Office work and physical factors : health aspects of electromagnetic fields and light
The overall aim of this thesis is to increase our knowledge of the physical environment of office workers with special focus on electromagnetic fields and to address the question of whether electromagnetic fields can directly or indirectly contribute to symptoms or discomfort among video display ter...
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Umeå universitet, Yrkes- och miljömedicin
1997
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ftumeauniv:oai:DiVA.org:umu-96906 2024-04-28T08:32:42+00:00 Office work and physical factors : health aspects of electromagnetic fields and light Sandström, Monica 1997 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-96906 eng eng UmeÃ¥ universitet, Yrkes- och miljömedicin National Institute for Working Life, UmeÃ¥, Sweden UmeÃ¥ : UmeÃ¥ universitet och Arbetslivsinstitutet UmeÃ¥ University medical dissertations, 0346-6612 530 http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-96906 urn:isbn:91-7191-386-6 info:eu-repo/semantics/openAccess Facial skin symptoms office illness electrical hypersensitivity physical environment flicker jitter neurophysiological effects Occupational Health and Environmental Health Arbetsmedicin och miljömedicin Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 1997 ftumeauniv 2024-04-09T23:38:33Z The overall aim of this thesis is to increase our knowledge of the physical environment of office workers with special focus on electromagnetic fields and to address the question of whether electromagnetic fields can directly or indirectly contribute to symptoms or discomfort among video display terminal ( VDT) workers. Furthermore, we have measured light modulation from various commonly used light sources in laboratory conditions and, as a second step, used modulated light as stimulus for provocation of neurophysiological responses in persons with perceived “electrical hypersensitivity†(EHS).During the last 20 years work-related illness among office workers has received increased attention. Changes in the physical environment, the introduction of VDTs and other electrical equipment and changes in light conditions have been discussed in this context. The basis for this thesis is the interdisciplinary Office Illness Project in Northern Sweden. Using a questionnaire completed by 4,943 office workers, 150 VDT workers with or without facial skin symptoms were selected for a case referent study of the electromagnetic fields in offices.When the measurements in the offices were performed in 1989, the general level of the 50 Hz magnetic fields in the offices was rather low, but in 5% of the offices the flux density exceeded 0.5 pT. At this level VDT monitors were shown to display detectable instability (jitter). Furthermore, the ability of test subjects (healthy volunteers) to detect jitter was shown to depend on both the amplitude and frequency characteristics of this instability. The study indicates that the instability of computer monitors and thereby the instability of the visual image of the VDT screen might be an increasing problem since it is known that the harmonic content of the general magnetic field in offices is on the rise.VDT monitors contributed to the magnetic field level at VDT workplaces in both extremely low and very low frequency ranges. However, the dominant source of electric fields in rooms ... Doctoral or Postdoctoral Thesis Northern Sweden Umeå University: Publications (DiVA) |
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Open Polar |
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Umeå University: Publications (DiVA) |
op_collection_id |
ftumeauniv |
language |
English |
topic |
Facial skin symptoms office illness electrical hypersensitivity physical environment flicker jitter neurophysiological effects Occupational Health and Environmental Health Arbetsmedicin och miljömedicin |
spellingShingle |
Facial skin symptoms office illness electrical hypersensitivity physical environment flicker jitter neurophysiological effects Occupational Health and Environmental Health Arbetsmedicin och miljömedicin Sandström, Monica Office work and physical factors : health aspects of electromagnetic fields and light |
topic_facet |
Facial skin symptoms office illness electrical hypersensitivity physical environment flicker jitter neurophysiological effects Occupational Health and Environmental Health Arbetsmedicin och miljömedicin |
description |
The overall aim of this thesis is to increase our knowledge of the physical environment of office workers with special focus on electromagnetic fields and to address the question of whether electromagnetic fields can directly or indirectly contribute to symptoms or discomfort among video display terminal ( VDT) workers. Furthermore, we have measured light modulation from various commonly used light sources in laboratory conditions and, as a second step, used modulated light as stimulus for provocation of neurophysiological responses in persons with perceived “electrical hypersensitivity†(EHS).During the last 20 years work-related illness among office workers has received increased attention. Changes in the physical environment, the introduction of VDTs and other electrical equipment and changes in light conditions have been discussed in this context. The basis for this thesis is the interdisciplinary Office Illness Project in Northern Sweden. Using a questionnaire completed by 4,943 office workers, 150 VDT workers with or without facial skin symptoms were selected for a case referent study of the electromagnetic fields in offices.When the measurements in the offices were performed in 1989, the general level of the 50 Hz magnetic fields in the offices was rather low, but in 5% of the offices the flux density exceeded 0.5 pT. At this level VDT monitors were shown to display detectable instability (jitter). Furthermore, the ability of test subjects (healthy volunteers) to detect jitter was shown to depend on both the amplitude and frequency characteristics of this instability. The study indicates that the instability of computer monitors and thereby the instability of the visual image of the VDT screen might be an increasing problem since it is known that the harmonic content of the general magnetic field in offices is on the rise.VDT monitors contributed to the magnetic field level at VDT workplaces in both extremely low and very low frequency ranges. However, the dominant source of electric fields in rooms ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Sandström, Monica |
author_facet |
Sandström, Monica |
author_sort |
Sandström, Monica |
title |
Office work and physical factors : health aspects of electromagnetic fields and light |
title_short |
Office work and physical factors : health aspects of electromagnetic fields and light |
title_full |
Office work and physical factors : health aspects of electromagnetic fields and light |
title_fullStr |
Office work and physical factors : health aspects of electromagnetic fields and light |
title_full_unstemmed |
Office work and physical factors : health aspects of electromagnetic fields and light |
title_sort |
office work and physical factors : health aspects of electromagnetic fields and light |
publisher |
Umeå universitet, Yrkes- och miljömedicin |
publishDate |
1997 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-96906 |
genre |
Northern Sweden |
genre_facet |
Northern Sweden |
op_relation |
Umeå University medical dissertations, 0346-6612 530 http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-96906 urn:isbn:91-7191-386-6 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1797589794471018496 |