Indoor environmental quality differences between office types in LEED-certified buildings in the US

The study compared IAQ, thermal quality, and lighting quality between 5 different office types in LEED-certified buildings in relation to employees' environmental satisfaction and their job performance. This was to provide workplaces where workers in each specific office environment could be provided with appropriate office settings regarding these IEQ criteria when organizations comply with LEED standards. The five types of office included private enclosed, private shared, open-plan with high cubicle over 5′, open-plan with low cubicle lower than 5′, and open-plan with no partitions (bullpen) offices. The study found IAQ enhanced workers' job performance in enclosed private offices more than both high cubicles and low cubicles. All four office types had higher satisfaction with the amount of light and visual comfort of light as well as more enhancement with job performance due to lighting quality than high cubicles. There was no difference in thermal quality between the five office types. IAQ and lighting quality were not different between enclosed private, enclosed shared, and bullpen office types, either. The study findings suggest a careful workplace design considering the height of partitions in LEED-certified buildings to improve employee's environmental satisfaction and job performance.     

Indoor climate, psychosocial work environment and symptoms in open-plan offices

To study the indoor climate, the psychosocial work environment and occupants' symptoms in offices a cross-sectional questionnaire survey was made in 11 naturally and 11 mechanically ventilated office buildings. Nine of the buildings had mainly cellular offices; five of the buildings had mainly open-plan offices, whereas eight buildings had a mixture of cellular, multi-person and open-plan offices. A total of 2301 occupants, corresponding to a response rate of 72%, completed a retrospective questionnaire. The questionnaire comprised questions concerning environmental perceptions, mucous membrane irritation, skin irritation, central nervous system (CNS) symptoms and psychosocial factors. Occupants in open-plan offices are more likely to perceive thermal discomfort, poor air quality and noise and they more frequently complain about CNS and mucous membrane symptoms than occupants in multi-person and cellular offices. The association between psychosocial factors and office size was weak. Open-plan offices may not be suited for all job types. PRACTICAL IMPLICATION: Open-plan offices may be a risk factor for adverse environmental perceptions and symptoms.     

Office layout affecting privacy,interaction, and acoustic quality in LEED-certified buildings

The study investigated differences in worker satisfaction and perceived job performance regarding privacy, interaction, and acoustic quality issues in personal workspaces between five office types in LEED-certified buildings. It finds that people in high cubicles showed significantly lower satisfaction and job performance in relation to visual privacy and interaction with co-workers than both enclosed private and enclosed shared office types. They also showed significantly lower satisfaction with noise level and sound privacy and lower job performance perceived by acoustic quality than enclosed private, enclosed shared, and bullpen types. The bullpen type, open-plan office without partitions, presented significantly higher satisfaction with noise level and higher performance perceived by acoustic quality than both high and low cubicles. Considering the bullpen type also showed higher satisfaction with sound privacy than the high cubicle type, high partitions don't seem to contribute to creating workspaces where people can have a secure conversation. The bullpen type didn't show any difference from the enclosed shared type in all privacy, interaction, and acoustic quality questions, indicating it may be a good option for a small office space instead of the enclosed shared type.     

Quantitative relationships between occupant satisfaction and satisfaction aspects of indoor environmental quality and building design

The article examines which subjectively evaluated indoor environmental parameters and building features mostly affect occupants' satisfaction in mainly US office buildings. The study analyzed data from a web-based survey administered to 52,980 occupants in 351 office buildings over 10 years by the Center for the Built Environment. The survey uses 7-point ordered scale questions pertaining to satisfaction with indoor environmental parameters, workspace, and building features. The average building occupant was satisfied with his/her workspace and building. Proportional odds ordinal logistic regression shows that satisfaction with all 15 parameters listed in the survey contributed significantly to overall workspace satisfaction. The most important parameters were satisfaction with amount of space (odds ratio OR 1.57, 95% CI: 1.55-1.59), noise level (OR 1.27, 95% CI: 1.25-1.29), and visual privacy (OR 1.26, 95% CI: 1.24-1.28). Satisfaction with amount of space was ranked to be most important for workspace satisfaction, regardless of age group (below 30, 31-50 or over 50 years old), gender, type of office (single or shared offices, or cubicles), distance of workspace from a window (within 4.6 m or further), or satisfaction level with workspace (satisfied or dissatisfied). Satisfaction with amount of space was not related to the gross amount of space available per person. PRACTICAL IMPLICATIONS: To maximize workspace satisfaction, designer should invest in aspects that increase satisfaction with amount of space and storage, noise level, and visual privacy. Office workers will be most satisfied with their workspace and building when located close to a window in a private office. This may affect job satisfaction, work performance, and personal and company productivity.     

夏热冬暖地区绿色建筑性能后评估研究

为了解夏热冬暖地区绿色建筑运行后实际能耗和室内环境品质，文章详细介绍了该气候区内绿色建筑主要技术的应用情况及应用效果。选取位于该气候区内共11个获得绿色建筑认证的办公建筑，通过调研实际能耗，结合用户主观问卷调研，与常规办公建筑的能耗和室内环境品质主观满意度进行了对比研究。结果表明，对于A类办公建筑，绿色建筑与常规建筑无明显差异，均略低于引导值；对于B类而言，绿色办公建筑的总能耗显著低于常规办公建筑，但与能耗指标相比二者能耗均较高，是建筑节能工作的重点。在室内环境品质满意度方面，用户对绿色建筑的满意度明显高于常规建筑，在空气品质和室内环境控制上尤为明显，光环境的差异则更多是归因于天然采光的设计，而非人工照明的优化。最后通过一个案例从节地、节能和室内环境等3个方面全面地介绍了适宜于夏热冬暖地区的绿色建筑设计。     

Identifying correlates of breaks in occupational sitting: a cross-sectional study

Office workers are commonly targeted in interventions to modify their sitting behaviour, yet there is limited evidence of the correlates of breaks in sitting to inform intervention development. This study identifies the individual, workplace and spatial configuration correlates of the frequency of breaks in sitting (number/hour) in office workers (n?=?5531) stratified by office type (private-enclosed, shared, open plan). All behaviours and potential correlates were measured via self-report using an online cross-sectional survey. Regression analyses revealed age was the only socio-demographic characteristic associated with frequency of breaks in sitting in all office types. Greater job autonomy and local connectivity were positively associated with frequency of breaks in sitting in shared and open-plan offices. In open-plan offices co-worker proximity was negatively associated with frequency of breaks in sitting. Co-worker visibility was positively associated with frequency of breaks in sitting in all office types. This study demonstrates that individual, workplace and spatial configuration factors are all associated with the frequency of breaks in sitting and that these relationships differ by office type. These observations extend prior studies that have only examined correlates at a single level (e.g. the individual). This evidence could be useful to guide future interventions in the design of workplaces to increase breaks in sitting and workers’ physical activity.     

Indoor air quality and occupant satisfaction in five mechanically and four naturally ventilated open-plan office buildings

Occupant responses and indoor environment characteristics were recorded and compared in five mechanically and four naturally ventilated open-plan office buildings by using a simple approach that enabled us to survey many buildings simultaneously. All occupant responses were obtained during one afternoon. In a pre-experiment, temperature and the concentration of CO₂ were monitored in 2–10 locations/office to evaluate the variation throughout the offices. A representative measurement point was subsequently selected and measurements of the same parameters were made during one week. All offices were monitored during the same week and occupant responses to the indoor environment were collected via the internet on the same day within that week. The temperature and the CO₂ concentration varied more and were in some cases higher in the naturally ventilated buildings, but occupant responses in terms of symptoms and adverse perceptions differed only modestly between the two building types. Although rarely supported by statistical significance, the results indicated a somewhat higher degree of satisfaction with the indoor environment and a lower prevalence/intensity of symptoms among the occupants in the naturally ventilated buildings.     

Risk factors for dissatisfaction with the indoor environment in open-plan offices: an analysis of COPE field study data

We applied binary logistic regression techniques to data collected from 779 participants in a field study of open-plan ('cubicle') offices conducted in nine buildings. Independent variables were physical conditions in the workplace, and dependent variables were derived from occupant satisfaction measures; personal characteristics were included as covariates. There was a significantly higher risk of dissatisfaction with privacy and acoustics (defined as being below the 20th percentile as opposed to being above the 80th percentile) associated with being in a small workstation, or being seated next to a window. A higher risk of dissatisfaction with ventilation was associated with being seated next to a window, temperatures substantially higher than the average neutral temperature, and a carbon dioxide concentration greater than 650 ppm. A higher risk of dissatisfaction with lighting was associated with panel heights greater than 66 inches (1.7 m), high reflected glare on computer screens, desktop illuminances outside 300-500 lux, desktop illuminance uniformity (min/max ratio) less than 0.5, and being in a workstation distant from a window. PRACTICAL IMPLICATIONS: We have demonstrated statistically significant relationships between indoor environment conditions in office spaces and environmental dissatisfaction risk. Although generally supported by prior research, not all of these risk factors are reflected in existing recommended practice documents for office design. Consideration of these findings in future revisions of such documents may be warranted.     

办公建筑照明节能设计探讨

本文在对办公建筑照明节能问题进行分析的基础上,针对现代办公建筑中常见的开敞办公区域进行了照明节能设计,并重点对节能设计中的功率密度及照明控制方式进行了详细阐述;最后介绍了办公建筑电气照明节能设计要注意的其它问题。     

Effect of green building certification on organizational productivity metrics

There is increasing interest in understanding how office accommodation affects organizational productivity. Data on metrics of engagement, job satisfaction, job performance and facility complaints for thousands of employees (n?=?14,569) of a large Canadian financial organization were analysed to explore differences in outcomes between those working in green-certified office buildings (n?=?10) and those in otherwise similar conventional buildings (n?=?10). Overall, green-certified buildings demonstrated higher scores on survey outcomes related to job satisfaction, value to clients and stakeholders, evaluation of management, and corporate engagement. There was also a tendency for manager-assessed job performance to be higher in green-certified buildings. Nevertheless, not all green-certified buildings outperformed all conventional buildings, and superior performance was not exhibited on all outcomes examined. A key observation is that such metrics are routinely recorded by organizations, but relating them to building characteristics is new. Recognition of such datasets opens up many promising avenues for buildings research.     

Personalized dynamic design of networked lighting for energy-efficiency in open-plan offices

Electric lighting consumes 19% of total electricity production worldwide. Open-plan offices constitute the majority of office stock, in which most office workers perform their daily tasks, and hence the lighting in those offices has significant impact on, not only energy usage, but also occupants’ productivity. This paper presents a unique lighting optimization approach for open-plan offices that is capable of tuning task lighting to each occupant's preference in the most energy-efficient fashion. Exploiting individual controllability of the advanced networked lighting systems, each luminaire can be dynamically actuated at a different level to realize various lighting configurations without any physical rewiring. This research formulates lighting actuation into a linear programming problem and finds the optimal light outputs for each of the luminaires that collaboratively deliver specified lighting to each workstation while using the least amount of energy. Simulations using our lighting optimization approach have shown its versatility in providing proper workstation-specific task lighting under different requirements compared to business-as-usual practices. Energy savings are generated from tuning the light levels to occupants’ needs as well as keeping unoccupied areas unlit or minimally lit with this approach.     

Do your offices pass the 4-L test?

Landscaped offices and the more straightforward open-plan offices can bring light and a sense of added spaciousness to the office worker. But noise is another matter, and occasionally ventilation may not be as efficient as one might hope. This article reports on Swedish field studies of the reactions of workpeople to their new surroundings.     

The influence of personality on user satisfaction: multi-tenant offices

Many different multi-tenant offices have arisen over the last decades, as building owners address the changing nature of the workplace – a need for users to share facilities. However, the existing literature on multi-tenant buildings from the point of view of user satisfaction is scarce, limiting input for user-centred design. This study analyses the influence of personality on user satisfaction with multi-tenant office characteristics. Data were collected through a questionnaire distributed among users of 17 different multi-tenant offices (business centres, incubators serviced offices and co-working places), which yielded 190 respondents. To determine the effects of personal characteristics, a multiple regression model was performed per office variable category. Results showed that users who are more extraverted, open to new experiences and more agreeable were overall more satisfied with the multi-tenant office characteristics. However, the effects of demographics and work-related characteristics were much larger. Men, older users and users working in an open and flexible work environment were overall more satisfied with the office characteristics. Owners, developers and managers can use these results for developing user-centred designs, optimizing the level of satisfaction in their offices.     

Lighting preferences in office spaces concerning the indoor thermal environment

The accurate prediction of the visual comfort zone in an indoor environment is difficult as it depends on many parameters. This is especially the case for large compact urban areas in which the density and shadow from neighboring buildings can limit the accessible daylighting in indoor spaces. This paper investigates the satisfaction range for illuminance regarding indoor air temperature in office buildings and the significant parameters affecting this range in six office buildings in Tehran, Iran. Lighting comfort has been evaluated by a subjective survey (509 total responses) and field measurement. The questionnaires were filled out in 146 and 109 rooms in summer and winter, respectively. The results show that the illuminance should not be less than 550 lx, while illuminance between 600 and 650 lx provides the highest satisfaction level. The satisfaction with lighting level is affected by individual parameters such as age, type of activity, and environmental parameters such as window orientation, external obscurations, and season. A relationship was observed between lighting level satisfaction and thermal condition acceptance, and the overall comfort depends more on thermal conditions than the lighting level.     

Application

The shape of the rooms, the behaviour of the ceiling to the angle of sound, the number of people accommodated in a given space—all these factors are discussed by the author in relation to measurements taken in offices in Europe and Scandinavia. The generic term ‘open-plan’ is used to describe the offices, since not everyone agrees on what consititutes a truly landscaped office. The author is a consultant with the Acoustic Advice Bureau, IR.VMA Peutz BV, of the Netherlands.     

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.     

Post occupancy evaluation of green residential buildings,in the Greater Kuala Lumpur,Malaysia

Homebuyers are now demanding green buildings over conventional buildings due to better performance, higher operating savings, and the premium satisfaction that the green buildings offer. However, whilst the supply of green buildings is increasing, the satisfaction of the occupants requires evaluation. This research investigated the satisfaction of the occupants of certified residential green buildings in the Greater Kuala Lumpur. The research was based on a cross-sectional survey questionnaire comprising 15 performance factors and 118 green building occupants. The survey forms were administered through hand delivery. The satisfaction of the occupants with respect to the ability of the buildings to accommodate the elderly and the disabled was very high. The occupants were also satisfied with the acoustics, overall lighting, layout, and overall air quality of the buildings. The factor analysis structured the performance factors into four clusters, namely, lighting, indoor environmental quality, operating cost, and spatial. The findings will be useful for the design teams because developers and city planners and the green rating certifiers and facilitators make their decisions on the prioritisation of the performance criteria of the green buildings. Whilst the data were collected in Malaysia, the information is applicable to beyond Malaysia.

     

Association of subjective health symptoms with indoor air quality in European office buildings: The OFFICAIR project

The aim of this study was to explore the association between the building-related occupants’ reported health symptoms and the indoor pollutant concentrations in a sample of 148 office rooms, within the framework of the European OFFICAIR research project. A large field campaign was performed in 37 office buildings among eight countries, which included (a) 5-day air sampling of volatile organic compounds (VOCs), aldehydes, ozone, and NO₂ (b) collection of information from 1299 participants regarding their personal characteristics and health perception at workplace using online questionnaires. Stepwise and multilevel logistic regressions were applied to investigate associations between health symptoms and pollutant concentrations considering personal characteristics as confounders. Occupants of offices with higher pollutant concentrations were more likely to report health symptoms. Among the studied VOCs, xylenes were associated with general (such as headache and tiredness) and skin symptoms, ethylbenzene with eye irritation and respiratory symptoms, a-pinene with respiratory and heart symptoms, d-limonene with general symptoms, and styrene with skin symptoms. Among aldehydes, formaldehyde was associated with respiratory and general symptoms, acrolein with respiratory symptoms, propionaldehyde with respiratory, general, and heart symptoms, and hexanal with general SBS. Ozone was associated with almost all symptom groups.     

Indoor gaseous air pollutants determinants in office buildings—The OFFICAIR project

The aim of this study was to identify determinants of aldehyde and volatile organic compound (VOC) indoor air concentrations in a sample of more than 140 office rooms, in the framework of the European OFFICAIR research project. A large field campaign was performed, which included (a) the air sampling of aldehydes and VOCs in 37 newly built or recently retrofitted office buildings across 8 European countries in summer and winter and (b) the collection of information on building and offices’ characteristics using checklists. Linear mixed models for repeated measurements were applied to identify the main factors affecting the measured concentrations of selected indoor air pollutants (IAPs). Several associations between aldehydes and VOCs concentrations and buildings’ structural characteristic or occupants’ activity patterns were identified. The aldehyde and VOC determinants in office buildings include building and furnishing materials, indoor climate characteristics (room temperature and relative humidity), the use of consumer products (eg, cleaning and personal care products, office equipment), as well as the presence of outdoor sources in the proximity of the buildings (ie, vehicular traffic). Results also showed that determinants of indoor air concentrations varied considerably among different type of pollutants.     

能照亮空间的双重功能织物

Koch Membranen GmbH Kunststofftechnologie研究室内装饰照明和吸声的织物技术专家很好地将其技术应用于公共建筑和设施以及众人交流的开敞式办公室、会议室和活动器械中。在这种情况下，一方面的挑战就是要创造出噪音最小化的环境，另一方面就是要保证舒适的灯光亮度。[编者按]