To research indoor air pollution in the training rooms of technical high school, the temperature, air current, humidity, CO2, CO, O3 were measured by Indoor Climate System(ICS 500, Casella, UK) at each classroom, scientific laboratory, electricity training room, electronic equipment training room and welding training room. The change of air pollution concentration and its correlation were additionally compared and analyzed. At closed small space such as classroom, scientific laboratory, electronic equipment training room and electricity training room, the CO2 concentration was obtained to the 2,030ppm(max.), which is higher than notified and recommended standard value(1,000ppm) by Ministry of Health and Welfare and Ministry of Environment, Korea. At welding training room where is larger and more ventilated than general classroom, CO concentration was measured to the 3.6ppm, which is higher than average 1ppm measured at other training rooms. The concentration of O3 is not yet regulated from the standards of underground air quality, but at welding training room it was measured as 0.11ppm(max.) that is higher than 0.01ppm measured at other training rooms. The higher value of temperature, air current, radiant temperature and CO2 concentration was shown at scientific laboratory, electricity training room and electronic equipment training room where are closed and same with the scale of classroom. And the higher concentration of CO2, CO and O3 was shown at welding training room which was opened larger classroom. The indoor air pollution by CO2, CO and O3 may directly affect on the training room where many students work at a small space, and they should be controlled appropriately. Each experimental formulas were made for the estimation of CO2, CO and O3 concentration depending on some kinds of variables at each training room. It is found that indirect ventilation system with a filter will be needed for regular and constant ventilation and the ventilation system should be applied to protect and make clean and comfortable environment of training rooms at technical high school.
To examine the fluctuations of aerosol number concentration with different size in the boundary layer of marine area during summer season, aerosol particles were assayed in the Ieodo Ocean Research Station, which is located 419 km southwest of Marado, the southernmost island of Korea, from 24 June to 4 July, 2008. The Laser Particle Counter (LPC) was used to measure the size of aerosol particles and NCEP/NCAR reanalysis data and sounding data were used to analyze the synoptic condition. The distribution of aerosol number concentration had a large variation from bigger particles more than 3 μm in diameter to smaller particles more than 1 μm in diameter with wind direction during precipitation. The aerosol number concentration decreased with increasing temperature. An increase (decrease) of small size of aerosol (0.3∼0.5 μm in diameter) number concentration was induced by convergence (divergence) of the wind fields. The aerosol number concentration of bigger size more than 3 μm in diameter after precipitation was removed as much as 89∼94% compared with aerosol number concentration before precipitation. It is considered that the larger aerosol particles would be more efficient for scavenging at marine boundary layer. In addition, the aerosol number concentration with divergence and convergence could be related with the occurrence and mechanism of aerosol in marine boundary layer.
To understand the development mechanism of the aerosols in the surface boundary layer, the variation in the aerosol number concentration due to the divergence and convergence of the wind fields was investigated. The aerosol number concentration was measured in the size ranges of 0.3∼10.0 ㎛ using a laser particle counter(LPC) from 0000 LST on 03 Feb. to 0600 LST on 07 Feb. 2004 at Mokpo in Korea during snowfall. The Velocity Azimuth Display(VAD) technique was used to retrieve the radar wind fields such as the horizontal wind field, divergence, and deformations including the vertical air velocity from a single Doppler radar. As a result, the distribution of the aerosol number concentration is apparently different for particles larger than 1 ㎛ during snowfall, and it has a tendency to increase at the beginning of the snowfall. The increase and decrease in the aerosol concentration due to the convergence and divergence of the wind fields corresponded to the particles with diameters greater than 1 ㎛. It is found that the fluctuations in the aerosol number concentration are well correlated with the development and dissipation of snowfall radar echoes due to the convergence and divergence of horizontal wind fields near the surface boundary layer in the inland during the snowfall.