- providing an adequate amount of outdoor air on a continuous basis;
- controlling humidity in the space so that it is usually between 30% and 60% rh; and
- providing a level of particulate filtration efficiency for outdoor air adequate to prohibit most mold spores and fungi from entering the hvac system.
Study Finds IAQ Problems Common in U.S. Schools
August 3, 2000
U.S. government studies have shown that one in five schools has indoor air quality (IAQ) problems, but such problems can be improved through use of active humidity control and continuous ventilation, according to new research. More than 8 million students are affected by problems with IAQ, according to U. S. government research outlined in an article published in IAQ Applicationsby the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Problems can include drowsiness, lack of concentration, or headaches, which affect comprehension and motivation of students. Researcher Charlene Bayer, Ph.D., Georgia Tech Research Institute, said IAQ should be a top priority in schools because children, who are still developing physically, are more likely to suffer due to indoor pollutants. Also, the number of children with asthma has increased 49% since 1982. Researchers are studying the impact of continuous ventilation (where the system runs 24 hours a day) and active humidity control on IAQ in schools. Problems with IAQ may stem from school personnel not understanding how to operate ventilation systems and introducing contaminants, such as plug-in chemical deodorizers and art supplies, into classrooms. Bayer said use of active humidity control and continuous ventilation can help improve problems with IAQ. Research showed that pollutant levels dropped when higher outdoor air was delivered. Based on a study of existing IAQ research, Bayer and her co-authors suggest that most IAQ problems in schools can be avoided by: