Indoor Work Environments Research Articles

Exploring gender differences in acoustic-thermal comfort and performance in a simulated working environment

This study investigated gender differences in acoustic-thermal comfort and cognitive performance in three workload levels in eight simulated work environments with two noise levels (55 and 75 dBA) and four air temperatures (18, 22, 26, and 30 °C). Subjective perceptions, including noise annoyance and fatigue, physiological measurements like Heart Rate Variability (HRV), respiration rate, and EEG variables (ALPHA, BETA, THETA) were used to assess comfort. In addition, the cognitive performance of men and women was evaluated on three levels: simple, medium, and complex. Women generally reported higher annoyance levels than men, especially at 75 dB noise level and increasing temperatures. Women experienced higher fatigue in warmer conditions than men. Women exhibited higher accuracy and lower reaction time than men at 18 °C and 22 °C with a quiet noise level (55 dBA) and simple and medium tasks. However, women acted accurately in complex tasks but had a higher reaction time. On the contrary, as the tasks are complicated and air temperature (26 °C and 30 °C) increases, men have higher accuracy and further reaction time than women. Accuracy and reaction time were diminished in both genders at 75 dBA noise level. Significant changes in the physiological parameters were observed at 18–22 °C for men and at 26–30 °C for women with the same noise level. Women had higher alpha and beta waves at 18–22 °C, indicating greater comfort and alertness, but these values decreased as air temperature rose. Overall, the study emphasizes the importance of considering gender differences when designing indoor work environments for optimal comfort and performance.

Evaluating the influence of ambient conditions in the cooking space of railway pantry car using selected thermal indices and physiological parameter.

Hot and humid indoor environment of the kitchen affects worker performance. The Indian Railway's pantry car culinary is one of them that cooks food for the on-board passengers, which could be bothered by the hot indoor climate. The current study aimed to identify the indoor working environment of the railway "pantry car" using heat stress indices such as "Universal Thermal Climate Index-UTCI," "Wet-Bulb Globe Temperature-WBGT," "Discomfort Index-DI," "Tropical Summer Index-TSI," "Heat Index-HI," and Heart Rate-HR with clothing insulation. METHODS: The study was performed in 2018 (August-summer season) to collect field survey data on 6 railway pantry cars. Measurements were carried out during peak cooking times such as morning "7 : 00 am", day "11 : 30 am", evening "4 : 00 pm," and night "6 : 30 pm". This study's descriptive and Pearson's correlation analysis was accomplished using SPSS version 2016 software. The analysis results revealed that the average values were for UTCI (37.77±5.26°C), WBGT (30.42±2.28°C), DI (30.05±2.70°C), TSI (33.21±2.90°C), HI (48.53±4.86°C), correspondingly. During analysis, the strongest correlation association was observed between "TSI and DI" (r = 0.985, p < 0.000) and WBGT and TSI (r = 0.958, p < 0.000). A "significant correlation" was found between UTCI and HI (r = 0.637, p < 0.05). While no signification correlation was found between "heat stress indices and physiological parameters (p > 0.05)". In this study, all the heat stress index limit values showed highly harsh working conditions inside the pantry car, which created unfavorable circumstances for the culinarians. Inappropriate "ventilation design" could be a reason for discomfort in the railway pantry car.

Determination of volatile organic compounds (VOCs) in indoor work environments by solid phase microextraction-gas chromatography-mass spectrometry

Volatile organic compounds (VOCs) are continuously emitted into the atmosphere from natural and anthropogenic sources and rapidly spread from the atmosphere to different environments. A large group of VOCs has been included in the class of air pollutants; therefore, their determination and monitoring using reliable and sensitive analytical methods represents a key aspect of health risk assessment. In this work, an untargeted approach is proposed for the evaluation of the exposure to volatile organic compounds of workers in an engine manufacturing plant by GC–MS measurements, coupled with solid-phase microextraction (SPME). The analytical procedure was optimized in terms of SPME fiber, adsorption time, desorption time, and temperature gradient of the chromatographic run. For the microextraction of VOCs, the SPME fibers were exposed to the air in two different zones of the manufacturing factory, i.e., in the mixing painting chamber and the engine painting area. Moreover, the sampling was carried out with the painting system active and running (system on) and with the painting system switched off (system off). Overall, 212 compounds were identified, but only 17 were always present in both zones (mixing painting chamber and engine painting area), regardless of system conditions (on or off). Finally, a semi-quantitative evaluation was performed considering the peak area value of the potentially most toxic compounds by multivariate data analyses.

Factors associated with vitamin D deficiency in health care workers exposed to SARS-CoV-2: a cross-sectional study.

Globally, up to 76.6% of the population may be affected by vitamin D (VD) deficiency, which has been linked to increased morbidity and mortality from COVID-19. This underscores the importance of further research into VD supplementation, particularly for health care workers, who are at higher risk due to indoor work environments and dietary challenges associated with shift schedules. This study aimed to identify factors associated with VD deficiency in Mexican health care workers exposed to SARS-CoV-2. We conducted a cross-sectional study from June 2020 to January 2021 among frontline health care workers treating hospitalized COVID-19 patients. Blood samples were collected to measure 25-hydroxy VD levels via radioimmunoassay. We also assessed previous COVID-19 infection and comorbidities that could influence VD levels. The study included 468 health care workers. The median serum VD concentration was 16.6 ng/mL. VD deficiency was found in 69.4% (n = 325) of participants, while only 5.1% (n = 24) had normal levels. Those with type 2 diabetes (13.3 ng/mL vs. 17.1 ng/mL) or obesity (15.7 ng/mL vs. 17.1 ng/mL) had significantly lower VD levels than their counterparts (p < 0.001 and p = 0.049, respectively). No significant differences were found among participants with high blood pressure. Multivariate analysis revealed that type 2 diabetes was independently associated with VD deficiency. There is a high prevalence of VD deficiency among health care workers, which is potentially linked to both personal health factors and occupational conditions.

3D Absolute pose estimation of a staircase cleaning robot utilizing staircase geometry and minimal low-cost sensors

Thanks to its shape-shifting abilities, the sTetris robot can climb stairs while performing the cleaning task. The sTetris robot’s overall system operation depends on localization and positioning data, which are essential for its goal of autonomously navigating multi-floor environments. The mobile robots designed to work indoors generally rely on external systems for localization information. Regretfully, this frequently requires additional hardware fixing or changes to the indoor working environment in order to achieve accurate three-dimensional (3D) position and orientation (pose) for successful operation of the mobile platform. Nonetheless, the robot can be localized on the staircase by utilizing the information of the staircase’s geometry measurements, which are known ahead of time. This article demonstrates how the known geometry of staircases and measurements from minimal number of sensors can be used to accomplish 3D pose of the robot. Experiments carried out on a real robot in an authentic indoors setting successfully demonstrate the effectiveness of the suggested approach.

Air Quality Analysis of Indoor Working Environments from Different Industries and Regions of Punjab

Background: Air pollution is a major health hazard and one of most crucial environmental aspects which cause mass mortality of population. Workers in different factories often directly exposed to particulate matter which can initiate respiratory related problems which may steer to incidence of cancer. Materials and Methods: Various particulate matter (PM) fractions and gaseous emissions were monitored in indoor environments of different industries using DRX Aerosol Monitor. Parallel monitoring of PM2.5 was performed in outdoor air by using TSI DUSTTRAK. Besides, analyses of indoor environment of different industrial units for volatile organic carbon (VOC’s), temperature, relative humidity, gaseous emissions (CO, CH4, O3, and NO2) was done by using Aeroqual. Results: The levels of particulate matter (PM) of all fractions and other criteria pollutant gases were significantly higher in all manufacturing units compared with recommended permissible WHO limits. Furthermore, PM2.5 levels were significantly higher in outdoor environment as compared to indoor workplaces at all monitored sites. Conclusion: There is a dire need to consider these high levels of PM and other gaseous emissions and take some serious steps to control this ever-increasing problem.

Rangka Kerja Konsep Elemen Reka Bentuk Biofilik (BDE) untuk Tetapan Kerja Dalaman

The human tendency to connect with nature existed long ago. Nature and humans coexist since the beginning of time indicating that constant engagement with nature is highly needed. However, due to globalization and rapid development changes has severed this relationship between human and nature. The Industrial Revolution during the 1600s created a huge gap and disconnection between human and nature, which resulted in the depletion of mental and physical wellbeing as people spend long working hours indoors. The need to stay indoors to work has led to depression and mental health degradation resulting in low performance as employees disengage from their association with nature. The importance of biophilic design elements in reducing depression and mental health degradation prevailed through evidence of research abundance. However, there are still not many studies on the framework tailored to the trend of implementing nature into the indoor working environment. This paper aims to identify, compare and characterize qualitative data from various literature source on the biophilic design elements (BDE), focusing on the indoor working environment. This study will develop a conceptual framework to determine the criteria for the most prominent biophilia elements that can be implemented in indoor settings to efficiently guide professionals in the built environment in preparing the ideal work settings. The parameters frommyriad studies encompass a variety of elements that are identified and classified by prominent researchers to reduce the impact of the inability to become in constant contact with nature. To improve productivity and reduce the stress level of the employees working indoors, the application of BDE contributes to the mood, performance and well-being of the employees, thus sustaining organization in the long run.

How many days of indoor positioning system data are required to characterise typical movement behaviours of office workers?

Indoor Positioning Systems (IPS) appear to offer great potential to study the movement and interaction of people and their working environment, including office workplaces. But little is known about appropriate durations for data collection. In this study, location observations collected from 24 office workers on a 1220 m2 office floor over a 3-month period, were analysed to determine how many days are required to estimate their typical movement and spatial behaviours. The analysis showed that up to 8 days of data was sufficient to characterise participants' typical daily movement behaviours and 10 days were required to estimate their typical spatial mobility. However, the results also indicate that 5 weeks of data collection are required to gather the necessary 10 days of data from each participant. These findings will help researchers and workplace professionals to understand the capabilities and requirements of IPS when considering their use in indoor work environments.

Performance-Oriented UWB RTLS Decision-Making Approach

When introducing new technologies, companies are repeatedly faced with choosing between solutions from different providers. Regardless of all the good technical characteristics of the technology, if it is chosen inappropriately, it can prove to be a cost driver instead of something that brings added value to the system. Aware of this, we considered selecting a real-time location system (RTLS) based on Ultra-wideband technology in the indoor work environment. In practice and theory, it has been proven that the introduction of the RTLS can have highly positive effects on performance and business sustainability indicators. When reviewing the literature, it was noticed that authors solely focus on the technical properties of the systems and prices when giving guidelines on selecting the optimal RTLS. This article aims to provide advanced guidelines for UWB RTLS selection, proposing a phased selection process which is the main novelty proposed and investigated in this research. The guidelines are based on fragmented recommendations in the scientific literature that have been identified, gathered, considered, and reasonably allocated to the advanced performance-oriented phased selection process. In practice, this approach enables decision-makers to choose the most efficient and most appropriate UWB RTLS for specific logistics systems.

Particulate matter emissions during autopsies: a method to reduce exposure

Particulate matter emitted during autopsies can serve as a vector for numerous viruses or bacteria and can lead to infections. Reducing the exposure of those particles in indoor working environments is, therefore, an important issue. To assess the health risk for employees in forensic medicine, we measure particulate matter in the ambient air during autopsies by using an aerosol spectrometer. The autopsies were performed with either an ordinary oscillating saw or an adapted saw with a suction unit. The particle emissions from both saws were compared to each other in order to evaluate whether a technical adaption leads to a particle reduction. Furthermore, the particle exposure reduction by wearing a face mask and variations in the background concentration in the room were analyzed. High particle concentrations were measured while using the ordinary saw. By using the adapted saw or wearing a face mask, the particle exposure could mostly be avoided. On the majority of the working days, an increase in the background concentration could be observed. Based on this knowledge, the use of a proper suction unit and wearing a face mask during autopsies is necessary. Besides, it is important to have sufficient ventilation in the room so that long-lasting high background concentrations can be prevented.Graphical abstract

Volatile Organic Compounds in Finnish Office Environments in 2010-2019 and Their Relevance to Adverse Health Effects.

We gathered recent (2010–2019) data on the VOC and formaldehyde levels in Finnish non-industrial indoor work environments. The data comprised 9789 VOC and 1711 formaldehyde samples collected from the indoor air of offices, schools, kindergartens, and healthcare offices. We assessed the health risks by comparing the measured concentrations to the health-based RW I/II and EU-LCI reference values. The concentrations of individual VOCs and formaldehyde in these work environments were generally very low and posed no health risks. Total VOC concentration (TVOC) as well as concentrations of several individual compounds, including aromatic compounds, alkanes, 2-ethyl-1-hexanol, and formaldehyde, showed clearly decreasing trends. In contrast, several aldehydes, acids, and a few other compounds showed increasing trends. However, the increasing trends did not seem to affect the higher ends of the distributions, as the 95th percentile values remained fairly stable or decreased over the years. The VOC patterns in the environments of the offices, schools, kindergartens, and healthcare offices varied, probably reflecting the differences in typical activities and the use of materials. However, we do not expect these differences to be relevant to health outcomes.

Indoor positioning systems to prevent the COVID19 transmission in manufacturing environments

Since the 11th of March 2020 when the World Health Organization declared the novel COVID-19 outbreak a global pandemic, it registered officially over 5 million deaths worldwide. According to the course of the pandemic, governments encouraged best practices and then ruled out temporary restrictions on daily lives. In this scenario, non-essential labor-intensive sectors were forced to put on hold operations producing massive temporary layoffs. In gradually restoring the economic activities, governments passed several laws to passively mitigate the pathogen transmission in indoor working environments. However, several COVID19-related injuries were filled by manufacturing companies. According to the outlined conditions, this paper proposes an original and advanced hardware and software architecture to prevent the COVID19 transmission in indoor production environments. The aim is to increase the safety of whichever indoor productive workplace through a contact tracing approach. Indoor positioning systems due to their ability to accurately track the movement of tagged entities compose the hardware part. For this purpose, human operatives are equipped with adequate wearable sensors. Raw data acquired are properly mined through advanced algorithms to quantitatively assess the degree of safety of any working setting. Indeed, having as a reference the epidemiological evidence the software part defines an innovative risk index along two correlated dimensions. While the first defines the risk of any worker getting infected during the shift, the other one expresses the degree of COVID19-safety of the shop floor defined by the displacements of the anchors. Benefitting from these targeted and quantitative hints, plant supervisors may redesign the production settings to lower the chances of COVID19 infection. This innovative digital framework is validated in a real case study in the North of Italy which performs manual mechanical processing for the automotive industry.

Compliance with limits of acceptability for thermal comfort, and implications for long-term comfort

This paper illustrates the derivation of a method to check whether conditions in a given indoor work environment comply or do not comply with the relevant limit of acceptability for thermal comfort. The proposed method advocates that measurement uncertainties should be ignored, as they are way too large for consistency with the existing scheme of closely-spaced thermal categories outlined in international standards. It focuses instead on the identification of a representative value of the synthetic thermal comfort index PMV to be compared with the limit of acceptability. Because indoor thermal environments, even when air-conditioned, exhibit non negligible daily and seasonal fluctuations, care must be taken to ensure that this representative value of PMV reflects thermal conditions approaching the worst case. Because the actual distribution of PMV in a given environment is unknown, the distribution of the outdoor temperature Tout is used as a proxy, and a representative value of Tout is identified in terms of a specific quantile of the summer/winter distributions. This implies that PMV can be considered adequate for comparison with limits if based on measurements carried out when the outdoor temperature is near a specified quantile of the summer/winter distributions.As a byproduct, results have been used for improving the existing methods for evaluation and assessment of long term comfort. To this aim, a more appropriate expression for weighting different exposures has been derived, and a limit of acceptability has been identified.

Optimization of method for extracting 46 volatile organic compounds (VOCs) from an activated carbon–silica gel active sampler to evaluate indoor work environments

Optimization of method for extracting 46 volatile organic compounds (VOCs) from an activated carbon–silica gel active sampler to evaluate indoor work environments

Automated activity and progress analysis based on non-monotonic reasoning of construction operations

PurposeReal-time location sensing (RTLS) systems offer a significant potential to advance the management of construction processes by potentially providing real-time access to the locations of workers and equipment. Many location-sensing technologies tend to perform poorly for indoor work environments and generate large data sets that are somewhat difficult to process in a meaningful way. Unfortunately, little is still known regarding the practical benefits of converting raw worker tracking data into meaningful information about construction project progress, effectively impeding widespread adoption in construction.Design/methodology/approachThe presented framework is designed to automate as many steps as possible, aiming to avoid manual procedures that significantly increase the time between progress estimation updates. The authors apply simple location tracking sensor data that does not require personal handling, to ensure continuous data acquisition. They use a generic and non-site-specific knowledge base (KB) created through domain expert interviews. The sensor data and KB are analyzed in an abductive reasoning framework implemented in Answer Set Programming (extended to support spatial and temporal reasoning), a logic programming paradigm developed within the artificial intelligence domain.FindingsThis work demonstrates how abductive reasoning can be applied to automatically generate rich and qualitative information about activities that have been carried out on a construction site. These activities are subsequently used for reasoning about the progress of the construction project. Our framework delivers an upper bound on project progress (“optimistic estimates”) within a practical amount of time, in the order of seconds. The target user group is construction management by providing project planning decision support.Research limitations/implicationsThe KB developed for this early-stage research does not encapsulate an exhaustive body of domain expert knowledge. Instead, it consists of excerpts of activities in the analyzed construction site. The KB is developed to be non-site-specific, but it is not validated as the performed experiments were carried out on one single construction site.Practical implicationsThe presented work enables automated processing of simple location tracking sensor data, which provides construction management with detailed insight into construction site progress without performing labor-intensive procedures common nowadays.Originality/valueWhile automated progress estimation and activity recognition in construction have been studied for some time, the authors approach it differently. Instead of expensive equipment, manually acquired, information-rich sensor data, the authors apply simple data, domain knowledge and a logical reasoning system for which the results are promising.

Structural determinants of HIV/STI prevalence, HIV/STI/sexual and reproductive health access, and condom use among immigrant sex workers globally.

Given stark health inequities among precarious and criminalized workers, we aimed to apply a structural determinants framework to systematically review evidence on HIV/sexually transmitted infection (STI) prevalence, access to HIV/STI/SRH services, and condom use among im/migrant sex workers (ISWs) globally. Systematic search of peer-reviewed studies published in English (2009-2019). Eligible studies reported HIV/STI, access to HIV/STI/SRH services, and/or condom use outcomes and/or lived experiences among ISWs. Quantitative and qualitative data were synthesized using a structural determinants framework. Of 425 studies screened, 29 studies from 15 countries were included. HIV prevalence ranged from 0.3 to 13.6% and varied across settings, with highest prevalence among undocumented ISWs in a high-income country (Portugal). Precarious immigration status was a structural factor associated with poorer HIV/STI outcomes, whereas qualitative narratives showed ISWs' lived experiences as strongly shaped by policing and stigma. Despite disparities, in some settings, HIV and STI prevalence were lower and odds of condom use with clients were higher among ISWs relative to non-im/migrant sex workers. This review identified a paucity of research on SRH and male and gender-diverse ISWs. Across legislative settings, criminalization of SW and im/migrant status, policing, and migration-related marginalization were prominent structural barriers to ISWs' HIV/STI/SRH access. This review identified important inequities and variation in HIV/STI prevalence among ISWs globally. Our findings highlight impacts of the intersections of migration and criminalization, and suggest a need to reform criminalized sex work laws; address punitive policing and immigration enforcement; enable safer indoor work environments; and expand community-based interventions towards promoting HIV/STI/SRH access and health equity among ISWs.

Sick building syndrome among healthcare workers and healthcare associates at observed general hospital in Slovenia.

The aim of this study was to assess the possible associations between self-perceived sick building syndrome (SBS) symptoms among healthcare workers and healthcare associates and self-perceived parameters of indoor work environment quality. The cross-sectional study was conducted from February to April 2019. Validated standardized evaluation tools (MM 040 NA Hospital 2007 and MM 040 NA Office 2007) were used for estimating the prevalence of SBS among observed populations. Chi-square and Mann-Whitney U tests for assessing possible associations in SBS symptoms between healthcare workers and associates were used. The response rate was 69.8%. The results showed a lower prevalence of six or more SBS symptoms in healthcare associates (6.4%) compared to healthcare workers (12.0%). Healthcare workers perceived the most frequent risk factors for SBS to be poor air quality, an inappropriate level of relative humidity, and inappropriate room temperature, while the least frequently self-perceived risk factors were inappropriate lighting and noise levels. This study represents a platform for further analyses - the identification of health risk factors with environmental monitoring.

Nanoparticle Exposure and Workplace Measurements During Processes Related to 3D Printing of a Metal Object.

Metal 3D printing has many potential uses within prototyping and manufacturing. Selective laser melting (SLM) is a process that uses metal powders in the micrometer range as printing material. The particle release from the entire SLM printing process is not well-studied. While the 3D printing itself often occurs in a sealed chamber, activities related to the process can potentially release harmful metal particles to the indoor working environment through resuspension of the printing powder or via incident nanoparticles generated during printing. The objective of this study was to improve the understanding of particle exposure in work processes associated with 3D printing and potential needs for interventions by a case study conducted in a 3D printing facility. In this setting, direct release and dispersion of particles throughout the workspace from processes related to metal 3D printing was investigated. The release from five activities were studied in detail. The activities included post-printing cleaning, object annealing, and preparation of new base substrate for the next printing was. Three of the five measured activities caused particles number concentrations in the working environment to increase above background levels which were found to be 8·102 cm−3. Concentrations during chamber emptying and the open powder removal system (PRS) cleaning processes increased to 104 and 5·103 cm−3, respectively, whereas grinding activity increased number concentrations to 2.5·105 cm−3. Size distributions showed that particles were mainly smaller than 200 nm. Respirable mass concentrations were 50.4 μg m−3, collected on filters. This was corroborated by respirable mass measured with a DustTrak of 58.4 μg m−3. Respirable mass concentrations were below the occupational exposure limits in Denmark for an 8 h time-weighted average.

A method for predicting the Actual Percentage of Dissatisfied (APD) through a simple proposition of thermal comfort zones in a working environment.

Over the last few decades, there has been a concern to improve the quality of indoor work environments and increase energy efficiency as people spend much of their time in such settings. This study analyzed a group of women developing sedentary activities to determine the Actual Percentage of Dissatisfied (APD) in the environment, considering that all people who voted any value other than zero on the seven-point scale are deemed dissatisfied. After this analysis, using the probit regression model, hot and cold air temperature curves were plotted so as to determine in which situation the number of people dissatisfied with the environment is minimal. The results showed an APD of 52.31%, which is different from the ADP recommended by ISO 7730 (2005) [-0.5 < PMV < + 0.5, PPD < 10% ]. The probit analysis using the cut of 10% as dissatisfied, according to category B of ISO 7730 (2005), showed a comfort temperature of 21.1°C, with a comfort temperature range from 19.61 to22.61°C. Using the fraction of people dissatisfied with the environment (52.31%) as the cutoff, when the air temperature is equivalent to 20.2°C, the lowest percentage dissatisfied by the cold and heat in the environment occurs simultaneously.

Efficient Combinations of NOMA With Distributed Antenna Systems Based on Channel Measurements for Mitigating Jamming Attacks

This article aims at proposing new efficient combinations of distributed antenna systems with nonorthogonal multiple access for combating the influence of harmful jamming on a downlink transmission system. A large set of practical channel measurements was performed in an indoor work environment in order to encompass a wide panoply of user positions, antennas, and jammer configurations. Then, three strategies were studied for the selection of subbands, antennas, and transmit powers so as to alleviate the influence of jamming. First, a configuration where the paired users are served by a unique antenna was considered. Then, two other configurations were studied, where paired users are served by two different antennas. It was shown that, in these two strategies, under specific channel and power conditions, it is possible to allow both paired users to perform successive interference cancellation (SIC) to remove interuser interference. The dual-SIC strategy, when applied with joint antenna transmission, presents a good robustness to jamming and yields important throughput gains, compared to the classical single-SIC scenario and single-antenna dual-SIC transmission.