Indoor Air Quality Assessment of Daycare Facilities with Carbon Dioxide Temperature, and Humidity as Indicators. (Features)
Ferng, Shiaw-Fen, Lee, Li-Wen, Journal of Environmental Health
Today, over 50 percent of mothers whose youngest children are under the age of six are in the workplace (Hofferth & Phillips, 1987; Strauman-Raymond, Lie, & Kempf-Berkesth, 1993). A large number of American children are being taken care of inside daycare settings. Research studies indicate, however, that child daycare service environments can be hazardous places for young children because of indoor air quality (IAQ) problems (Daneault, Beausoleil, & Messing, 1992). Since young children differ from older age groups in terms of physical structures and functioning--their lungs are still developing, as are their immune and central nervous systems, and they have higher respiratory rates and rates of physical activity--they are more vulnerable to indoor air pollutants (Miller, 1993). Thus, appropriate indoor environment in daycare centers and homes has become a public focus.
It has been found that ventilation is inadequate in many daycare services, especially those built in the 1970s (Gursky, 1991). Research also has shown that daycare providers are aware of the IAQ issues in their facilities but that many have decided not to address the issue because they believe assessing and correcting IAQ problems is not their responsibility (LaFollette, Hobson, & Crank, 2000). These results alert us to potential problems that may adversely affect the health of many young children.
The commonly seen indoor air pollutants are gases and vapors such as carbon monoxide (GO), carbon dioxide ([CO.sub.2]), formaldehyde (HCHO), other volatile organic compounds (VOCs), and oxides of nitrogen (NO and [NO.sub.2]), as well as radon, particles from biological aerosols (fungi, mold spores, pollen, insect parts, and feces), asbestos fiber, and tobacco smoke. Excessive [CO.sub.2] exposure can cause headaches, tiredness, and decrease in mental acuteness, and it increases the risk of sudden infant death (Corbyn, 1992). Studies also have demonstrated that the relationship between [CO.sub.2] concentrations and IAQ evaluation is relatively distinct (Rajhans, 1985; Yocom & McCarthy, 1991; Daneault et al., 1992; Olesen & Seelen, 1993; Haghighat & Donnini, 1993). American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) standard sets 2,500 parts per million (ppm) as the upper limit for indoor [CO.sub.2] concentration, but 1,000 ppm is the recommended maximum. Temperature and relative humidity were also used to determine the comfort level of the indoor environment at daycare facilities (ASHRAE, 1989).
Concerned about the IAQ young children are exposed to, the authors of this study evaluated the current IAQ status of licensed daycare facilities in a Midwestern county of the United States.
Selection of Participants
Participants were randomly selected from a total of 122 licensed daycare centers and homes listed in a Midwestern county of the United States. A letter explaining the purpose of the study was sent to the providers of the selected daycare centers and homes requesting their participation. A follow-up phone call was made if they did not respond to the first request. A total of 26 daycare providers agreed to participate in the study. The participants comprised 16 daycare centers and 10 daycare homes. The overall participation rate was 21.3 percent; response rates from daycare centers and homes were 94.1 percent and 9.5 percent, respectively A daycare home is defined as a private dwelling for the care of children under 11 years of age. A daycare center is defined as any institution designed for the purpose of providing care or maintenance for children less than six years of age (Indiana State Department of Public Welfare, 1992).
Indoor Air Quality Measurement
[CO.sub.2] concentration, temperature, and relative humidity are commonly used as indicators of indoor air quality and comfort level because they are convenient and reliable (Daneault et al. …