An experimental study on effects of increased ventilation flow on students' perception of indoor environment in computer classrooms.
2008 (English)In: Indoor Air, ISSN 0905-6947, Vol. 18, no 4, 293-300 p.Article in journal (Refereed) Published
The effects of ventilation in computer classrooms were studied with university students (n = 355) in a blinded study, 31% were women and 3.8% had asthma. Two classrooms had a higher air exchange (4.1-5.2 ac/h), two others had a lower air exchange (2.3-2.6 ac/h). After 1 week, ventilation conditions were shifted. The students reported environmental perceptions during the last hour. Room temperature, RH, CO2, PM10 and ultra-fine particles were measured simultaneously. Mean CO2 was 1185 ppm at lower and 922 ppm at higher air exchange. Mean temperature was 23.2 degrees C at lower and 22.1 degrees C at higher air exchange. After mutual adjustment (temperature, RH, CO2, air exchange), measured temperature was associated with a perception of higher temperature (P < , 0.001), lower air movement (P < , 0.001), and poorer air quality (P < , 0.001). Higher air exchange was associated with a perception of lower temperature (P < , 0.001), higher air movement (P = 0.001), and better air quality (P < , 0.001). In the longitudinal analysis (n = 83), increased air exchange caused a perception of lower temperature (P = 0.002), higher air movement (P < , 0.001), better air quality (P = 0.001), and less odor (P = 0.02). In conclusion, computer classrooms have CO2 levels above 1000 ppm and temperatures above 22 degrees C. Increased ventilation from 7 l/s per person to 10-13 l/s per person can improve thermal comfort and air quality.
Place, publisher, year, edition, pages
2008. Vol. 18, no 4, 293-300 p.
carbon dioxide, indoor air quality, ventilation, room temperature; perceived air quality, computer classrooms, university students
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-17180DOI: 10.1111/j.1600-0668.2008.00530.xISI: 000257779200005PubMedID: 18422569OAI: oai:DiVA.org:uu-17180DiVA: diva2:44951