Open-plan Research Articles

Assessing occupant behaviour in open-plan offices in Florianópolis: a case study regarding windows, lighting, and air-conditioning systems

Resumo Ainfluência do comportamento dos usuários em edificações é amplamente discutida como uma das causas para discrepâncias entre consumos energéticos esperados, durante a fase de projeto, e consumos durante a operação. Conhecer os principais motivadores para ajustes nos sistemas de edificações é imprescindível para aprimorar a modelagem desses comportamentos. O objetivo deste estudo é avaliar os principais agentes motivadores para o ajuste das janelas, luminárias e aparelhos de ar-condicionado em escritórios. Dois escritórios foram monitorados por meio de sensores que coletaram dados de qualidade do ambiente interno e comportamento de usuário. Foram consideradas influentes para a interação com sistemas de janelas a pluviometria e as temperaturas do ar externo e interno. O aumento das temperaturas interna e externa apresentou ainda mais influência na interaçãocom aparelhos de ar-condicionado. Duas foram as principais conclusões: há influência do layout dos escritórios no compartilhamento e controle das janelas e eficiência de estratégias passivas, como o uso de ventilação natural e cruzada; e há influência do aumento da temperatura interna em comparação à externa na previsibilidade de abertura de janelas e acionamento de aparelhos de ar-condicionado.

Optimising thermal-daylight performance in tropical open-plan offices: A coupled OTTV and daylight prediction approach

In tropical climates, the thermal performance of air-conditioned commercial building envelopes, particularly offices, is commonly assessed using the Overall Thermal Transfer Value (OTTV). Designing office buildings in these regions requires meticulous attention to achieve the optimum thermal-daylight balance, which often has conflicting characteristics. This study aims to enhance the thermal-daylight performance optimization process for open-plan office building envelopes in tropical climates, with Kuala Lumpur as a specific case study. The methodology involves parametric thermal and daylight simulations, incorporating an extensive global sensitivity analysis (GSA) based on the Monte Carlo method. Next, the most critical design parameters affecting daylight provision are identified and used to develop a prediction formula for daylight provision assessment. Finally, the exploration further examines the impact of dominant parameters on energy consumption across diverse urban densities. The results pinpointed the Shading Coefficient (SC1) and Window-to-Wall Ratio (WWR) as pivotal factors affecting heat gain. At the same time, obstruction angle (Theta), WWR, and Visible Transmittance (Tvis) significantly influence daylight provision. Furthermore, the developed daylight prediction formula consists of a fast method that can be coupled with OTTV to evaluate and optimise the thermal-daylight performance in the early design stage of office buildings. Moreover, the study reveals potential energy savings of up to 8 %, 4.83 %, and 4 % in very low, medium, and very high urban densities, respectively. These insights and the daylight prediction formula provide valuable tools for optimising building envelope thermal-daylight performance during the early stages of architectural design, offering practical guidance for both practitioners and researchers.

Effects of public data open on performance of government functions in China: the roles of digital economy and market economic system adopting the perspective of resource- based view

IntroductionThe emergence of the digital economy necessitates effective government guidance and regulation of enterprise behavior to ensure fair market competition. Understanding how public data open can enhance the performance of government functions is crucial, particularly in understanding the roles of key factors like the development of the digital economy and the current state of the market economic system. This study explores the effects of public data open on performance of government functions from a resource-based perspective.MethodsUsing a dataset of 237 Chinese cities from 2017 to 2021, we employed a two-way fixed-effects model to investigate the mechanisms. This includes its interaction with the development of the digital economy and the moderating role of the market economic system.ResultsThe findings reveal that public data open significantly improves performance of government functions, as validated by a multi-temporal DID model and various robustness checks. Notably, the development of the digital economy mediates this relationship, while the market economic system has a strong positive moderating effect. The effects of public data open on performance of government functions also exhibits significant variability.DiscussionRecommendations include coordinating regional public data open resource planning and allocation, enhancing public data open rules and objectives by region, and promoting synergy between public data open, development of digital economy and the market economic system.

Does background sound impact cognitive performance and relaxation states in enclosed office?

An enclosed office is defined as an individual room with full-height walls, equipped with the necessary tools and amenities to facilitate highly concentrated, independent work. Unlike open-plan offices, enclosed offices provide a more sound-controlled environment, which can be crucial for optimizing working and resting conditions. This study employed a 4 (background sound type: Quasi-white noise, running water, classical music, Chinese classical instrumental music) × 3 (sound pressure level: 40 dBA, 50 dBA, 60 dBA) factorial design to examine the effects of background sound type and pressure level on cognitive performance and relaxation states within enclosed offices. The findings indicated that increasing background sound pressure level to 60 dBA significantly impairs auditory working memory task performance; however, no significant differences were observed in auditory backward recall task performance at pressure level below 60 dBA (40 dBA or 50 dBA). The effect of background sound type on auditory working memory tasks was not found to be significant. In terms of subjective evaluations, background sound type significantly influenced participants’ experience of emotional pleasantness and dominance—the sense of control or power. Notably, exposure to classical music (“Blue Danube”) as background sound resulted in higher levels of reported emotional pleasantness and dominance. Furthermore, varying background sound pressure level significantly affected participants’ emotional arousal levels, highlighting the role of sound pressure level as a key factor in regulating emotional responses. These experimental results provide novel insight into how the acoustic environment in enclosed offices influences human behavior and perception and offer practical implications for designing and optimizing such environments.

Evaluating the relationship between visual privacy and work-process interactions in open-plan offices: a space syntax approach

PurposePrevious studies on privacy in offices have primarily focused on the characteristics of generic visibility, examining the entire visible space from each workspace in 360 degrees. Nevertheless, employees in their workspaces investigate the visual targets within their binocular vision at 120 degrees. Therefore, by adopting the affordances perspective, this study aims to examine deeply generic and targeted visibility in open-plan offices and their relationship to interactions.Design/methodology/approachThe study consisted of two phases utilizing space syntax techniques. Initially, work-process interactions of the employees were determined through the survey. The survey data underwent spatial analysis to calculate the number of work-process interactions. Subsequently, DepthMapX software was used for visibility analyses. A new Python script for DepthMapX was developed to analyse the targeted visibility ratio. Multiple regression analyses were conducted to examine the relationship between the number of work-process interactions with generic and targeted visibility parameters.FindingsThe findings revealed that a higher number of visible employees within the 120-degree and 360-degree fields of vision corresponded to a lower number of work-process interactions in open-plan offices. Furthermore, the study establishes a direct link between visual privacy and interaction, indicating that increased visibility leads to decreased visual privacy.Originality/valueThe current research concluded that the relationship between visual privacy and interaction in open-plan offices differs from the previous studies, as employees with low visual privacy and high visibility tend to engage in fewer interactions. Overall, this study highlights that increased employee visibility is not directly associated with increased interaction in open-plan offices unless adequate visual privacy is provided.

Office soundscape assessment: A model of acoustic environment perception in open-plan officesa).

The soundscape approach has been utilised in recent research for residential environments, but applications to indoor working environments remain limited. This study investigated the suitability of affective quality evaluations of open-plan office acoustics. Perceptual assessments were completed by occupants of eight open-plan office floorplates, using affective dimensions outlined in PD ISO/TS 12913-3:2019 and indoor soundscape studies. Participant demographic, contextual, work-related quality, and psychological well-being data were collected. Workstation noise levels were measured following BS ISO 22955:2021. Principal component analysis identified Pleasantness, Eventfulness, and Emptiness as the main perceptual dimensions, cumulatively explaining 56% of the total variance. Results indicate the suitability of the PD ISO/TS 12913-3:2019 two-dimensional model for open-plan offices. The perceived presence of human sounds negatively correlated with ISO Pleasantness yet positively correlated with ISO Eventfulness. Participant gender and aural diversity mediated ISO Pleasantness. Psychological well-being and work-related quality correlated positively with soundscape pleasantness. No correlations were found between level-based acoustical indicators-equivalent continuous sound level (LAeq), level exceeded 10% (LA10) and 90% (LA90) of the time, level variability (LA10-LA90) and Liveliness-and perceptual scores. A conceptual representation of open-plan office soundscape perception is presented, offering a framework for evaluating and designing workspaces to enhance well-being.

A Case Study on Occupants' Thermal and Acoustic Environmental Experiences in an Open-Plan Office - Considering Physical and Non-Physical Factors -

A Case Study on Occupants' Thermal and Acoustic Environmental Experiences in an Open-Plan Office - Considering Physical and Non-Physical Factors -

Protocols for planning micro-zones to facilitate occupant-centric control (OCC) to reduce HVAC energy consumption in Indian open-plan offices

Protocols for planning micro-zones to facilitate occupant-centric control (OCC) to reduce HVAC energy consumption in Indian open-plan offices

Beyond academia: Investigating indoor environmental quality and its impact on postgraduate student satisfaction

PurposeUniversities need to provide well-planned physical environments to foster creativity, since the indoor setting plays a crucial role in academic success in the 21st century, influencing their research efforts and future outcomes. This study set out to gain a better understanding of the relationship between Indoor Environmental Quality (IEQ) measures and occupants' fulfilment in their environments, emphasizing the significance of IEQ in improving comfort and well-being. To this end, first the indoor environmental quality (IEQ) in university open-plan research offices (UOROs) in Brunel University London, UK is assessed by measuring various environmental factors through low-cost sensors. The data is then linked to a “Right Now” survey carried out to investigate to what extent do the measured values of the IEQ factors in postgraduate rooms differ from occupant satisfaction. The research showed a significant connection between measured IEQ factors and evaluations made by occupants. Subjective assessments may not always correspond with objective measures. The findings could guide design elements for postgraduate students' use of structures, potentially enhancing productivity. The system combines sensor technologies and Arduino-based monitoring to collect real-time data, improving the comprehension of IEQ and facilitating future study and practical applications in optimizing academic environments for increased productivity and well-being.

Ventilation effectiveness and incomplete mixing in air distribution design for airborne transmission

How ventilation should be arranged to be effective at reasonable air change rates is one key question as ventilation criteria and standard airborne disease transmission models are based on the well-mixed assumption, but air distribution patterns lead to non-uniform spatial concentrations. In this study a new method for ventilation effectiveness application in ventilation design for airborne transmission was developed and tested with tracer gas measurements in 22 rooms. Contrary to existing ventilation effectiveness values measured with distributed source, the developed method uses a couple of point source locations corresponding to an infector to quantify infection risk for each occupant. Novelty of the method is new ventilation effectiveness indicator that makes it possible to describe the effect of spatial variation of concentration and risk with single parameter. Quanta were used as input data to calculate the ventilation rate supplied by air distribution system corresponding to a specified risk level, but the differences between studied cases do not significantly depend on the quanta values. Application of the method to measured rooms showed that simple ventilation effectiveness calculation from average concentration at the breathing height, not requiring quanta data, provided lower ventilation effectiveness and higher ventilation rate in all cases. In many cases the difference in required ventilation rates was only a few percent, but in some large spaces it exceeded 10% with maximum of 39% in large open plan office with high concentration differences. Measured ventilation effectiveness values ranging from 0.5 to 1.4 indicate a substantial improvement potential in many cases.

Quantifying human thermal adaptation for indoor environments through field surveys and climate chamber experiments

ABSTRACT Thermal comfort boundaries established through climate chamber experiments are often found to significantly vary in real-world conditions based on the potential for thermal adaptation. In this context, this research aims to quantify the extent of thermal adaptation using a personalized ventilation system. We hypothesize that a personalized ventilation system can enhance thermal adaptation compared to real-world settings with limited opportunity for thermal adaptation. The study is based on thermal comfort surveys in mixed-mode open-plan office spaces of a humid subtropical region (Cwa), and a controlled climate chamber with a provision for personalized ventilation. We obtained 5629 subjective thermal responses through longitudinal field surveys accompanied by environmental measurements. In a climate chamber, 16 acclimatized volunteers were subjected to 140 different set-points with air temperature (Ta), relative humidity (RH), and air velocity (Va) variations yielding 19,200 subjective responses. A thermo-neutral temperature (Tn) of 26.5°C with an acceptability band of ±5.9°C was obtained through the field surveys. The Tn obtained from climate chamber surveys varied from 28.0°C to 29.3°C with an acceptability band of ±3.6°C depending on the ventilation rate. An empirical relationship between thermal sensation vote (TSV) and multiple environmental variables (Calidity) suggests 2°C higher Tn for Caliditychamber, Thermal adaptation correction factor of 2.1°C for warm-dry indoor environment and 1°C for warm-humid indoor environment were deduced through comparative analysis.

Research on Regulation Method of Variable-Air-Volume Air Conditioning System with “Personal Space”

In large public facilities, such as airport terminals or open-plan office spaces, the HVAC system typically consumes substantial amounts of energy. However, individuals often gather at specific areas while other zones are occupied by transient or occasional users. To minimize operational energy usage, this paper aims to reduce thermal comfort demands in non-targeted areas. This paper introduces a method for regulating the thermal environment around occupants exclusively in the variable-air-volume (VAV) air conditioning running mode. The investigation utilizes Airpak modeling and experimental verification techniques. Additionally, an analysis of temperature field and velocity field distributions within the room under the “personal space” operation mode is presented. The results suggest that adjusting the numbers of air vents, openings, airflow velocities, and air supply orientations can establish a comfortable thermal environment for inhabitants and reduce the overall ADPI value. The combined air supply mode leads to a 16.7% reduction in power usage compared to traditional full-space operation.

Are open science practices in dentistry associated with higher Altmetric scores and citation rates?

AimOpen science, a set of principles and practices, aims to make scientific research more accessible and accountable, benefiting scientists and society. This study evaluated whether adopting open science practices (OSPs) correlates with higher citation rates and Altmetric scores. MethodsA random sample of randomised clinical trials (RCTs) on dental caries published between 2000 and 2022 was selected. A systematic PubMed search identified relevant RCTs, and data on OSPs - study registration, open methodology, open software, open scripts, open analysis plan, open data, open peer review, and open access (OA) - were manually collected by two independent assessors. The Robot Reviewer tool automatically evaluated the risk of bias (RoB). Outcomes included the total number of citations and the Altmetric Attention Score. Associations between OSPs, RoB, and other explanatory variables with the outcomes were assessed using binomial negative regression analysis, and expressed as Incidence Rate Ratio (IRR; α =0.05). ResultsIn total, 323 papers were analysed. At least one OSP was adopted in 57.5 % (n = 186) of the articles, dropping to 39.6 % (n = 128) without OA. Papers with protocol registration (IRR: 1.45; 95 % CI: 1.15, 1.82) and OA publication (IRR: 1.24; 95 % CI: 1.01, 1.53) had higher citation rates. Conversely, papers in full OA journals had fewer citations (IRR: 0.67; 95 % CI: 0.52, 0.87). After adjusting for RoB, low-risk studies showed higher citation rates (IRR: 1.48; 95 % CI: 1.14, 1.91), while OA lost significance. For Altmetric scores, registered and OA manuscripts showed higher scores (IRR: 3.74; 95 % CI: 2.00, 7.01; IRR: 1.69; 95 % CI: 1.04, 2.75), with registration remaining significant after adjusting for RoB and impact factor (IRR: 3.71; 95 % CI: 1.97–6.99). ConclusionThe adoption of OSPs demonstrated a partial correlation with citation rates and Altmetric scores in RCTs on dental caries; however, these effects are complex and seem more related to the journal's impact factor. Clinical significanceThe citations and the attention to clinical trials in dentistry, which could drive clinical decision-making and the elaboration of policies and recommendations, seem to be driven more by the journal's prestige than by the adoption of OSPs.

Relation between occupation density and ambient noise in open plan offices: a study based on field measurements

Although progress has been made over the last decade on the issue of well-being in open-plan offices, recent surveys show that employees are still dissatisfied with their working environment, particularly the noise environment, remains. However, standards exist to help ensure that open-plan offices are designed to provide the best possible working environment. But, because of the scope of these standards, their recommendations can be contradictory. For example, the French ergonomics standard NF X35-102 makes recommendations on the sizing of workstations, likely to lead to office occupancy densities that are incompatible with the ambient noise level objectives defined in the ISO 22955 standard. To resolve these contradictions, a field measurement protocol was implemented. It consists in (1) a real-time count of the number of people in the office, (2) a measurement of ambient noise, (3) a questionnaire assessing employees' perception of their physical working environment. The data collected in several French companies will make it possible to establish relationships between the ambient noise level, the occupancy density and the perception of noise levels. This paper presents an occupancy sensor developed for this study and measurements of ambient noise level and occupancy ratio during a working day in an open-plan office.

Exploring the potential of non-traditional sound absorbers to improve acoustic quality in open-plan offices

Open-plan offices are designed to promote collaboration and communication between workers, but they can be noisy and distracting, where irrelevant speech is one of the main causes of dissatisfaction and annoyance. To address the problem, synthetic sound absorbers are often used as one of the possible acoustic measures. However, these materials are typically derived from petrochemicals, demanding considerable energy for production, which conflicts with global agenda for decarbonization and circularity. Alternatively, non-traditional sound absorbers can replace synthetic ones, aiming to enhance acoustic quality in open-plan offices. In the present study, a real open-plan office was measured according to ISO 3382-3:2022, and the data was used to calibrate a room model in ODEON. Computer simulations were conducted to evaluate the room with different synthetic and non-traditional sound absorbers. It was observed that the non-traditional sound absorbers can attenuate office noise as effectively as synthetic sound absorbers, and improve acoustic quality criteria recommended by ISO 22955:2021. Auralizations were then conducted to assess the participants' auditory perception through a listening test with both types of sound absorbers. The ongoing listening test aims to determine whether the sustainable nature of non-traditional sound absorbers positively influences subjective experiences compared to their synthetic counterparts.

Structure of workers' impression evaluation of sound environment in open-plan office

In recent years, the shift towards open-plan offices has been gaining momentum, with the aim of enhancing intellectual productivity through improved worker communication. A wealth of research has focused on the link between the acoustic environment and intellectual productivity. Yet, the intricate factors that bridge the acoustic environment with intellectual productivity remain elusive. This study endeavors to illuminate the pivotal role of impression evaluations in bridging the gap between the acoustic environment and intellectual productivity. Through a detailed empirical analysis conducted over six days in a real-world open-plan office, we investigated both the sound environments and the workers' impression evaluation during this period. Based on the results of the survey, an evaluation structure that represents the relationship between the acoustic environment and intellectual productivity in open-plan offices was studied using structural equation modeling. The results of the analysis showed that workers of multi-person work were more susceptible to the effects of acoustic environment than individual workers.

Empirical method for predicting speech sound propagation in offices

The room acoustic parameters of ISO 3382-3 allow for an evaluation of sound propagation and speech intelligibility in open-plan offices and have increasingly been used in the planning process since their introduction in 2012. The input parameters are the speech sound pressure levels and the speech transmission indices at the workstations along a measurement path including a sound source (imaginary speaker). ISO 3382-3 is a measurement standard - a calculation method is not defined. However, it is possible to calculate the necessary input data, namely the speech sound pressure levels and the speech transmission indices, using room acoustic computer simulations. Although computing power is no longer a limiting factor today, the modeling and verification of computer models are still complex and correspondingly time and cost intensive. Hongisto and Keränen (2013, 2015) describe a model for predicting the ISO 3382-3 parameters. In this study, this prediction model was tested using measurement data from several open-plan offices in Germany. Recommendations for the application of the model are derived from preliminary investigations, and the limitations and boundaries of the method are further specified.

Design solutions to optimise acoustic requirements for specific work activities in open-plan offices

A high level of concentration is required in open-plan offices, which entails an optimized acoustic environment. The aim is to create a fit-employee environment in which speech privacy is guaranteed without compromising the sense of cooperation among occupants. The purpose of this study is to investigate the design solutions which optimize the acoustic requirements of ISO 3382-3 for a specific work activity defined in ISO 22955, such as non-collaborative work, collaborative work between people and mixed between collaborative and non-collaborative. The case study is one open-plan office occupied by 12 workers, which was not compliant with the standard. Acoustic measurements were used to calibrate the acoustic model in the Odeon software. Two screen and cubicle heights, three types of ceilings and two wall absorption configurations have been tested in a matrix of solutions for the office in the simulation model. This allowed us to investigate the design solutions that guarantee optimal values for the acoustical parameters chosen for each specific activity.

A study of noise-induced annoyance and fatigue in open-plan offices: comparison between hearing-impaired and normal-hearing listeners

Several studies outline a future scenario of longer working lives and later retirement, meaning that there could be a large number of elderly workers in offices. Add to this the natural effect of hearing loss due to ageing (presbycusis; which usually presents after the 5th decade of life) and you have an open door to questions regarding the acoustic comfort of this group. In a first study, it was shown that the effect of intelligible speech on performance in a serial recall task is similar for listeners with normal hearing and presbycusis. The aim of this new experiment is to assess whether any differences might occur when people are involved in a more ecologically valid task (long exposure to noise - 3 h/condition - and similar tasks to those performed in open-plan offices). Given the validation of a hearing loss simulator in previous studies, this one will be used to reproduce the group of people with mild hearing loss (onset of presbycusis). Therefore, the same group of people (32 participants) with normal hearing will perform the experiment under two listening conditions, with and without the simulator. Each listening condition will have two noise conditions, irrelevant speech, each with a different intelligibility level.

A revised online tool for room acoustic prediction of open-plan offices

Room acoustic conditions in open-plan offices are usually measured using ISO 3382-3 standard. The essential single-number quantities obtained from the measurement are comfort distance and distraction distance. Their values can also be predicted using a regression model of Keränen & Hongisto (2013). The prediction accuracy of the model has been proven to be high. The input variables for the model are simple to obtain: room dimensions, screen height, ceiling absorption, vertical absorption, speech level, and background noise level. The prediction model was published online in 2008 but withdrawn in 2013. Since then, we have been repeatedly asked to return the online tool. Since the standard was updated in 2022, we developed a revised online tool that predicts the single-number values of ISO 3382-3 standard. The purpose of this study is to present the online tool and validate its reliability by comparing online tool results to previously published results. The comparison shows that the online tool results agree with the above-mentioned studies. Therefore, the online tool can be safely used. It is a valuable aid in workplace design, demonstrations, research, and education.