English

Examines the effect of a new, individually controlled ventilation system on employee symptoms. Two groups of employees were studied in one office building with mechanical ventilation, with one group the control. Individual control of the workspace ventilation was given to the intervention group. The new system gave higher air velocities, more variable temperatures, and higher concentration of airborne dust and fungal spores. Nevertheless, after four months, employees reported fewer symptoms.

The outdoor air supply was manipulated over a period of six week in two mechanically ventilated offices in Montreal, and symptoms and environmental parameters noted. Higher dust and higher nitrogen dioxide concentrations led to eye symptoms reports. Higher TVOCs were associated with mucosal symptoms. Higher dust levels were associated with systemic symptoms.

A newly built nursing home was analysed to establish why there had been a significantly lower attack rate in this building during a type A influenza epidemic. Measurements were taken of the number of respiratory illnesses and influenza cultures in consenting symptomatic residents, and of building characteristics. Of the four buildings in the home, Building A had significantly fewer culture-confirmed cases than the other buildings. Building A's ventilation system was unique, it had more public space per resident, and did not have office space serving the whole complex.

A group of 638 children was studied at 3 and 18 months to assess the development of symptoms possibly related to allergy or other types of hypersensitivity. Logistic regression techniques were used in the analysis. Where there was a high incidence of investigated symptoms, a family history of atopy was linked. Day nursery attendance was associated with increased risk of colds and treatment with antibiotics. Coughing was worse in homes with smoking mothers. Risk of symptoms increased with the presence of a sibling. Building factors were not significant.

Environmental conditions, sick building syndrome symptoms, job satisfaction, job stress, and occupational and personal information were assess by questionnaire of 4479 employees from 27 air conditioned offices, and indoor air quality measurements taken. IAQ met the ASHRAE guidelines for all the buildings. Found that the number of sick building syndrome symptoms per employee was linked linearly to computer use, job stress, job satisfaction, number of allergies, migraine and eye wear.

Describes the California Healthy Building Study, which attempted to assess the relationship between ventilation system type and employee symptoms. Three naturally ventilated, three mechanically ventilated and six air conditioned buildings were studied. Higher adjusted prevalences of most symptom outcomes were linked with both mechanical and air conditioned ventilation.

Regression techniques were used to assess the associations between environmental factors and work-related health conditions. The study used environmental and health data for 2435 persons in 80 offices. When adjusted for age and gender, relative risks for multiple lower respiratory symptoms were increased for variables in the HVAC design and maintenance categories, with the highest for presence of debris inside the air intake, and for poor or no drainage from drain pans. Multiple atopic symptoms were related to suspended ceiling panels. Asthma was related to renovation with new drywall.

Describes a study carried out one year before and one year after a move from a naturally ventilated building to an artificially ventilated one by 167 clerical workers. The study examined the influences of physical and psychosocial work environments and personal factors on sick building syndrome symptoms. Female gender and VDU work were linked to most symptoms in both surveys. There was a significant increase after the move in eye, skin and fatigue symptoms.

Describes a cross sectional study carried out on 2678 employees in 41 office buildings in March 1991 aimed at examining the role of sick building syndrome symptoms. Concludes that the risk of the studied symptoms is related to the type of ventilation in the existing office building stock. Suggests that future studies should concentrate on the typical function problems and specific causes connected with the high-risk ventilation systems.

Attempts to examine the relationship between ventilation rate and sick building syndrome symptoms. Uses a cross sectional population based study of 399 workers in 14 mechanically ventilated office buildings without air recirculation or humidification in Finland. Air flow was measured through exhaust air outlets in the room. A questionnaire was also used. States that the results suggest that outdoor air ventilation rates below the optimal increase the risk of sick building syndrome symptoms.