Ergonomics and (air quality or sick building syndrome)

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Ergonomics and (air quality or sick building syndrome)

A quick search on 11306 by Rani Lueder, CPE

Anonymous (1989) Problem buildings: buildingassociated illness and the sick building syndrome. Occup Med. 4, 4, 575797.

(INSHT)., INSTITUTO NACIONAL DE SEGURIDAD EN EL TRABAJO, (1994) Ergonomics. Ediciones y Publicaciones, Madrid, Spain 69, , 217pp. Abstract: This manual on ergonomics contains: fundamental concepts of ergonomics; human beings and their environment; design of work places; design of work stations; illumination, colour and their effects on wellbeing; physical work (force, posture, repetitive motions); mental workload; controls and signs; noise and vibration; the thermal environment; air quality in interior spaces; machinery and tools; nutrition and work; the ergonomics of organizations (levels of mechanization and automation, functionality, participation, communications, training); working time (flexible working time, shortened week, shift work)."

ANON., (1991) Sick Building Syndrome. Safety Review (Electricity Association) 49 , 1517. Abstract: In connection with the recent establishment of a global alarm system by WHO concerning the mysterious occurrences of respiratory illnesses inside office buildings, known jointly as sick building syndrome, this article discusses this health problem and makes some recommendations for its prevention."

ARBEITSMEDIZIN., BUNDESANSTALT FUR, (1994) Medical Aspects of Modern Office Work. Bundesanstalt fur Arbeitsmedizin, Wirtschaftsverlag NW, Verlag fur Neue Wissenschaft GmbH, Bremerhaven, Germany, Tagungsbericht Nr.5 , 142pp. Abstract: These proceedings of a workshop in Germany, held on 10 September 1994, cover: visual strain from work at computers, electromagnetic fields, harmful substances, noise, lighting and climate in the office, the problems of sedentary work, subjectively perceived stress caused by work at computers, the causes and symptoms of sick building syndrome, the occurrence of musculoskeletal diseases, tasks and workload in the modern office."

ASSOCIATION., CANADIAN STANDARDS, (1989) A Guideline on Office Ergonomics. The Association, Rexdale, Ontario, Canada, Standard No. CAN/CSAZ412M89 132, , 111pp. Abstract: The contents of this Canadian standard include: basic concepts of ergonomics and their application in office systems; recommended practices regarding office equipment and furniture, the visual, acoustical and thermal environment and air quality; ergonomic analysis of an office environment."

Bachmann, M. O.; Turck, W. A.; Myers, J. E. (1995) Sick building symptoms in office workers: a followup study before and one year after changing buildings. Occup Med (Lond). 45, 1, 1115. Abstract: Influences of physical and psychosocial work environments and personal factors on sick building syndrome symptoms were investigated in 167

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clerical workers before and one year after moving from a naturally ventilated building to an artificially ventilated building. Female gender and work on visual display units were independently associated with most symptoms in the baseline survey and with the incident (new) symptoms in the followup survey. After changing buildings, the prevalences of eye, skin and fatigue symptoms increased significantly. Cold and discomfort due to stuffiness were independently associated with incident eye and respiratory symptoms. Reported domestic workloads were greater for women, but did not account for any gender differences in symptom prevalence.

BACHMANN, M.O.; TURCK, W.A.V.; MYERS, J.E., (1995) Sick Building Symptoms in Office Workers: A FollowUp Study before and One Year after Changing Buildings. Occupational Medicine 45 12, 1, 1115. Abstract: Influences of physical and psychosocial work environments and personal factors on sick building syndrome symptoms were investigated in 167 clerical workers before and one year after moving from a naturally ventilated building to an artificially ventilated building. Female gender and work on visual display units were independently associated with most symptoms in the baseline survey and with the incident (new) symptoms in the followup survey. After changing buildings, the prevalences of eye, skin and fatigue symptoms increased significantly. Cold and discomfort due to stuffiness were independently associated with incident eye and respiratory symptoms. Reported domestic workloads were greater for women, but did not account for any gender differences in symptom prevalence."

BAIN, P.; BALDRY, C., (1995) Sickness and Control in the Office the Sick Building Syndrome. New Technology, Work and Employment 10 39, 1, 1931. Abstract: Here the authors examine the unions' experience of buildingrelated sickness among their members and argue that we can no longer treat the built working environment as a neutral factor when analysing the labour process."

BakoBiro, Z.; Wargocki, P.; Weschler, C. J.; Fanger, P. O. (2004) Effects of pollution from personal computers on perceived air quality, SBS symptoms and productivity in offices. Indoor Air. 14, 3, 178187. Abstract: In groups of six, 30 female subjects were exposed for 4.8 h in a lowpolluting office to each of two conditionsthe presence or absence of 3monthold personal computers (PCs). These PCs were placed behind a screen so that they were not visible to the subjects. Throughout the exposure the outdoor air supply was maintained at 10 l/s per person. Under each of the two conditions the subjects performed simulated office work using old lowpolluting PCs. They also evaluated the air quality and reported Sick Building Syndrome (SBS) symptoms. The PCs were found to be strong indoor pollution sources, even after they had been in service for 3 months. The sensory pollution load of each PC was 3.4 olf, more than three times the pollution of a standard person. The presence of PCs increased the percentage of people dissatisfied with the perceived air quality from 13 to 41% and increased by 9% the time required for text processing. Chemical analyses were performed to determine the pollutants emitted by the PCs. The most significant chemicals detected included phenol, toluene, 2ethylhexanol, formaldehyde, and styrene. The identified compounds were, however, insufficient in concentration and kind to explain the observed adverse effects. This suggests that chemicals other than



those detected, socalled 'stealth chemicals', may contribute to the negative effects. PRACTICAL IMPLICATIONS: PCs are an important, but hitherto overlooked, source of pollution indoors. They can decrease the perceived air quality, increase SBS symptoms and decrease office productivity. The ventilation rate in an office with a 3 monthold PC would need to be increased several times to achieve the same perceived air quality as in a lowpolluting office with the PC absent. Pollution from PCs has an important negative impact on the air quality, not only in offices but also in many other spaces, including homes. PCs may have played a role in previously published studies on SBS and perceived air quality, where PCs were overlooked as a possible pollution source in the indoor environment. The fact that the chemicals identified in the office air and in the chamber experiments were insufficient to explain the adverse effects observed during human exposures illustrates the inadequacy of the analytical chemical methods commonly used in indoor air quality investigations. For certain chemicals the human senses are much more sensitive than the chemical methods routinely used in indoor air quality investigations. The adverse effects of PCgenerated air pollutants could be reduced by modifications in the manufacturing process, increased ventilation, localized PC exhaust, or personalized ventilation systems.

BALDRY, C.; BAIN, P.; TAYLOR, P., (1997) Human Resource Management. Sick Building Syndrome: Concepts, Issues and Practice, Edited by J. Rostron. E & FN Spon, London 42, , 99123. Abstract: "

BALLARD, B., (1995) How Odor Affects Performance: A Review. Proceedings of the Silicon Valley Ergonomics Conference and Exposition ErgoCon '95, San Jose, California, May 2124, 1995, Silicon Valley Ergonomics Institute, San Jose State University, San Jose, California 29, , 191200. Abstract: Research on the effects of environmental odour on human performance has been scarce, but enough has been performed to form a picture of how odours affect humans. Odours tend to affect humans through four different mechanisms: physiological, affective, stressful, and psychosomatic. Odours can cause increased heart rate, vomiting, shallow breathing, or inhibited EMG. Odours can affect EEG alpha, beta, and theta patterns, which are correlated to mood and affect. Affective states affect judgement, productivity, inter personal relations, selfimage, morale, and aggression. As a stressor, odour can raise or lower performance as described by the YerkesDodson Law. Odours are part of context, can be memory cues, and can convey information. As a psychological stimulus, odour can trigger psychogenic disorders or affect a person's sensitivity to sick building syndrome. Sensitivity to air pollution is a combination of all the ways an odour affects human performance."

Bangs, M. (1989) Experts in disarray over sick building syndromeis it 'all in the mind'? Occup Health (Lond). 41, 6, 183.

BOLAS, S.M.; CRAWFORD, J.O., (1996) The Sick Building Syndrome, Stress, and Perceived and Desired Personal Control. Contemporary Ergonomics 1996, Edited by S.A. Robertson. Taylor & Francis, London 19, , 117122. Abstract: This study, based partly upon the job demandsjobs control model, predicted that low perceived



personal control within an office environment, coupled with high work demands would predict a higher prevalence of selfreports of symptoms of the sick building syndrome (SBS). This prediction was not fulfilled. However, the introduction of the personality measure Desire for Control as an additional variable within the regressions resulted in support for the contention that it is the interaction of perceived control with the level preferred control that is the salient and consistent predictor of symptoms of SBS. Support for the job controljob demands model in relation to SBS symptoms, arose only with the inclusion of this trait. Psychological stress and dissatisfaction deriving from various workrelated sources significantly correlated with symptom measures."

BOURBEAU, J.; BRISSON, C.; ALLAIRE, S., (1996) Prevalence of the Sick Building Syndrome Symptoms in Office Workers before and after Being Exposed to a Building with an Improved Ventilation System. Occupational and Environmental Medicine 53 26, 3, 204210. Abstract: The authors aimed to find if the prevalence of symptoms associated with sick building syndrome decreased among office workers after moving to a building with improved ventilation (after controlling for potential confounders). The study population comprised 1390 workers in 1991 and 1371 workers in 1992 who represented more than 80% of the eligible population. The prevalence of most symptoms decreased when workers moved to the new building: skin (54%), respiratory system (53%), nose and throat (46%), fatigue (44%), headache (37%), eyes (23%). These findings were all significant and remained generally similar after controlling for personal, psychosocial, and work related factors. Furthermore, more than 60% of workers symptomatic in 1991 were asymptomatic in 1992 for all types of symptom. In contrast, less than 15% of workers were asymptomatic in 1991 but symptomatic in 1992 for all types of symptom. In this study, the prevalence of most symptoms usually associated with the sick building syndrome decreased by 40% to 50% after workers were transferred to a building with an improved ventilation system. The results show that it is possible to diminish the prevalence of symptoms associated with the sick building syndrome among office workers occupying a building with mechanical ventilation, air conditioning, and sealed windows."

BOURBEAU, J.; BRISSON, C.; ALLAIRE, S., (1997) Prevalence of the Sick Building Syndrome Symptoms in Office Workers before and Six Months and Three Years after Being Exposed to a Building with an Improved Ventilation System. Occupational and Environmental Medicine 54 18, 1, 4953. Abstract: The prevalence of symptoms associated with the sick building syndrome (SBS) has recently been shown to decrease by 40% to 50% among office workers six months after they were exposed to a building with an improved ventilation system. The objective of this study was to find whether the decrease in the prevalence of symptoms was maintained three years later. The study population comprised 1390 workers in 1991, 1371 in 1993, and 1359 in 1995, which represents 80% of the population eligible each year. The prevalence of most symptoms decreased by 40% to 50% in 1992 compared with 1991. This was similar in 1995. These findings were significant and remained generally similar after controlling for personal, psychosocial, and work related factors. In this study, the decrease of 40% to 50% in the prevalence of most symptoms investigated six months after workers were exposed to a new building with an improved ventilation system was



maintained three years later. The results of this follow up study provide further support for a real effect of exposure to a new building with an improved ventilation system on the prevalence of symptoms associated with the SBS."

Burge, S.; Hedge, A.; Wilson, S.; Bass, J. H.; Robertson, A. (1987) Sick building syndrome: a study of 4373 office workers. Ann Occup Hyg. 31, 4A, 493504.

CAKIR, A., (1994) The Sick Building Syndrome. Zeitschrift fur Arbeitswissenschaft 48 11, 3, 164170. Abstract: 'Sick building syndrome' is a common name for unspecified health impairments such as premature fatigue or dry eyes or nose believed to be caused by the work environment. Some factors like lighting and air conditioning were identified as causes of such symptoms. In addition, the impact of personal factors, e.g. age and gender, was identified. However, organizational factors and the use of VDTs can also cause similar symptoms."

CENTRE., LONDON HAZARDS, (1990) Sick Building Syndrome. Causes, Effects and Control. London Hazards Centre Trust Ltd., London 64, , 94pp. Abstract: The office development boom of the last 25 years has been followed by an architectural revolution geared to designing energy saving buildings at all costs. The result: the modern, often sealed, open plan, fluorescent lit, synthetically furnished, artificially ventilated office in which individual workers have virtually no control over their working environment. In 1990, increasing numbers of office workers are reporting symptoms ranging from dryness of the skin, eyes, nose and throat, to tiredness, headaches and allergic and asthmatic conditions. With costs pared to the bone, essential maintenance work on air conditioning, heating, cooling and ventilation is often neglected. In the most serious cases, the failure of maintenance had led to outbreaks of the potentially fatal legionnaires' disease."

COLE, N., (1989) Outlook and Output: The Link between Office Environment and Employee Productivity. Employment Gazette 97 9, 504507. Abstract: The guiding principles for buildings continue to be safety and fitness for purpose, and these are precisely defined in the relevant statutory acts, building regulations, etc. But concern for good office design centres on lighting, ventilation, data cabling, use of space, and the relationship between employee comfort and productivity. The socalled sick building syndrome is often caused by a combination of problems. Surveys have revealed that a high proportion of workers are dissatisfied with their working environment to the extent that many believe it inhibits their job performance. Increasingly designers and/or ergonomists are being called upon to highlight the problems and suggest changes that take full account of employees' needs. A leading British designer, Manufacturing Design Services of Bradford, believes that the office interior should be designed first, around the people who will work there, and then passed over to an architect to design and structure around an agreed ideal working environment. The company also believes that all employees should be involved so as to determine each person's needs for working comfortably and efficiently. This also generates staff goodwill, which can help diffuse potential crises over relocation and refurbishment. Office design at its



best improves employee wellbeing, reduces sickness and contributes ultimately to increased profitability and profits."

Crawford, J. O.; Bolas, S. M. (1996) Sick building syndrome, work factors and occupational stress. Scand J Work Environ Health. 22, 4, 243250. Abstract: The sick building syndrome has been associated with certain buildings and environmental characteristics and is estimated to affect up to 30% of new or renovated buildings. Investigations have concentrated on physical factors, and it is only recently that psychological factors have been examined. Work and personal factors have also been considered. Occupational stress has been found to be correlated with symptoms of the sick building syndrome, but much of the research has been of a crosssectional nature, and it does not indicate whether stress is an active element or an outcome. There is a clear need for further research in this area to examine stress, personality and physical factors associated with the sick building syndrome longitudinally. There is also a clear need to assess the validity of the historical and selfreport methods used to assess the sick building syndrome.

CRAWFORD, J., (1994) A Review of Sick Building Syndrome. University of Birmingham, School of Manufacturing and Mechanical Engineering, Industrial Ergonomics Group Report 185, , 73pp. Abstract: "

CRAWFORD, J.O.; HAWKINS, L.H., (1995) Sick Building Syndrome and Occupational Stress. Contemporary Ergonomics 1995, Edited by S.A. Robertson. Taylor & Francis, London 16, , 207212. Abstract: Sick Building Syndrome (SBS) has been associated with numerous factors including for example, ventilation and indoor air pollution and the sources are clearly multifactorial. This study examines the symptoms and causes of SBS in emergency control room staff. The population was assessed using a health and comfort questionnaire, environmental monitoring and an occupational stress questionnaire. The results found that there was a high prevalence of SBS complaints, staff attributed their complaints to a dry working environment. Since new technology and new control rooms had been introduced, there was reported to be an increase in some of the SBS symptoms. The staff were experiencing a stress effect attributed to organisational managerial sources. One conclusion found in the study was that the interaction between SBS and stress needs further examination."

DIXON, J.L., (1989) The Canadian Standards Association and the New CSA National Standard on Office Ergonomics (CAN/CSAZ412M89). Proceedings of the Human Factors Association of Canada 22nd Annual Conference, Toronto, Ontario, November 2629, 1989. Human Factors Association of Canada, Mississauga, Ontario 2, , 117 124. Abstract: The CSA Technical Committee on Office Ergonomics, with representatives from industry, regulatory authorities, users and special interest groups, worked for a number of years on the writing of a national standard on office ergonomics. Technical input was also solicited from many other sources, including consultants, and CSA consumer advisory panels. The Committee was confronted with many challenges during the development of the CSA National Standard on Office



Ergonomics Z412 and these protracted the duration between project initiation and publication by over double CSA's average. Z412 is a guideline with technical requirements and practices are recommendatory in tone. The Guideline contains sections on ergonomics in office systems, office equipment, office furniture, the visual environment (ie, lighting), acoustics, the thermal environment, air quality, an ergonomic analysis, definitions, organization of work and job design and an extensive bibliography. Each section of Z412 is organized into an introduction, basic concepts, technical requirements and recommended practices. The objective of Z412 is to assist office users in choosing and spatially arranging furniture and equipment, to assess environmental conditions, and to optimize job design. A certification programme related to office ergonomics will not be offered. CSA Standards on ergonomics can play a positive role in providing guidance to workers and others. In the future, CSA plans to write standards on ergonomics and standards that have important ergonomic implications."

DRANSFELD, D.; SCHACKE, G.; FUCHS, A., (1995) A Case of Sick Building Syndrome? Zentralblatt fur Arbeitsmedizin, Arbeitsschutz, Prophylaxe und Ergonomie 45 12, 5, 197201. Abstract: Following a single shorttime exposure to a mixture of solvents containing xylene and cyclohexanone on the occasion of previous floor sealing of the gymnasium of a school, a 46year old teacher complained of symptoms of the central nervous, the cardiac and the respiratory systems. The symptoms continued for more than four months, and increased when the subject remained at the school, even without further exposure. This case shows the importance of diagnostic and differential diagnostic examinations which are necessary in the context of an occupational accident. A qualitative and quantitative examination of exposure conditions, specific analyses of dangerous substances in biological material and a detailed neuropsychiatric examination are required before considering the diagnosis of a sick building syndrome or a socalled multiple chemical sensitivity (MCS)."

EXECUTIVE., HEALTH AND SAFETY, (1995) How to Deal with Sick Building Syndrome. Guidance for Employers, Building Owners and Building Managers. HSE Books, Sudbury, Suffolk 15, , 32pp. Abstract: This booklet explains what Sick Building Syndrome is and what we know about the symptoms and the possible causes. It gives general advice on how to prevent it and how, if the symptoms occur, you can systematically investigate the problem and identify reasonably practicable improvements. The advice is aimed primarily at employers, building owners and building managers; but building designers, planners, architects, engineers, furnishers and suppliers may also find it useful. Part 1 explains how to identify and investigate the problem. Part 2 gives more detailed advice on how to create a good work environment."

Fang, L.; Wyon, D. P.; Clausen, G.; Fanger, P. O. (2004) Impact of indoor air temperature and humidity in an office on perceived air quality, SBS symptoms and performance. Indoor Air. 14 Suppl 7, 7481. Abstract: Perceived air quality (PAQ), sick building syndrome (SBS) symptoms and performance of office work were studied in a real office space at three levels of air temperature and humidity and two levels of



ventilation rate (20 degrees C/40%, 23 degrees C/50%, 26 degrees C/60% RH at 10 l s(1) p(1) outside air, and 20 degrees C/40% RH at 3.5 l s(1) p(1) outside air). Thirty female subjects participated in the experiment. They were exposed to each environmental condition for 280 min. Thermal comfort was maintained at different thermal environments by selfadjustment of clothing. The subjects performed simulated office work throughout each exposure and repeatedly marked a set of visualanalog scales to indicate their perception of environmental conditions and of the intensity of SBS symptoms at the time. The study confirmed the previously observed impact of temperature and humidity on perceived air quality and the linear correlation between acceptability and enthalpy. The impact on perceived air quality of decreasing the ventilation rate from 10 to 3.5 l s(1) per person could be counteracted by a decrement of temperature and humidity from 23 degrees C/50% RH to 20 degrees C/40% RH. Performance of office work was not significantly affected by indoor air temperature and humidity. However, several SBS symptoms were alleviated when the subjects worked at low levels of air temperature and humidity, which implies that a longer term exposure to low indoor air temperature and humidity might help to improve the performance of office work. PRACTICAL IMPLICATIONS: The findings of this study indicate the importance of indoor air temperature and humidity on perceived air quality and SBS symptoms. In practice, the required ventilation rate for comfort and health should no longer be independent of indoor air temperature and humidity.

Federspiel, C. C.; Fisk, W. J.; Price, P. N.; Liu, G.; Faulkner, D.; Dibartolomeo, D. L.; Sullivan, D. P.; Lahiff, M. (2004) Worker performance and ventilation in a call center: analyses of work performance data for registered nurses. Indoor Air. 14 Suppl 8, 4150. Abstract: We investigated the relationship between ventilation rates and individual work performance in a call center, and controlled for other factors of the indoor environment. We randomized the position of the outdoor air control dampers, and measured ventilation rate, differential (indoor minus outdoor) carbon dioxide (DeltaCO(2)) concentration, supply air velocity, temperature, humidity, occupant density, degree of understaffing, shift length, time of day, and time required to complete two different work performance tasks (talking with clients and posttalk wrap up to process information). DeltaCO(2) concentrations ranged from 13 to 611 p.p.m. We used multivariable regression to model the association between the predictors and the responses. We found that agents performed talk tasks fastest when the ventilation rate was highest, but that the relationship between talk performance and ventilation was not strong or monotonic. We did not find a statistically significant association between wrapup performance and ventilation rate. Agents were slower at the wrapup task when the temperature was high (> 25.4 degrees C). Agents were slower at wrap up during long shifts and when the call center was understaffed. PRACTICAL IMPLICATIONS: The productivity benefits of ventilation rates that exceed common standards such as ASHRAE Standard 62 may be small (02%), and other factors may have a larger impact on productivity. Understaffing and long shifts should be avoided because both showed a negative impact on performance. In this study, high temperature had the largest statistically significant impact on productivity and was caused by occupants fighting over the thermostat setpoint. Care should be taken to



avoid high temperatures in call centers. If occupants are allowed to adjust temperature setpoints, then the size and/or duration of the setpoint change should be restricted.

FORD, D., (1996) Optimal Chair Design for Industrial Control Rooms: A Human Centred Design Approach. Contemporary Ergonomics in New Zealand 1996. Proceedings of the 7th Conference of the New Zealand Ergonomics Society, Wellington, August 23, 1996, Edited by F. Darby and P. Turner. New Zealand Ergonomics Society, Palmerston North, New Zealand 7, , 155162. Abstract: An ergonomic design is proposed for VDU workstations in plant control rooms. The design is humancentred and attempts to minimise all stressors on the musculoskeletal structures of operators. The design also fulfils the requirements set out under the draft ISO standard 11064 'Control Room Ergonomics' and the requirements of the regulations of the Health and Safety in Employment Regulations (1995) section 66 'Duties of designers of plant' in relation to ergonomics. The seat is to be tilted backwards and the trunkleg angle is to be opened up to 110<SUP>o</SUP>. This will optimise the ergonomic acceptability of the workstation (plant). Then, and only then, the placement of displays and controls is considered in relation to the operator. Guidelines pertaining to minimum font size, lighting levels, indoor air quality, the thermal environment, noise control and rest breaks are also provided. The current research illustrates that ergonomics principles can be applied to existing plant when retrofits are done and hence can improve the 'fit' between people and the technologies."

FRANCK, C.; BACH, E.; SKOV, P., (1993) Prevalence of Objective Eye Manifestations in People Working in Office Buildings with Different Prevalences of the Sick Building Syndrome Compared with the General Population. International Archives of Occupational and Environmental Health 65 17, 1, 6569. Abstract: A cross sectional clinical epidemiological study was carried out among 169 office workers in four Copenhagen town halls with different prevalences of the sick building syndrome. The results were compared with those in 112 subjects randomly selected from the general population. Biomicroscopic eye manifestations, such as premature breakup of the precorneal tear film, absence of foam at the inner eye canthus and epithelial damage of the bulbar conjuctiva, were investigated together with selfreported eye complaints. Although intercorrelated, the objective eye manifestations independently were statistically associated with selfreported eye complaints in office workers. The prevalence of the objective eye manifestations was significantly elevated in office workers compared with the general population and most pronounced for the buildings with a high prevalence of the sick building syndrome (p<0.001). In the general population, subjects with a nonindustrial occupation, including office workers, had a significantly higher prevalence of objective eye manifestations than those with an industrial occupation (p=0.03), but the prevalence was still significantly lower than that among the office workers in buildings with a high prevalence of the sick building syndrome (p<0.001). Since possible confounders were found not to explain the difference in prevalence of objective eye manifestations and complaints among the two populations, it is concluded that the office environment (buildings and/or type of office work) promotes these objective changes accompanied by selfreported complaints."



Garvey, J. (1994) Developing an integrated approach to SBS (Sick Building Syndrome). Occup Health (Lond). 46, 2, 5053.

Gilbert, A. N.; Knasko, S. C.; Sabini, J. (1997) Sex differences in task performance associated with attention to ambient odor. Arch Environ Health. 52, 3, 195199. Abstract: The effects of ambient odor (pleasant, unpleasant, none); odor suggestion (present, absent); and sex of subject on mood and performance measures were explored in a 3 x 2 x 2 experimental design. A total of 40 men and 40 women performed a clerical task and a speed and accuracy task (digit deletion), filled out self evaluations of mood, predicted performance, and rated the odor quality of the test room. Ambient odor conditions significantly affected room smell ratings, but they had no effect on performance or mood. Odor suggestion produced a significant sexrelated interaction effect on the digit deletion task, irrespective of actual ambient odor. The results are discussed with respect to sex differences observed in laboratory studies and in epidemiological investigations of multiple chemical sensitivity and sick building syndrome.

GRAAFMANS, J.A.M., (1992) Ergonomics in Health Care: Working Conditions in the Operating Theatre. Enhancing Industrial Performance: Experiences of Integrating the Human Factor, Edited by H. Kragt. Taylor & Francis, London 14, , 233244. Abstract: Hospital management is often confronted with discussions concerning (re)building of the operating theatre. Criteria regarding working conditions and well being of the staff cannot easily be set. In order to get more insight, relevant aspects were studied interdependently. These were climate, illumination, acoustics, ventilation of anaesthetic gases and concentration of bacteria and dust particles in the operating room air. The influence of working postures and movements of the operating room personnel on air quality is briefly characterized. Most measurements were performed during openheart surgeries, although for some a simulation needed to be set up. Some remarkable results were found. Ventilation systems do not operate as was intended because of the heat production of the surgical team. Microcirculations orginating thereof may cause high local concentrations of anaesthetic gases and heavily contaminated spots in the incision area. The hierarchical air pressure distribution in the ward is disturbed by the intense 'traffic'. The static and dynamic load on the surgical team can give rise to complaints. Unless precautions are taken, the indoor climate cannot be comfortable and safe for everybody at the same time. Monitoring systems have to be developed to check the quality of ventilation systems, to visualize microcirculations with respect to bacteria and anaesthetic gases, and to synchronize all different registrations. Optimization of the working conditions concerned implies an indispensible cooperation between a variety of medical and technical disciplines that does not develop automatically."

Hedge, A. (2000) Where are we in understanding the effects of where we are? Ergonomics. 43, 7, 10191029. Abstract: This paper briefly reviews research studies of interest to environmental ergonomists. It includes some recent work on the health effects of office lighting, especially the effects of daylighting, fluorescent lighting and full spectrum lighting. It also covers studies of indoor air quality in offices, especially



investigations of localized air filtration and the sick building syndrome. It argues the value of a systematic, ergonomics approach to designing the built environment.

HEDGE, A., (1989) Environmental Conditions and Health in Offices. International Reviews of Ergonomics: Current Trends in Human Factors Research and Practice, Volume 3, Edited by D.J. Oborne. Taylor & Francis, London 89, , 87110. Abstract: The office is rapidly becoming the workplace of the majority of workers. Research is reviewed which shows that a variety of factors in this apparently comfortable working environment may adversely affect the health and productivity of the modern office worker. This review covers studies of the health effects of office lighting, especially the effects of fluorescent lighting. It also covers studies of indoor air quality in offices, especially investigations of the sick building syndrome. Problems associated with office technology, particularly VDTs, are mentioned but research on these is not extensively reviewed. Previous models of office evaluation research are briefly described and, based on these and other empirical studies, a systems model of office environments is presented which encompasses the complex, multifactorial nature of environmental influences on office workers' health. This model describes offices as three interlocked subsystems: environment, building and work. Workers' health may, in certain circumstances, be directly affected by any or all of these subsystems. However, it is argued that the adverse effects of office environments more typically are manifested indirectly via mediating cognitive processes which influence levels of stress and decisions about individual wellbeing."

HEDGE, A., (1992) Ecological Ergonomics: The Study of Human Work Environments. Impact of Science on Society 14, No.165, 5364. Abstract: Ecological ergonomics investigates the principles for creating and maintaining habitable and healthy work environments. This overview illustrates the multidisciplinary nature of ecological ergonomics. The field covers a diverse array of work environment factors that influence worker health, satisfaction and productivity. These factors include the effects of thermal conditions, indoor air quality, office lighting, acoustics, office technology and workplace design."

HEDGE, A., (1998) Investigating Health Complaints: Behavioral Aspects. Keeping Buildings Healthy: How to Monitor and Prevent Indoor Environmental Problems, by J.T. O'Reilly, P. Hagan, R. Gots and A. Hedge. John Wiley & Sons, New York 84, , 137162. Abstract: This chapter examines the behavioural factors that have been shown to influence the perception of indoor quality and occupant reports of indoor environmental quality (IEQ), sometimes called sick building syndrome (SBS), in offices."

HEDGE, A.; BURGE, P.S.; ROBERTSON, A.S.; WILSON, S.; HARRISBASS, J., (0) Work Related Illness in Offices: A Proposed Model of the 'Sick Building Syndrome'. Environment International 15 16, 143158. Abstract: A nationwide survey of 4,373 office workers at 47 office sites was conducted to assess the prevalence of the sick building syndrome and to investigate associated factors. The office buildings sampled included those ventilated by either natural, mechanical, or forced air, or by air conditioning or some form of comfort cooling, including fancoil, induction, and



constant or variable air volume systems. Results showed a higher prevalence of reports of workrelated symptoms of dry eyes, dry throat, stuffy/congested nose, itchy/watery eyes, runny nose, lethargy/tiredness, and headache in air conditioned buildings than in unconditioned buildings. Symptom prevalence was higher in buildings ventilated with waterbased cooling systems, e.g. fancoil or induction systems, than in buildings with allair systems. A significant relationship was found between the type of humidification used in airconditioned buildings (none, evaporative/spray, or steam) and the prevalence of itchy eyes, stuffy nose, lethargy, breathing difficulty, and chest tightness. Results also suggest that the 'sick building syndrome' is associated with a variety of individual characteristics (sex, age), occupational factors (job type, length of video display unit use, occupancy duration in building, job stress), architectural features (type of office, type of building ventilation system), and psychological processes (perceived environmental control, perceived ambient conditions, perceived environmental satisfaction). A path analytic model is presented that suggests that psychological processes mediate the association between individual, occupational, and environmental characteristics and reports of its 'sick building syndrome'."

Hedge, A.; Erickson, W.A.; Rubin, G. (1993) Effects of manmade mineral fibers in settled dust on sick building syndrome in airconditioned offices. Indoor Air'93: Health effects. Proceedings of the 6th International Conference on Indoor Air Quality and Climate, vol. 1,, Helsinki, Finland, July 48, 1993, 291296. Rani notes,

HEDGE, A.; ERICKSON, W.A.; RUBIN, G., (1991) VDT Use, Job Stress, Job Satisfaction and the Sick Building Syndrome in Offices. Designing for Everyone: Proceedings of the 11th Congress of the International Ergonomics Association, Paris, Edited by Y. Queinnec and F. Daniellou. Taylor & Francis, London, Volume 1 5, , 713715. Abstract: "

HEDGE, A.; ERICKSON, W.A.; RUBIN, G., (1992) Effects of Personal and Occupational Factors on Sick Building Syndrome Reports in AirConditioned Offices. Stress and WellBeing at Work, Edited by J.C. Quick, L.R. Murphy and J.J. Hurrell. American Psychological Association, Washington, D.C. 60, , 286298. Abstract: "

HEDGE, A.; ERICKSON, W.A.; RUBIN, G., (1993) Why Do Gender, Job Stress, Job Satisfaction, Perceived Indoor Air Quality and VDT Use Influence Reports of the Sick Building Syndrome in Offices? Work with Display Units 92, Edited by H. Luczak, A. Cakir and G. Cakir. NorthHolland, Amsterdam 13, , 4953. Abstract: The relationship among the sick building syndrome (SBS), indoor air quality, individual and occupational variables, was investigated in a survey of 4,479 workers in 27 air conditioned office buildings. The number of SBS symptoms reported by each worker was not significantly associated with worker's age, smoking status, or job grade, or with concentrations of the indoor air contaminants which were measured. The number of SBS symptoms reported by each worker was significantly associated with gender, perception of indoor air quality, hours of daily VDT use, and ratings of job satisfaction and job stress. It is suggested that these variables affect symptom reports by influencing individual susceptibility to work environment conditions."



HEDGE, A.; WILSON, S.; BURGE, P.S.; ROBERTSON, A.S.; HARRISBASS, J., (1987) Environmental, Psychological and Organizational Correlates of Employee Health in Offices: A Proposed Model. Rising to New Heights with Technology. Proceedings of the Human Factors Society 31st Annual Meeting, New York City, October 1923, 1987. The Human Factors Society, Santa Monica, California, Volume 2 , 736740. Abstract: In a survey of 4373 office workers, sampled from 47 office sites across the U.K., correlates of workrelated illness were investigated. Results showed that a variety of factors influence the prevalence of 10 workrelated symptoms which are characteristic of the 'sick building syndrome'. Path analysis was used to develop a model to represent causal associations. This model proposes that workrelated illness is affected by architectural/environmental factors, individual/psychological factors, and occupational/organizational factors. The implications of this for health promotion are outlined."

Hodgson, M. (2000) Sick building syndrome. Occup Med. 15, 3, 571585. Abstract: Dr. Hodgson summarizes what is known about human symptoms and discomfort in the built environment, and formulates several critical hypotheses that show striking parallels to the questions arising from discussions of the IEI/MCS syndrome.

Hodgson, M. J. (1989) Environmental tobacco smoke and the sick building syndrome. Occup Med. 4, 4, 735740. Abstract: Environmental tobacco smoke is of serious concern in ventilated spaces both for comfort because of its odor properties and for health reasons. Although it has not been demonstrated as the primary cause in complaints, it is frequently seen as a contributing factor. Recirculation of air with ETS, without filtration or airwashing, may in fact lead to complaints, although at an unknown frequency. Finally, the contributions of ETS to the sick building syndrome is documented, although its extent is currently unknown.

HODGSON, M.J.; FROHLIGER, J.; PERMAR, E.; TIDWELL, C.; TRAVEN, N.D.; OLENCHOCK, S.A.; KARPF, M., (1991) Symptoms and Microenvironmental Measures in Nonproblem Buildings. Journal of Occupational Medicine 33 19, 4, 527 533. Abstract: Symptoms commonly defined as the sick building syndrome were studied in a crosssectional investigation of 147 office workers in five building areas using a linearanalogue selfassessment scale questionnaire to define symptoms at a specific point in time. At the same time, the environment in the breathing zone was characterized by measuring thermal parameters (drybulb temperature, relative humidity, air speed, and radiant temperature), volatile organic compounds, respirable suspended particulates, noise and light intensity, and carbon dioxide and carbon monoxide levels. Demographic characteristics of the occupants and building characteristics were recorded. Up to 25% of the variance in regression models could be explained for mucous membrane irritation and central nervous system symptoms. These two symptom groups were related to the concentrations of volatile organic compounds, to crowding, to layers of clothing, and to measured levels of lighting intensity. Chest tightness was also related to lighting intensity. Skin complaints were related only to gender. Gender, age, and education failed to demonstrate a consistent relationship with symptom categories. This study suggests that the sick building



syndrome may have specific environmental causes, including lighting and volatile organic compounds."

HOLDSWORTH, B.; SEALEY, A., (1992) Healthy Buildings: A Design Primer for a Living Environment. Longman, Harlow, Essex 56, , 148pp. Abstract: According to the World Health Organisation, up to 30% of the world's buildings are sick they adversely affect the health of the people who live or work in them. Sick Building Syndrome is now widely recognized throughout Europe and the USA and research has shown that a cocktail of natural and manmade contaminants is responsible. There are countless examples worldwide of buildings that have been constructed to rigorous technical standards with the best quality materials and most uptodate design concepts that nonetheless fail because designers have not fully appreciated the importance of the human element: how a building feels to the people who have to live or work in it. The authors of this book have made a study of healthy buildings around the world and present their suggestions for improving the quality of buildings in the future."

INSTITUTE OF OCCUPATIONAL HEALTH (TYOTERVEYSLAITOS), HELSINKI, FINLAND., (1995) Ergonomics in Offices. Ergonomiatiedote No.3, 24pp. Abstract: Office work is constantly undergoing rapid change. The equipment is improving and the computer programs are becoming more versatile. Although directives and standards are already guiding designers to create more ergonomic tools and work aids, the users need advice and instructions to attain healthy and productive workplaces. This issue of Ergonomics Bulletin describes the problems as well as solutions in the use of the mouse as an input device in VDT work. It also gives recommendations for placing office furniture and equipment so that the workers' postures and movements can be more varied and working can be more efficient. The reasons for the sick building syndrome have been intensively studied. One article sheds light on the psychosocial factors behind this syndrome. The electric and magnetic fields in office settings have aroused much restlessness. Their health risks and the measured fields of the most common devices are also described in this issue."

JAAKKOLA, J.J.K.; MIETTINEN, P., (1995) Ventilation Rate in Office Buildings and Sick Building Syndrome. Occupational and Environmental Medicine 52 24, , 709714. Abstract: The authors' aim was to examine the relation between ventilation rate and occurrence of symptoms of the eyes, nose, throat, and skin as well as general symptoms such as lethargy and headache, often termed the sick building syndrome. A cross sectional population based study was carried out in 399 workers from 14 mechanically ventilated office buildings without air recirculation or humidification, selected randomly from the Helsinki metropolitan area. The ventilation type and other characteristics of these buildings were recorded on a site visit and the ventilation in the rooms was assessed by measuring the airflow through the exhaust air outlets in the room. A questionnaire directed at workers inquired about the symptoms and perceived air quality and their possible personal and environmental determinants (response rate 81%). The outcomes were weekly work related symptoms experienced during the previous 12 months and symptom groups defined either by their anatomical location or hypothesised mechanism. The results suggest that outdoor air ventilation rates below



the optimal (15 to 25 l/s per person) increase the risk of the symptoms of sick building syndrome with the sources of pollutants present in mechanically ventilated office buildings. The Finnish guideline value is 10 1/s per person."

JONES, P.J.; AL, ET, (1995) Internal Conditions and the Response of Office Workers. Proceedings of Workplace Comfort Forum, London, 2223 March 1995. Workplace Comfort Forum, Tunbridge Wells, Kent 5, , 11pp. Abstract: Acting on behalf of the Science and Engineering Research Council and the Department of Trade and Industry a research team, drawn from the Welsh School of Architecture and the Bartlett School of Architecture, has investigated eight airconditioned buildings. By examining the buildings and their occupants in some detail, the study has attempted to determine the nature of the previously suggested relationship between air conditioning and the symptoms of Sick Building Syndrome. It is clear that there is no hard and fast relationship between air conditioning and health. A properly configured, well maintained airconditioning system can be a healthy building. Where problems do occur they are as much likely to be related to the occupant's job and the organisation they work for, as the physical environment they occupy. The study provides no support for a relationship between pollution and short term health effects. The most likely cause of such effects is thought to lie in well appreciated aspects of thermal comfort. However, even this relationship is not simple and is likely to be mediated by many factors within the overall resourceload balance of each individual."

KIRTON, G., (1997) Office Health and Safety: A Guide to Risk Prevention. UNISON, London and City Centre, London 27, , 72pp. Abstract: This publication aims to show that offices can be very risky places to work in. Not only is there a range of physical hazards arising from the working environment including overcrowding, hot working conditions, sick building syndrome, lighting problems and so on; but many office workers also face the risks of contracting WRULDs, suffering stress and facing violent behaviour by the public. The publication provides comprehensive, uptodate information on office hazards, causes and prevention."

Kreiss, K. (1989) The epidemiology of buildingrelated complaints and illness. Occup Med. 4, 4, 575592. Abstract: The recent epidemiology of major buildingrelated complaints and illness is summarized. The variety of symptoms that have been attributed to building environments in sick building syndrome and in buildingrelated illness are described, including their likely pathophysiology and their implications for remedial action and prevention.

Ooi, P. L.; Goh, K. T.; Phoon, M. H.; Foo, S. C.; Yap, H. M. (1998) Epidemiology of sick building syndrome and its associated risk factors in Singapore. Occup Environ Med. 55, 3, 188193. Abstract: OBJECTIVES: To investigate the occurrence of sick building syndrome in a tropical city, and its relation to indoor air quality and other factors. METHODS: 2856 office workers in 56 randomly selected public and private sector buildings were surveyed. The study consisted of a self administered questionnaire assessing symptoms and perception of the physical and psychosocial environment, inspection of the building plans and premises, and measurement of



temperature, relative humidity, respirable particles, chemicals, bioaerosols, and other variables. RESULTS: Symptoms typical of the sick building syndrome were reported in 19.6% of the respondents. Multivariate modelling substantiated contributions associated with low thermal comfort, high work related stress, too much noise, a history of allergy or other medical conditions, poor lighting, young employees, and female sex. Measurements of indoor air quality or ventilation were not found to be reliable predictors of the symptoms. CONCLUSION: The survey confirmed the presence of sick building syndrome and its risk factors in the tropics. A biopsychosocial approach to the problem involving symptomatic treatment, environmental control, good ergonomic design, and stress management is recommended.

Raw, G.; Goldman, L. (1996) Sick building syndrome: a suitable case for treatment. Occup Health (Lond). 48, 11, 388391.

Seppanen, O. A.; Fisk, W. J. (2004) Summary of human responses to ventilation. Indoor Air. 14 Suppl 7, 102118. Abstract: It is known that ventilation is necessary to remove indoorgenerated pollutants from indoor air or dilute their concentration to acceptable levels. But as the limit values of all pollutants are not known the exact determination of required ventilation rates based on pollutant concentrations is seldom possible. The selection of ventilation rates has to be based also on epidemiological research, laboratory and field experiments and experience. The existing literature indicates that ventilation has a significant impact on several important human outcomes including: (1) communicable respiratory illnesses; (2) sick building syndrome symptoms; (3) task performance and productivity, and (4) perceived air quality (PAQ) among occupants or sensory panels (5) respiratory allergies and asthma. In many studies, prevalence of sick building syndrome symptoms has also been associated with characteristics of HVACsystems. Often the prevalence of SBS symptoms is higher in airconditioned buildings than in naturally ventilated buildings. The evidence suggests that better hygiene, commissioning, operation and maintenance of air handling systems may be particularly important for reducing the negative effects of HVAC systems. Ventilation may also have harmful effects on indoor air quality and climate if not properly designed, installed, maintained and operated. Ventilation may bring indoors harmful substances or deteriorate indoor environment. Ventilation interacts also with the building envelope and may deteriorate the structures of the building. Ventilation changes the pressure differences across the structures of building and may cause or prevent infiltration of pollutants from structures or adjacent spaces. Ventilation is also in many cases used to control the thermal environment or humidity in buildings. The paper summarises the current knowledge on positive and negative effects of ventilation on health and other human responses. The focus is on officetype working environment and residential buildings. PRACTICAL IMPLICATIONS: The review shows that ventilation has various positive impacts on health and productivity of building occupants. Ventilation reduces the prevalence of airborne infectious diseases and thus the number of sick leave days. In office environment a ventilation rate up to 2025 L/s per person seem to decrease the prevalence of SBSsymptoms. Air conditioning systems may increase the prevalence of SBSsymptoms relative to



natural ventilation if not clean. In residential buildings the air change rate in cold climates should not be below app. 0.5 ach. Ventilation systems may cause pressure differences over the building envelope and bring harmful pollutants indoors.

Stellman, J. M.; Klitzman, S.; Gordon, G. C.; Snow, B. R. (1985) Air quality and ergonomics in the office: survey results and methodologic issues. Am Ind Hyg Assoc J. 46, 5, 286 293. Abstract: A survey of office workers at four sites was conducted by Columbia University School of Public Health during 1981 and 1982 to explore the relationships between office working conditions and employee health. Walk through surveys of each site were conducted by the research team with joint labormanagement sponsorship. A total of 2074 nonmanagerial office workers filled out a 30minute selfadministered questionnaire at their respective workplaces. Multiple item scales were tested and constructed to measure indoor air quality and ergonomic factors. Significant differences in ergonomic conditions and air quality between the sites were observed. These differences corresponded with researcher observations prior to the surveys. Significant associations between the reported air quality and respiratory symptoms and between ergonomic factors and musculoskeletal symptoms were found. Specificity of the relationship between reports about the environment and health symptoms was demonstrated. The implications of this approach for industrial hygiene investigations of nonindustrial environments are discussed.

Wargocki, P.; Lagercrantz, L.; Witterseh, T.; Sundell, J.; Wyon, D. P.; Fanger, P. O. (2002) Subjective perceptions, symptom intensity and performance: a comparison of two independent studies, both changing similarly the pollution load in an office. Indoor Air. 12, 2, 7480. Abstract: The present paper shows that introducing or removing the same pollution source in an office in two independent investigations, one in Denmark and one in Sweden, using similar experimental methodology, resulted in similar and repeatable effects on subjective assessments of perceived air quality, intensity of sick building syndrome symptoms and performance of office work. Removing the pollution source improved the perceived air quality, decreased the perceived dryness of air and the severity of headaches, and increased typing performance. These effects were observed separately in each experiment and were all significant (P < or = 0.05) after combining the data from both studies, indicating the advantages of pollution source strength control for health, comfort, and productivity.

Wargocki, P.; Sundell, J.; Bischof, W.; Brundrett, G.; Fanger, P. O.; Gyntelberg, F.; Hanssen, S. O.; Harrison, P.; Pickering, A.; Seppanen, O.; Wouters, P. (2002) Ventilation and health in nonindustrial indoor environments: report from a European multidisciplinary scientific consensus meeting (EUROVEN). Indoor Air. 12, 2, 113128. Abstract: Scientific literature on the effects of ventilation on health, comfort, and productivity in nonindustrial indoor environments (offices, schools, homes, etc.) has been reviewed by a multidisciplinary group of European scientists, called EUROVEN, with expertise in medicine, epidemiology, toxicology, and engineering. The group reviewed 105 papers published in peerreviewed scientific journals and judged 30 as conclusive, providing sufficient information on ventilation, health effects, data processing, and reporting, 14 as providing relevant background information on the issue, 43 as relevant but non



informative or inconclusive, and 18 as irrelevant for the issue discussed. Based on the data in papers judged conclusive, the group agreed that ventilation is strongly associated with comfort (perceived air quality) and health [Sick Building Syndrome (SBS) symptoms, inflammation, infections, asthma, allergy, shortterm sick leave], and that an association between ventilation and productivity (performance of office work) is indicated. The group also concluded that increasing outdoor air supply rates in non industrial environments improves perceived air quality; that outdoor air supply rates below 25 l/s per person increase the risk of SBS symptoms, increase shortterm sick leave, and decrease productivity among occupants of office buildings; and that ventilation rates above 0.5 air changes per hour (h1) in homes reduce infestation of house dust mites in Nordic countries. The group concluded additionally that the literature indicates that in buildings with airconditioning systems there may be an increased risk of SBS symptoms compared with naturally or mechanically ventilated buildings, and that improper maintenance, design, and functioning of airconditioning systems contributes to increased prevalence of SBS symptoms.

Wargocki, P.; Wyon, D. P.; Fanger, P. O. (2004) The performance and subjective responses of callcenter operators with new and used supply air filters at two outdoor air supply rates. Indoor Air. 14 Suppl 8, 716. Abstract: A 2 x 2 replicated field intervention experiment was conducted in a callcenter providing a telephone directory service: outdoor air supply rate was adjusted to be 8% or 80% of the total airflow of 430 l/s (3.5 /h) and the supply air filters were either new or had been in place for 6 months. One of these independent variables was changed each week for 8 weeks. The interventions did not affect room temperature, relative humidity or noise level. The 26 operators were blind to conditions and each week returned questionnaires recording their environmental perceptions and Sick Building Syndrome (SBS) symptoms. Their performance was continuously monitored by recording the average talktime every 30 min. Replacing a used filter with a clean filter reduced talktime by about 10% at the high ventilation rate but had no significant effect at the low rate. Increasing the outdoor air supply rate reduced talktime by 6% with a new filter in place but increased talk time by 8% with a used filter in place. The interventions also had significant effects on some SBS symptoms and environmental perceptions. The present results indicate that increasing outdoor air supply rate and replacing filters can have positive effects on health, comfort and performance. PRACTICAL IMPLICATIONS: Supply air filters should be changed frequently not just because their airflow resistance increases progressively but because they degrade air quality with negative consequences for health, comfort and the performance of office work, all of which are factors that affect office productivity (profitability). Increasing outdoor air supply rates may only be beneficial when new filters are installed. Unwanted negative effects may be produced when used filters are in place. Filter condition (used or new) should always be recorded to make it possible to draw sound conclusions in studies of the effects of outdoor air supply rates on building occupants.

Wargocki, P.; Wyon, D. P.; Sundell, J.; Clausen, G.; Fanger, P. O. (2000) The effects of outdoor air supply rate in an office on perceived air quality, sick building syndrome (SBS) symptoms and productivity. Indoor Air. 10, 4, 222236. Abstract: Perceived



air quality, Sick Building Syndrome (SBS) symptoms and productivity were studied in a normally furnished office space (108 m3) ventilated with an outdoor airflow of 3, 10 or 30 L/s per person, corresponding to an air change rate of 0.6, 2 or 6 h1. The temperature of 22 degrees C, the relative humidity of 40% and all other environmental parameters remained unchanged. Five groups of six female subjects were each exposed to the three ventilation rates, one group and one ventilation rate at a time. Each exposure lasted 4.6 h and took place in the afternoon. Subjects were unaware of the intervention and remained thermally neutral by adjusting their clothing. They assessed perceived air quality and SBS symptoms at intervals, and performed simulated normal office work. Increasing ventilation decreased the percentage of subjects dissatisfied with the air quality (P < 0.002) and the intensity of odour (P < 0.02), and increased the perceived freshness of air (P < 0.05). It also decreased the sensation of dryness of mouth and throat (P < 0.0006), eased difficulty in thinking clearly (P < 0.001) and made subjects feel generally better (P < 0.0001). The performance of four simulated office tasks improved monotonically with increasing ventilation rates, and the effect reached formal significance in the case of texttyping (P < 0.03). For each twofold increase in ventilation rate, performance improved on average by 1.7%. This study shows the benefits for health, comfort and productivity of ventilation at rates well above the minimum levels prescribed in existing standards and guidelines. It confirms the results of a previous study in the same office when the indoor air quality was improved by decreasing the pollution load while the ventilation remained unchanged.

Wigo, H.; Knez, I. (2005) Psychological impact of air velocity variations in a ventilated room. Ergonomics. 48, 9, 10861096. Abstract: Two experiments investigated the psychological impact of two velocity conditions (constant low velocity (V1) and variations of low and high velocity (V2)) in two temperature conditions (Experiment 1: an air temperature increase from 21 degrees C to 24 degrees C; Experiment 2: an air temperature increase from 25 degrees C to 27 degrees C) in females and males, aged 16 to 18 years, under realistic classroom conditions during an exposure period of 80 min. It was predicted that the V2 room condition compared to the V1 room condition would be more beneficial for subjects' perceived room temperature and air quality, selfreported affect and cognitive performance. The results obtained showed no significant effects on cognitive performance. However and as predicted, in Experiment 1, the subjects in the V2 compared to those in the V1 room condition felt that the air temperature decreased (while it de facto increased) and reported a constant level of high activation. In Experiment 2, the subjects in the V2 room condition felt that the air temperature increased less and reported that their unactivated unpleasantness increased less and activated pleasantness decreased less than it did for subjects in the V1 room condition. All this indicates, as was suggested by Wigo et al. (2002), that a cooling effect, induced by air velocity variations, might be beneficial for subjects in a ventilated room and that their perceived pleasantness of the indoor climate could be met at a higher room temperature than otherwise.

Witterseh, T.; Wyon, D. P.; Clausen, G. (2004) The effects of moderate heat stress and open plan office noise distraction on SBS symptoms and on the performance of office work.



Indoor Air. 14 Suppl 8, 3040. Abstract: Three air temperatures (22/26/30 degrees C) and two acoustic conditionsquiet (35 dBA) or openplan office noise (55 dBA)were established in an office. Thirty subjects aged 1829 years (16 male), clothed for thermal neutrality at 22 degrees C, performed simulated office work for 3 h under all six conditions. Many more (68% vs. 4%) were dissatisfied with noise in the noise condition (P < 0.01). Warmth decreased thermal acceptability (P < 0.001) and perceived air quality (P < 0.01) and increased odour intensity (P < 0.05) and stuffiness (P < 0.01). After 2 h, some forehead sweating was observed on 4, 36 and 76% of subjects (P < 0.001) at 22, 26 and 30 degrees C, while 0, 21 and 65% felt "warm" (P < 0.001). Raised temperature increased eye, nose and throat irritation (P < 0.05), headache intensity (P < 0.05), difficulty in thinking clearly (P < 0.01) and concentrating (P < 0.01), and decreased selfestimated performance (P < 0.001). Noise increased fatigue (P < 0.05) and difficulty in concentrating (P < 0.05) but did not interact with thermal effects on subjective perception. In an addition task, noise decreased workrate by 3% (P < 0.05), subjects who felt warm made 56% more errors (P < 0.05) and there was a noisetemperature interaction (P < 0.01): the effect of warmth on errors was less in the noise condition. Typing speed (P < 0.05) and reading speed (P < 0.05) were higher in noise. PRACTICAL IMPLICATIONS: This paper demonstrates that open office noise distraction, even at the realistic level of 55 dBA, increases fatigue and has many negative effects on the performance of office work, as does a moderately warm air temperature. These findings may be used to provide economic justification for the provision of private offices and air temperature control in hot weather. The additional finding that noise distraction and heat stress can sometimes counteract each other in the short term is of academic interest only, as they both increase subjective distress and fatigue. In practice, neither should be deliberately introduced to counteract the other.

Zandvliet, D. B.; Straker, L. M. (2001) Physical and psychosocial aspects of the learning environment in information technology rich classrooms. Ergonomics. 44, 9, 838857. Abstract: This paper reports on a study of environments in emerging Internet classrooms. At issue for this study is to what extent these 'technological classrooms' are providing a positive learning environment for students. To investigate this issue, this study involved an evaluation of the physical and psychosocial environments in computerized school settings through a combination of questionnaires and inventories that were later crossreferenced to case studies on a subset of these classrooms. Data were obtained from a series of physical evaluations of 43 settings in 24 school locations in British Columbia, Canada and Western Australia. Evaluations consisted of detailed inventories of the physical environment using the Computerised Classroom Environment Inventory (CCEI): an instrument developed specifically for this study. Data on psychosocial aspects of the environment were obtained with the What is Happening in this Class? (WIHIC) questionnaire administered to 1404 high school students making routine use of these computerized classrooms. Potential deficiencies in the physical environment of these locations included problems with individual workspaces, lighting and air quality, whereas deficiencies in the psychosocial environment were confined to the dimension of Autonomy. Further analysis of these



classroom environment data indicated that student Autonomy and Task orientation were independently associated with students' Satisfaction with learning and that many physical (e.g. lighting and workspace dimensions) and psychosocial factors (e.g. students' perceptions of Cooperation and Collaboration) were also associated. The results provide a descriptive account of the learning environment in 'technologyrich' classrooms and, further, indicate that ergonomic guidelines used in the implementation of IT in classrooms may have a positive influence on the learning environment.

Ergonomics and (air quality or sick building syndrome)

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