No abstract

The ventilation performance of airborne infection isolation rooms (AIIRs) was assessed in three Finnish hospitals by examining the air change rate, contaminant removal efficiency and leakage of contaminants outside the isolation room by using tracer gas techniques. Results showed that infectious agents can escape from the AIIR during egress despite high ventilation rates in the AIIR and anteroom (air change rate, 4–24 h−1) and the pressure difference between the AIIR and corridor was −0.2 to −29 Pa. The control of impurities was often ineffective due to inappropriate direction of air flows and air moving from the patient towards the health care worker and anteroom. Although an anteroom reduces leakage of infectious agents to the corridor significantly, it does not prevent this completely when healthcare workers move between the AIIR and corridor. To enhance the protection of AIIRs, it is especially important to pay attention to the air distribution and removal efficiency of impurities in AIIRs and anterooms. Performance of AIIRs should be tested regularly, especially among older AIIRs.

The study examined the extent and prevalence of perceived indoor environment-related (IE-related) symptoms environmental complaints and psychosocial work environmental factors in Finnish office, school and health care environments. Material and Methods: The data were collected from non-industrial workplaces (N = 455) in 2011-2012 and 2015-2017 using the Finnish Institute of Occupational Health's Indoor Air Questionnaire (IA Questionnaire). Suspicion of IE-related problems was reported in 59% of workplaces. The data consisted of 28 826 employees' responses. Results: The employees reported symptoms and environmental discomfort in office environments less often than in school or health care environments. The most often reported IE-related complaints were stuffy air (39% of respondents), dry air (34%) and insufficient ventilation (33%). The most often reported symptoms were irritation of the nose (27% of respondents), irritation of the eyes (26%), and hoarse or dry throat (24%). The results showed differences between the perceived IE in office, school and health care environments. Conclusions: Compared to earlier findings, the most often perceived IE-related symptoms and complaints have increased in Finnish health care environments. The office employees' perceptions of psychosocial work environment remained fairly unchanged whereas health care personnel more often assessed their psychosocial environment as positive compared to previous reports. Instead of exact reference values, comparing the results of IA Questionnaires with the distributions and mean values of the results of this study may be more informative for those striving to solve IE-related problems. The presented distribution and mean values of perceived symptoms, environmental complaints and psychosocial work environment might help to relate the results to other workplaces. This, in turn, might increase the understanding that IA Questionnaire results are influenced by many factors. The results presented can be used as new reference material when interpreting the results of IA Questionnaires in office, school and health care environments.

Objectives: Airborne particle concentrations can be used as quality indicators of indoor environments. The previous lack of reference data has limited the use of particle measurements in office environments. The aim of this study was to describe the concentrations of airborne particles (≥ 0.5 μm and ≥ 5.0 μm) in 122 Finnish office buildings with suspected indoor air problems. Materials and Methods: The database consisted of indoor air and supply air particle samples collected in 2001-2006 from the Helsinki area. The particle concentrations (≥ 0.5 μm and ≥ 5.0 μm) were measured in the indoor air (528 samples from 122 office rooms) and in the supply air (384 samples from 105 office rooms) with an optical particle counter. Airborne particle concentrations ≥ 0.5 μm were categorized according to the efficiency of supply air filtration and health survey data. Results: The mean concentrations in the indoor air equaled 1900 particles/l and in the supply air 1300 particles/l. The efficiency of supply air filtration decreased the fine particles counts in both the indoor and supply air. The counts of large particles, ≥ 5.0 μm, were low in the indoor air. Airborne counts of ≥ 0.5 μm particles (geometric mean) were statistically higher in the offices whose occupants had work-related symptoms (eye and/or upper respiratory symptoms or upper respiratory infections) than in the offices whose occupants had no such symptoms. However, the symptoms may also be linked to other indoor air problems or particle characteristics not studied in this work. Conclusions: This study indicates typical airborne particle levels (≥ 0.5 μm and ≥ 5.0 μm) in Finnish office buildings with suspected indoor air problems. The results can be used to evaluate the quality of indoor environment, possible indoor air problems, and the need for additional investigations.

The present report describes exposure to respirable silica and dust in the construction industry, as well as means to manage them. The average exposure in studied work tasks (n = 148) amounted to 64% of the Finnish OEL value of 0.05 mg/m3. While 10% of exposure estimates exceeded the OEL, the 60% percentile was well below 10% of the OEL, as was the median exposure. In other words, exposure was low in more than half of the tasks. Work tasks where exposure was low included construction cleaning, work management, installation of concrete elements, rebar laying, driving work machines equipped with cabin air intake filtration, and landscaping, in addition to some road construction tasks. Excessive exposure (>OEL) was related to not using respiratory protection at all or not using it for long enough after the dusty activity ceased. Excessive exposures were found in sandblasting, dismantling facade elements, diamond drilling, drilling hollow-core slabs, drilling with a drilling rig, priming of explosives, tiling, use of cabinless earthmoving machines, and jackhammering, regardless of whether the hammering took place in an underpressurized compartment or not. Even in these tasks, it was possible to perform the work safely, following good dust prevention measures and, when necessary, using respiratory protection suitable for the job. Furthermore, in all tasks with generally low exposure, one could be significantly exposed through the general air or by making poor choices in terms of dust control.