امكان سنجي كاربرد سيستم پرتوتابي ميكروب كشي فرابنفش در غير فعال سازي ميكروارگانيزم هاي موجود در هوا

Feasibility study on the use of Ultra Violet Germicidal Irradiation (UVGI) system in inactivation of indoor air

Introduction: Contamination of indoor air by microbial pollutants such as fungi, bacteria and viruses has been increasingly recognized as a public health problem and may be responsible for building-related illness (BRI) and sick building syndrome (SBS). Up to now, the different methods have been applied for killing/inactivation microbial pollutants in indoor air. One of the new methods is "UVGI system. This stydy presents the feasibility of UVGI system in inactivation of air born pathogens. Methods: For this purpose a stand-alone UVGI unit has been used. The characteristics of the studied system are as fallows: radiation 11.2 W, contact time 0.6 S, airflow rate 30 m3/h. Heterotrophic plate count (HPC), ozone, air flow rate and temperature were selected as the most decisive healthy and technological parameters for a practical application. All of the parameters were examined in accordance with the standard methods. Results: This study showed that, this system can inactivate/kill 92.5 percent of microorganisms in passing air flow through the system. Average air temperature in outlet of system was 10 centigrade degree warmer than inlet air. Also, Ozone concentration in samples taken from inlet and outlet of reactor was under detection limit. Conclusion: Based on observed results, the use of tested system in practice seems to be a potential technology for indoor air disinfection without ozone production as a bye product.