Effects of pollution from personal computers on perceived air quality, SBS symptoms and productivity in offices.

UNLABELLED In groups of six, 30 female subjects were exposed for 4.8 h in a low-polluting office to each of two conditions--the presence or absence of 3-month-old 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 low-polluting 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, 2-ethylhexanol, 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, so-called '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-month-old PC would need to be increased several times to achieve the same perceived air quality as in a low-polluting 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 PC-generated air pollutants could be reduced by modifications in the manufacturing process, increased ventilation, localized PC exhaust, or personalized ventilation systems.

[1]  T. Reynolds.  Contamination of PC-SPES remains a mystery. , 2002, Journal of the National Cancer Institute.

[2]  P Wargocki,et al.  Subjective perceptions, symptom intensity and performance: a comparison of two independent studies, both changing similarly the pollution load in an office. , 2002, Indoor air.

[3]  A Aarås,et al.  Musculoskeletal, visual and psychosocial stress in VDU operators before and after multidisciplinary ergonomic interventions. A 6 years prospective study--Part II. , 2001, Applied ergonomics.

[4]  Peder Wolkoff,et al.  Organic compounds in indoor air—their relevance for perceived indoor air quality? , 2001 .

[5]  A. Bergman,et al.  Flame retardants in indoor air at an electronics recycling plant and at other work environments. , 2001, Environmental science & technology.

[6]  Maxwell T. Fogleman,et al.  Effectiveness of a VDT ergonomics training program , 2001 .

[7]  P. Fanger,et al.  The effects of outdoor air supply rate in an office on perceived air quality, sick building syndrome (SBS) symptoms and productivity. , 2000, Indoor air.

[8]  C J Weschler,et al.  Ozone in indoor environments: concentration and chemistry. , 2000, Indoor air.

[9]  R. Burgess-Limerick,et al.  The prevalence of neck and upper extremity musculoskeletal symptoms in computer mouse users , 2000 .

[10]  Håkan Carlsson,et al.  Video Display Units: An Emission Source of the Contact Allergenic Flame Retardant Triphenyl Phosphate in the Indoor Environment , 2000 .

[11]  P Wargocki,et al.  Perceived air quality, sick building syndrome (SBS) symptoms and productivity in an office with two different pollution loads. , 1999, Indoor air.

[12]  J. McCann,et al.  The genotoxic potential of electric and magnetic fields: an update. , 1998, Mutation research.

[13]  C. Weschler,et al.  Potential reactions among indoor pollutants , 1997 .

[14]  Per Axel Clausen,et al.  Are We Measuring the Relevant Indoor Pollutants , 1997 .

[15]  C S Pan,et al.  The impact of keyboard design on comfort and productivity in a text-entry task. , 1997, Applied ergonomics.

[16]  K. Prync-Skotniczny,et al.  Subjective fatigue symptoms among computer systems operators in Poland , 1996 .

[17]  Jan Sundell,et al.  Sick Building Syndrome (SBS) in Office Workers and Facial Skin Symptoms among VDT‐Workers in Relation to Building and Room Characteristics: Two Case‐Referent Studies , 1994 .

[18]  U O Bergqvist,et al.  Eye discomfort and work with visual display terminals. , 1994, Scandinavian journal of work, environment & health.

[19]  P. Fanger.  Introduction of the olf and the decipol units to quantify air pollution perceived by humans indoors and outdoors , 1988 .

[20]  B. Knave,et al.  Work with video display terminals among office employees. I. Subjective symptoms and discomfort. , 1985, Scandinavian journal of work, environment & health.

[21]  J. Myers,et al.  Influences on sick building syndrome symptoms in three buildings. , 1995, Social science & medicine.