The objective of this paper was to verify that problem of indoor air pollution is present in primary school in Yugoslavia. Indoor air pollutant levels of sulfur-dioxide, soot, nitrogen dioxide, carbon monoxide and formaldehyde, and air-microflora was determined in different places of school environment. The average indoor level of sulphur dioxide and soot in primary schools were comparatively high. Determined average levels of carbon monoxide were from 13 .2 - 31. 8 mg/m3, levels of nitrogen dioxide were 20 - 62 μg/m3 and levels of formaldehyde: 0.01 - 0.83 μg/m3.
An intervention study in eleven schools with approximately 1000 children age twelve to thirteen has been carried out in the period 1997 to 1999. Four schools with poor ventilation standard, three schools with carpets and four reference schools participated. In the schools with carpets, these have been removed and in the schools with poor ventilation systems, these have been upgraded to Norwegian standards for new buildings. A questionnaire was answered three times during a two-week period, asking how indoor environment-related symptoms were perceived.
The relationships between indoor environment and health, well being and ability to acquire knowledge are unquestionable. These are the reasons why in many countries a high level of indoor environment is required in school buildings. The goal of the paper is to compare the real state of the environment in classrooms in Poland with accepted requirements and standards. The evaluation of the existing situation is based on indoor environment measurements in 28 classrooms in Warsaw.
In this study, we investigated the indoor air quality (IAQ) in classrooms with exhaustventilation systems and in naturally ventilated classrooms. In the latter, we found peak CO2-concentrations of more than 4000 ppm. 1500 ppm was exceeded during 40 to 86% ofteaching time, dependent on class size. The windows were opened rarely in winter which ledto low mean air exchange rates of 0.20 0.23 h^-1. The operation of mechanical ventilationsystems improved IAQ considerably. Peak CO2-concentrations decreased to less than 2500ppm. 1500 ppm was exceeded for only 7 to 57% of teaching time.
The paper presents a ventilation comfort chart that has been developed under Thailand climate and using Thai volunteers. 183 male and 105 female college-age subjects were exposed to different thermal conditions in order to investigate the effect of air velocity on thermal comfort in ventilated "non-conditioned" spaces. To this end commercial electric fans were used to control the air velocity near the subjects. The air velocity varied between 0.2 and 3 m/s. Room conditions varied between 26°C and 36°C (D.B.T.) and 50-80% relative humidity.