This study was performed to investigate the characteristics of asbestos distribution in 6 public and 6 school buildings from August to September in 2006. The bulk samples were analysed by PLM(polarized light microscope). Also the airborne samples were analysed PCM(phase contrast microscope) and confirmed by SEM-EDX(scanning electron microscope-energy dispersive using X-ray analysis) method. The 6 public buildings included the ACM(asbestos containing material) ranged 2-7 % of chrysotile in 70 % of samples from ceiling, floor tile, and wall board and has 20 % tremolite in 2 ceiling plaster. The 6 school buildings were identified 1.5 % tremolite in one sample and showed the similar asbestos distribution with the public building. The airborne concentrations of fiber materials were ranged with 0.000-0.017 f/cc in public places and 0.000-0.012 f/cc in school building by PCM. However, the asbestos fibers could not be found by SEM-EDX. In the result of physical assessment of ACM in each buildings, it is considered that there is no chance of a hazardous situation because the ACM is not friable. Its suggested that the asbestos control plan should be established to prevent asbestos exposure to occupants from damaged ACM by repairing and custodial work.
This study was performed to investigate the concentration levels of CO2 and the associated parameters in the subway from lines 1 to 8 in Seoul metropolitan area, during 1 to 30 Sept. 2005. CO2 concentration was measured at the entrance and center in subway passenger cabin by non-dispersive infrared analyser. The associated parameters for CO2 were estimated based on the number of passenger, open and closed doors etc. The mean CO2 concentrations were measured to be 1,646±712 ppm in subway passenger cabins. The CO2 concentrations showed the highest values between 7 and 9 AM in rush hour(p〈0.01). The correlation coefficient between CO2 and the number of passenger was highly significant(r=0.824). The general linear model indicated that subway line, subway location (ground and underground tract), and measurement point (enterance and center of cabins) and running time (morning and afternoon) significantly influenced the concentrations of CO2. An extended study is needed to examine the sources of CO2 in subway cabins and to compare pollutants concentration among subway lines.