Improving medical waste treatment in the Republic of Korea through diversification of operating conditions in sterilization and crushing facilities

This study aims to evaluate the biological safety of steam sterilization and crushing facilities under different operating conditions by assessing sterilization efficacy and the operational environment, and to propose strategies for expanding facility installation through diversification of treatment conditions. Sterilization tests were conducted at a currently operating steam sterilization and crushing facility in the Republic of Korea under both the current legal condition (121℃ / 30 min / 1 bar gauge(1 atm gauge)) and an optimal treatment condition (138 ℃ / 10 min / 2.5 bar gauge(3.5 atm absolute)), using five microbial species recommended by the WHO. Under both conditions, four microbial species exhibited a 99.9999% inactivation rate, and no fungi were detected. These results satisfied Level 3 of the WHO's four-level inactivation standard for medical waste treatment. To confirm the operational safety of the facility, the pH of the wastewater generated during the process was measured, and the average value was 7.59. The moisture content of the sterilized and crushed waste was 38.1% under the legal condition and 26.5% under the optimal condition, meeting the legal standard of below 50%. Analysis of indoor air quality before and after facility operation showed that concentrations of PM10, PM2.5, formaldehyde, and total airborne bacteria remained similar, while the concentration of total VOCs increased after operation. Based on these results, this study proposes a measure to install more facilities by diversifying interim treatment methods, in consideration of the conditions currently stipulated by the Wastes Control Act in the Republic of Korea, and the possibility of introducing technologically advanced equipment in the future.