[Acoustic conditions in open plan office - Application of technical measures in a typical room]. / Warunki akustyczne w pomieszczeniach biurowych open space ­ zastosowanie srodków technicznych w typowym pomieszczeniu.

BACKGROUND: Noise in open plan offices should not exceed acceptable levels for the hearing protection. Its major negative effects on employees are nuisance and impediment in execution of work. Specific technical solutions should be introduced to provide proper acoustic conditions for work performance. MATERIAL AND METHODS: Acoustic evaluation of a typical open plan office was presented in the article published in "Medycyna Pracy" 5/2016. None of the rooms meets all the criteria, therefore, in this article one of the rooms was chosen to apply different technical solutions to check the possibility of reaching proper acoustic conditions. Acoustic effectiveness of those solutions was verified by means of digital simulation. The model was checked by comparing the results of measurements and calculations before using simulation. RESULTS: The analyzis revealed that open plan offices supplemented with signals for masking speech signals can meet all the required criteria. It is relatively easy to reach proper reverberation time (i.e., sound absorption). It is more difficult to reach proper values of evaluation parameters determined from A-weighted sound pressure level (SPLA) of speech. The most difficult is to provide proper values of evaluation parameters determined from speech transmission index (STI). Finally, it is necessary (besides acoustic treatment) to use devices for speech masking. The study proved that it is technically possible to reach proper acoustic condition. CONCLUSIONS: Main causes of employees complaints in open plan office are inadequate acoustic work conditions. Therefore, it is necessary to apply specific technical solutions - not only sound absorbing suspended ceiling and high acoustic barriers, but also devices for speech masking. Med Pr 2018;69(2):153-165.

Effect of noise on comfort in open-plan offices: application of an assessment questionnaire.

Open-plan offices account for 60% of French office workspaces. The noise levels recorded in this type of environment are much lower than those encountered in industrial workplaces. Nevertheless, surveys show that noise is considered by employees as the main source of discomfort. A first questionnaire dedicated to noise discomfort was produced in 2013 and tested on a panel made up of 217 people working in 7 French companies. Today, it also makes it possible to address the issues of fatigue related to ambient sound, but above all, the survey aims to study the differences in how ambient noise is perceived depending on the type of open-plan office. On the basis of that new version, a second survey has been conducted in 23 open-plan offices, making it possible to collect the responses from 617 employees. Most of the results of the first survey have been confirmed, with an increase in the significance of the statistical analyses. Moreover, French Standard NF S 31-199, which is currently being drafted, establishes a typology of open-plan office spaces according to the types of work done in them. Based on this typology, it appears that when dealing with the impact on noise on workers, a distinction has to be made between the types of open plan offices. Practitioner Summary: Surveys conducted in open-plan offices show that noise is considered by employees as the main source of discomfort even if the noise recorded in this type of environment is not hazardous. This work presents the result of a large survey dedicated to noise discomfort conducted in 23 open-plan offices.

The effect of slightly warm temperature on work performance and comfort in open-plan offices - a laboratory study.

The aim of the study was to determine the effect of a temperature of 29°C on performance in tasks involving different cognitive demands and to assess the effect on perceived performance, subjective workload, thermal comfort, perceived working conditions, cognitive fatigue, and somatic symptoms in a laboratory with realistic office environment. A comparison was made with a temperature of 23°C. Performance was measured on the basis of six different tasks that reflect different stages of cognitive performance. Thirty-three students participated in the experiment. The exposure time was 3.5 h in both thermal conditions. Performance was negatively affected by slightly warm temperature in the N-back working memory task. Temperature had no effect on performance in other tasks focusing on psychomotor, working memory, attention, or long-term memory capabilities. Temperature had no effect on perceived performance. However, slightly warm temperature caused concentration difficulties. Throat symptoms were found to increase over time at 29°C, but no temporal change was seen at 23°C. No effect of temperature on other symptoms was found. As expected, the differences in thermal comfort were significant. Women perceived a temperature of 23°C colder than men.

Does office space occupation matter? The role of the number of persons per enclosed office space, psychosocial work characteristics, and environmental satisfaction in the physical and mental health of employees.

The study examined the effects of office space occupation, psychosocial work characteristics, and environmental satisfaction on physical and mental health of office workers in small-sized and open-plan offices as well as possible underlying mechanisms. Office space occupation was characterized as number of persons per one enclosed office space. A total of 207 office employees with similar jobs in offices with different space occupation were surveyed regarding their work situation (psychosocial work characteristics, satisfaction with privacy, acoustics, and control) and health (psychosomatic complaints, irritation, mental well-being, and work ability). Binary logistic and linear regression analyses as well as bootstrapped mediation analyses were used to determine associations and underlying mechanisms. Employee health was significantly associated with all work characteristics. Psychosocial work stressors had the strongest relation to physical and mental health (OR range: 1.66-3.72). The effect of office space occupation on employee health was mediated by stressors and environmental satisfaction, but not by psychosocial work resources. As assumed by sociotechnical approaches, a higher number of persons per enclosed office space was associated with adverse health effects. However, the strongest associations were found with psychosocial work stressors. When revising office design, a holistic approach to work (re)design is needed.

Impact of noise on self-rated job satisfaction and health in open-plan offices: a structural equation modelling approach.

This study uses a structural equation model to examine the effects of noise on self-rated job satisfaction and health in open-plan offices. A total of 334 employees from six open-plan offices in China and Korea completed a questionnaire survey. The questionnaire included questions assessing noise disturbances and speech privacy, as well as job satisfaction and health. The results indicated that noise disturbance affected self-rated health. Contrary to popular expectation, the relationship between noise disturbance and job satisfaction was not significant. Rather, job satisfaction and satisfaction with the environment were negatively correlated with lack of speech privacy. Speech privacy was found to be affected by noise sensitivity, and longer noise exposure led to decreased job satisfaction. There was also evidence that speech privacy was a stronger predictor of satisfaction with environment and job satisfaction for participants with high noise sensitivity. In addition, fit models for employees from China and Korea showed slight differences. PRACTITIONER SUMMARY: This study is motivated by strong evidence that noise is the key source of complaints in open-plan offices. Survey results indicate that self-rated job satisfaction of workers in open-plan offices was negatively affected by lack of speech privacy and duration of disturbing noise.

Influence of partition layouts on speech privacy in open-plan offices.

Different partition layouts were compared to determine how to increase speech privacy while maintaining communication efficiency between workers in an open-plan office. A preliminary survey was used to determine current usage and conditions of partitions in open-plan offices. The survey results were used to select four partition layouts for testing: face-to-face, parallel, crossed-rod, and orthogonal. A computer modeling was used to test the partition layouts at three different partition heights: 1.2, 1.5, and 1.8 m. The modeling results showed that the parallel- and crossed-rod-type layouts offered the best speech privacy at the lowest partition height, but the differences among layouts disappeared as the partition height was increased. Furthermore, an acoustic field experiment was performed using partitions with a 1.5 m height following the ISO 3382-3 standard. The experimental results showed that the face-to-face layout resulted in the least speech privacy. Based on these results, an open-plan office needs to ensure that workers are spaced a sufficient distance apart and that they do not face each other to ensure speech privacy. Additionally, speech privacy should be considered in the design stage of the office space.

[Reducing noise nuisance in open-plan office rooms by masking unwanted sounds with pyramid-shaped sound columns]. / Zmniejszenie uciazliwosci halasu w biurowych pomieszczeniach open space przez maskowanie dzwieków niepozadanych kolumnami dzwiekowymi w ksztalcie piramid.

BACKGROUND: In order to obtain appropriate, acoustic conditions of working environment in open plan offices, it is necessary to apply quite a large acoustic treatment in these rooms (e.g., to achieve reverberation time 0.2-0.4 s). However, in cases where the background noise levels in rooms are very low (A-weighted sound pressure level <30 dB), then acoustic treatment alone may be insufficient. In such cases, it may be necessary to use a sound system that generate an "artificial" background noise (sound masking system). It is important that the sound masking system must mask the sound in many workplaces. Therefore, sound masking systems contain a large number of sound sources (loudspeakers), evenly distributed throughout the room. Most often, these loudspeakers are placed in a sound-absorbing suspended ceiling. MATERIAL AND METHODS: The article considers the possibility of reducing the number of sound masking sources by using 4-loudspeakers columns. These columns use speakers with much smaller dimensions and less power. The shape of the columns and the arrangement of the loudspeakers in the columns result in a directional radiation pattern that allows for a more even distribution of the masking sound in a room. The article provides the criterion of obtaining a uniform masking sound in the open plan offices. These criteria relate to obtaining appropriate masking sound parameters in the working area, and are based on the criterion value of the distraction distance of the room. RESULTS: The article provides the results of measurement tests of the uniformity of masking sound in the room with the use of the above-mentioned sound masking columns. CONCLUSIONS: It is possible to limit the number of standard masking sound sources in the rooms under consideration using pyramid-shaped sound columns with 4 loudspeakers are used. Med Pr. 2022;73(3):229-40.

Changing the Office Design to Activity-Based Flexible Offices: A Longitudinal Study of How Managers' Leadership Behaviours Are Perceived.

This longitudinal study examines the impact of office type on employees' perception of managers' leadership behaviours, which is an unexplored area. The expanding research related to activity-based flexible offices (AFOs) has mainly focused on employees' working conditions and health outcomes, not on the changes in leadership behaviours when moving from traditional offices to AFOs. Office workers (n = 261) from five office sites within a large Swedish government agency were included in a controlled study of a natural intervention. At four sites, traditional offices were replaced by AFOs, while workers at one site with no relocation acted as the control. The same employees rated different leadership behaviours in a web-based questionnaire at baseline and at one follow-up. The analyses showed that relocations from cell and open-plan offices to AFOs were clearly related to a decrease in the perception of relation-oriented leadership behaviours. However, coming from open-plan offices to AFOs also decreased the perception of the other leadership dimensions. As expected, the control group was stable over time in their perceptions. This emphasises the need for organisations to provide managers with prerequisites so they can keep up with behaviours that support employees' performance and health when office designs and ways of working are changed.

Objective measures of cognitive performance in activity based workplaces and traditional office types.

Distraction from the background environment while performing concentrationdemanding tasks is a common issue for office employees in shared work areas. However, few field studies have been conducted on the effects of different office types and work areas on objective measurements of cognitive performance. The first aim of the present field study was to investigate, before relocation to an activity-based workplace (ABW), differences in performance on a concentration-demanding cognitive task between individuals in shared/open-plan offices compared to cell offices. The second aim was to investigate, after relocation, how performance differs (withinperson) between different work areas within the ABW. This study included employees from five offices (n = 113), of which four relocated into an ABW. An acoustician measured the equivalent sound levels of the work areas. Data were analyzed using linear regression (aim 1) and mixed models (aim 2). Before relocation, employees working in shared/open-plan offices performed significantly worse (14%) than those in cell-offices, which had a 15 LAeq lower noise level. After relocation, employees performed significantly worse in the active zone without noise restrictions, compared to all other work areas. When shifting open-plan area from the active zone to the quiet zone cognitive performance increased significantly by 16.9%, and switching to individual working rooms increased performance by 21.9%. The results clearly demonstrate the importance for organizations to provide quiet areas or rooms with few distractions for employees working on tasks that demand concentration in an ABW. A daily drop in performance for each employee may be expensive for the organization in the long run.

Infection Spread and High-Resolution Detection of Close Contact Behaviors.

Knowledge of human behaviors is important for improving indoor-environment design, building-energy efficiency, and productivity, and for studies of infection spread. However, such data are lacking. In this study, we designed a device for detecting and recording, second by second, the 3D indoor positioning and head and body motions of each graduate student in an office. From more than 400 person hours of data. Students spent 92.2%, 4.1%, 2.9%, and 0.8% of their time in their own office cubicles, other office cubicles, aisles, and areas near public facilities, respectively. They spent 9.7% of time in close contact, and each student averagely had 4.0 close contacts/h. Students spent long time on close contact in the office which may lead to high infection risk. The average interpersonal distance during close contact was 0.81 m. When sitting, students preferred small relative face orientation angle. Pairs of standing students preferred a face-to-face orientation during close contact which means this pattern had a lower infection risk via close contact. Probability of close contact decreased exponentially with the increasing distance between two students' cubicles. Data on human behaviour during close contact is helpful for infection risk analysis and infection control and prevention.

[Computational studies of speech intelligibility in open-plan offices]. / Badania obliczeniowe zrozumialosci mowy w pomieszczeniach biurowych open space.

BACKGROUND: Noise in open-plan offices, connected with an unintentional hearing of conversations and related distraction of attention, causes annoyance of employees. The article presents the calculated range of speech intelligibility in a selected open-plan office room. MATERIAL AND METHODS: The speech transmission index (STI) was examined in a real room of 300 m3. The room was equipped with a sound absorbing suspended ceiling, acoustic screens and sound absorbing materials on the walls. Initial tests were conducted in order to verify the assumed computational model from ODEON software, as well as the geometrical and acoustic data describing the room. The verification process consisted of comparing the calculations and measurement results. In the main part of the study, the range of speech intelligibility was calculated for several locations of the speech source, i.e., areas in which the STI > 0.5. RESULTS: The results of the calculations and the results of the measurements of physical quantities, characterizing the acoustic properties of the open-plan office room (including STI), showed good agreement. For speech emission, the ranges of speech intelligibility were determined on several work stations. CONCLUSIONS: The use of calculation methods to simulate the sound field in open-plan office rooms is possible when the calibration of the room model is initially performed. Determination of the speech intelligibility range provides important information about the distance of negative acoustic interactions between work stations. This range can be used to determine the interaction between work stations or to assess various technical solutions to reduce the negative interaction. Med Pr. 2019;70(3):327-42.

Turning the Mirror on the Architects: A Study of the Open-Plan Office and Work Behaviors at an Architectural Company.

Following the rising cost of real estate and a desire to increase collaboration and communication among employees, the open-plan office has been trending over the past decades. Research about the impact of the open-plan office on humans is equivocal in endorsing this trend. The mixed results are further confounded following the specific job requirements, such as the need for privacy in jobs requiring a high level of concentration or, in contrast, the need for open workspace in jobs benefitting from team work and knowledge sharing. This study aims to understand the relationship between perceptions of three characteristics of the open-plan office (acoustical privacy, visual privacy, and office density), and the impact they yield on employees' judgment as well as affect-driven behaviors. The study benefits from the data from 456 employees located in 20 regional office locations within the same architectural firm. The restriction to employees of a design firm enables examinations of participants, who are already sensitive to the impacts of space by the nature of their work. The variables of interest included employee perception of the workspace (privacy, office density, and fit into workspace), employee rating of social relationships, self-reported mood (irritability) and optimal functioning (number of limited ability days), and work impacts (job satisfaction, work engagement, and job performance). The Model of behavior in an open-plan office setting based on affective events theory is adopted. Mediation roles of irritability and perception of fit into the workspace are examined. Structural equation modeling is applied to test the joint significance of the association between independent and dependent variables (direct effect) and the association between independent variables, mediator, and dependent variables (indirect effect). Nested structure of the data is accounted for by adjusting the standard errors for clustering. The significance of indirect and total effects is evaluated by the bootstrapping method. Our results show that working in the open-plan office limits the experience of privacy and intensifies the perception of intrusion among employees of an architectural company, mostly architects and designers. Additionally, employees' perception of lack of privacy and high office density negatively affect job satisfaction, work engagement, and internal work relation as well as increases the number of limited ability days. Interestingly, the lack of privacy and high office density seem to positively affect expressive personal relations among coworkers and job performance. We find supporting evidence for mediation roles of negative emotions, that is, irritability and perception of fit into the workspace.

Perceived Indoor Environment and Occupants' Comfort in European "Modern" Office Buildings: The OFFICAIR Study.

Indoor environmental conditions (thermal, noise, light, and indoor air quality) may affect workers' comfort, and consequently their health and well-being, as well as their productivity. This study aimed to assess the relations between perceived indoor environment and occupants' comfort, and to examine the modifying effects of both personal and building characteristics. Within the framework of the European project OFFICAIR, a questionnaire survey was administered to 7441 workers in 167 "modern" office buildings in eight European countries (Finland, France, Greece, Hungary, Italy, The Netherlands, Portugal, and Spain). Occupants assessed indoor environmental quality (IEQ) using both crude IEQ items (satisfaction with thermal comfort, noise, light, and indoor air quality), and detailed items related to indoor environmental parameters (e.g., too hot/cold temperature, humid/dry air, noise inside/outside, natural/artificial light, odor) of their office environment. Ordinal logistic regression analyses were performed to assess the relations between perceived IEQ and occupants' comfort. The highest association with occupants' overall comfort was found for "noise", followed by "air quality", "light" and "thermal" satisfaction. Analysis of detailed parameters revealed that "noise inside the buildings" was highly associated with occupants' overall comfort. "Layout of the offices" was the next parameter highly associated with overall comfort. The relations between IEQ and comfort differed by personal characteristics (gender, age, and the Effort Reward Imbalance index), and building characteristics (office type and building's location). Workplace design should take into account both occupant and the building characteristics in order to provide healthier and more comfortable conditions to their occupants.

Open plan offices as sociotechnical systems: What matters and to whom?

BACKGROUND: Open plan offices have proliferated for the past several decades with more and more workers being concentrated in office buildings. Several studies have identified a number of negative factors associated with open plan offices, and those include noise, speech interference, lack of privacy, and a perceived loss of control over work. While negative factors have been identified several times in the literature, many studies rely on either surveys or highly controlled environments. OBJECTIVE: The objective of this study was to use a quasi-naturalistic environment based on a scaled world model to test three hypotheses of the impacts of office interference on editing and web navigation performance and mental workload. METHOD: A mixed factor design was used that utilized continuous speech recordings, discontinuous speech recordings, and a quiet condition. Individual differences questionnaires were administered to measure focused attention, stress, and cognitive failures. After task completion, participants recorded mental workload ratings. RESULTS: Participants had higher performance accuracy in the document editing task across the speech interference conditions. Mental workload ratings were higher in the web navigation task in the discontinuous speech condition compared to the continuous speech condition. In contrast to the hypothesis, those reporting stronger focused attention performed more poorly across all speech conditions. Overall, the results were mixed. CONCLUSIONS: OPO work design must focus on individual differences among workers to determine how to customize design to facilitate performance.

Working conditions under multiple exposures: A cross-sectional study of private sector administrative workers.

BACKGROUND: Office workers are increasingly exposed to physical and psychosocial risk factors. OBJECTIVE: To assess the association between environmental, physical and organizational working conditions and the physical and psychosocial well-being of a sample of private sector office workers. METHODS: Musculoskeletal pain was collected from a body map and the Disabilities of the Arms, Shoulders and Hands questionnaire. The short version of the Copenhagen Psychosocial Questionnaire enabled collecting information on six job related satisfaction and dissatisfaction subscales. A checklist for ergonomics in computer work guided the analysis of ergonomic factors and measurements were taken to characterize environmental conditions. Association between exposures and outcomes was calculated using IBM SPSS Statistics 20 software. RESULTS: Significant moderate positive association was found between dissatisfaction with job psychological demands and musculoskeletal pain in the upper body (0.40; p= 0.05), as well as between postural ergonomic mismatches and dissatisfaction with job insecurity towards the future (0.42; p= 0.04). A significant moderate negative association (-0,47; p= 0.02) was found as well between satisfaction with job social support and with leadership quality and location of the work station in an open-plan office as opposed to smaller office rooms. CONCLUSIONS: The results show how raising awareness of the risk factors encountered in contemporary office work is still necessary to promote widespread improvement of working conditions, from both a physical and a psychosocial perspective.