@article{oai:repository.lib.tottori-u.ac.jp:00005027,
 author = {Houri, Daisuke and Houri, Daisuke and Kanazawa, Yousuke and Morioka, Ikuharu and Matsumoto, Kenji and Matsumoto, Kenji and Kanazawa, Yousuke and Morioka, Ikuharu},
 issue = {2},
 journal = {Yonago Acta medica, Yonago Acta medica},
 month = {Jun},
 note = {To make clear the realities of indoor air (IA) pollution in lecture rooms of Tottori University in Japan, we studied air quality by monitoring the CO2 level, an index of IA pollution. We changed IA environment of lecture rooms while the lecture was given by using fan-ventilation or not, and with room doors open or closed: we monitored the CO2 level at 5-min intervals during 2 or 3 consecutive 90-min lectures using an infrared ray absorption type CO2 monitor. Based on the observed levels for 90 min, we calculated the ventilation rate (times of operating the ventilation fan), and estimated CO2 level change in ventilated and non-ventilated rooms for a 90-min lecture with the ventilation rate. In non-ventilated rooms, the observed and estimated CO2 level exceeded the maximum of 1,500 ppm specified by the Japanese Government. The excess was irrespective of the ratio of air volume/ person in non-ventilated rooms with doors closed. During the 1-h lunch break with doors open, over 5,000 ppm levels dropped below the standard. During the lecture in fan-ventilation, the CO2 level was decreased to below or near above the standard. Fan-ventilation during the lecture break reduced the level nearly to that in the outside air. In the case of no fan-ventilation during the following lecture(s), the level exceeded the standard. To maintain a clean air environment in highly airtight university lecture rooms, ventilation during lectures was crucial, which can be done effectively by the use of ventilation fans. Use of the estimated level is generally adaptive in promoting the use of ventilation fans.},
 pages = {77--84},
 title = {Indoor Air Quality of Tottori University Lecture Rooms and Measures for Decreasing Carbon Dioxide Concentrations},
 volume = {52},
 year = {2009}
}