes enhance deep learning neural networks' capacity for feature extraction. Furthermore, the CBAM is integrated into the CSP module to improve target feature extraction while minimizing computation for model operation. In order to significantly increase the efficiency and precision of the prediction box regression, the proposed model additionally makes use of the most recent SIoU (SCYLLA-IoU LOSS) as the bounding box loss function. Based on the improved YOLOv5s model, knowledge distillation technology is leveraged to realize the light weight of the network model, thereby reducing the computational workload of the model and improving the detection speed to meet the needs of real-time monitoring. The experimental results demonstrate that the proposed model outperforms the original YOLOv5s network model in terms of accuracy (Precision), recall rate (Recall), and mean average precision (mAP). The proposed model may more effectively identify helmet use in low-light situations and at a variety of distances.

Changes induced in the human respiratory tract by chronic cigarette smoking can reduce the dose to the lungs from exposure to radon progeny

Chronic cigarette smoking leads to changes in the respiratory tract that might affect the dose received from exposure to radon progeny. In this study, changes induced by cigarette smoking in the respiratory tract were collected from the literature and used for calculation of the dose received by the lungs and organs outside the respiratory tract. Morphological and physiological parameters affected by chronic smoking were implemented in the human respiratory tract model (HRTM) used by the International Commission of Radiological Protection (ICRP). Smokers were found to receive lung doses 3% smaller than the ICRP reference worker (non-smoking reference adult male) in mines and 14% smaller in indoor workplaces and tourist caves. A similar dose reduction was found for the extrathoracic region of the HRTM. Conversely, kidneys, brain, and bone marrow of smokers were found to receive from 2.3- up to 3-fold of the dose received by the respective organ in the ICRP reference worker, although they remained at least two orders of magnitude smaller than the lung dose. These results indicate that the differences in the lung dose from radon progeny exposure in cigarette smokers and non-smokers are smaller than 15%.

In the eye of the flourish wheel: an assessment of users’ health, well-being and productivity in university research rooms

ABSTRACT Indoor Environmental Quality (IEQ) is an immense concern for people’s wellness. The central argument in this research is that the IEQ in a university research room impacts users and their health, well-being and productivity. In addition, the present study relies on the Flourish Wheel to enhance the environment using the Biophilic Design approach, which in turn influences users’ satisfaction and work performance in five research rooms at Brunel University London. These rooms are situated in the same outdoor environment of a single university campus, but house multi-disciplinary occupants and vary in construction age, size, methods of ventilation and mode of thermostatic control. The current research paper firstly investigated the role of IEQ factors and sub-factors on occupants’ health, well-being, and productivity. Secondly, evaluated the possibility of improving the indoor workplace environment using Biophilic Design patterns. The most prominent finding is that the qualities of the five critical aspects of IEQ have significantly positive correlations with the occupants’ wellness. Another significant result is that the 14 Biophilic Design framework patterns can holistically offer different ways to improve the research rooms based on various environmental issues. The findings proposed in this study could be valuable both for design practitioners and academic researchers.

An optical flow-based method for condition-based maintenance and operational safety in autonomous cleaning robots

Autonomous professional cleaning robots are ubiquitous today, coexist with humans, and the demand continues to improve hygiene and productivity, especially in large indoor workplaces. Hence, a proper maintenance strategy is essential to monitor the robot’s health, assuring flawless operation and safety. Manual supervision and periodic maintenance are adopted in general, which is challenging to detect failures in advance, resulting in higher maintenance costs and operational hazards. Anomalous vibration due to system degradation or environmental factors is an early symptom of failure or potential threats. Hence, predicting the sources of such abnormal vibration will help prompt maintenance action or set a hazard-free environment. However, such condition-monitoring research studies are not common for indoor cleaning robots. To fill this gap, we proposed an automated Condition Monitoring (CM) system, predicting the abnormal vibration sources that will enhance Condition-based Maintenance (CbM) and Operational Safety. A novel vibration-based CM method is presented for mobile robots, suitable for indoor environments under typical illumination states, using a monocular camera and optical flow technique instead of their usual perception-related applications. The sources of abnormal vibration were classified as terrain, collision, loose assembly, and structural imbalance. We modelled vibration as sparse optical flow, and the change in optical flow vector displacement due to the robot’s vibration is derived from consecutive camera frames used as vibration data. A practical framework is developed adopting the One Dimensional Convolutional Neural Network (1D CNN) model to fit this vibration data and tested predicting the vibration source class with an average accuracy of 93.8%. In addition, a vibration source map (CbM map) is proposed by fusing the predicted class in the workplace environment map for real-time monitoring. The case studies conducted using our in-house-developed cleaning robot show that the proposed CM framework will help the maintenance team for CbM, operational safety, and select proper maintenance strategies.

Concordance assessment through comparison with urine cotinine: Does self-report adequately reflect passive smoking?

There is a paucity of studies evaluating passive smoking (PS) by comparing self-report (SR) and biomarkers. Our study aimed to confirm whether SR could accurately reflect PS compared to biomarkers, a golden standard for assessing the exposure of non-smokers. We used the 2014-2020 Korea National Health and Nutrition Examination Survey data and selected 29622 non-smokers aged >19 years as the study participants. The PS rate by SR was assessed during the last 7 days, and participants were interviewed to investigate their exposure at home, work, indoors, and in public places. In addition, participants having a limit of detection ≥0.5 ng/mL in urine cotinine (UC) was defined as the exposure group. All analyses reflected the weights of complex sampling. We first compared the rates of PS using biomarkers and SR, and then the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated based on biomarkers. PS exposure by UC was the highest (44.4%), and the exposure by SR was significantly lower (5.1-29.5%). Kappa and sensitivity in PS in the indoor home (HPS) were lower than those in indoor workplaces (WPS) and indoor public places (PPS). Moreover, overall sensitivity and PPV were lower, and specificity and NPV were relatively higher in accuracy. Lastly, the sensitivity was poor, and the specificity was relatively good, which means that measurement by SR would identify people who were actually exposed to PS as non-exposed. Despite exposure to PS, the use of the SR method is more likely to classify participants in the non-exposed group. Hence, to overcome measurement error in SR and reflect exposure in any place and setting, biomonitoring and SR should be performed.