Ozone has become a significant pollutant not only outdoors but also indoors. The ozone emission test was conducted for the sum of forty five air cleaners selected in the online shops and department stores. Negative ion emission test was also conducted for the selected fifteen ones which had the function to generate negative ions. Filter-type and complex type air cleaners emitted ozone less than 0.05 ppm, the standard of indoor ozone emission of air cleaner. Wet type ones emitted no ozone. In the case of ionizer type, 66.7% in the nine ones emitted ozone about 1.4~10 times larger than 0.05ppm. Most of air cleaners used a pin corona discharge emitted large amount of ozone. Those which used carbon fiber emitted little ozone in spite of generating a lot of negative ions.

This study analyzes the effect of negative air ions on the concentration of airborne particulate matter and evaluates the expected purification efficiency of open spaces for particulate matter by investigating the amount of negative air ions generated by plants. This study establishes a negative air ion generation treatment environment, plant environment, and control environment to measure the purification efficiency of particulate matter under the conditions of each, analyzing the expected purification efficiency by designing a particulate matter purification model. Results show that the amount of generated negative air ion according to environment was negative air ion generation treatment environment > plant environment > control environment; this order also applies to the particulate matter purification efficiency. Moreover, it took 65 min for the negative ion generation treatment environment, 90 min for the plant environment, and 240 min for the control environment to reach the standard expected purification efficiency of particulate matter concentration of 960 mg/m³ for PM10. For PM2.5, with the designated maximum concentration of 700 mg/m³, it took 60 min for the negative ion generation treatment environment, 80 min for the plant environment, and more than 240 min for the control environment. Based on these results, the expected purification efficiency compared to the control environment was quadrupled in the negative ion generation treatment environment and tripled in the plant environment on average.

This study analyzed the placement shape and correlation of green space focusing on anion that is one of curing substances. As its result, it was found out that the meteorological element becomes different and the generated amount of anion also gets different along such different meteorological element in case the shape of placing green space. As the result of analyzing the correlation with meteorological element , it was analyzed that it was the positive correlation in case of time, temperature and relative humidity and it was also analyzed that it was negative correlation in case of wind velocity and amount of light. But, in case of wind velocity, it was considered that the further complement research is required as the sampling distribution was shown as so biased by the windproof effect of the trees planted at the outskirts of green space in case of wind velocity. Based on th analyzed results as above, it suggested the model of generating anion by implementing multiple regression analysis such as y = -2462.383 + 0.304x1 x 72.746x2 x 7.315x3 x - 0.138x4 (x1; time, x2; air temperature, x3; relative humidity, x4; luminous intensity, R2; 0.691).