Abstract:

Objective To evaluate the bactericidal effect of a new type of medical air disinfector (short for new air disinfector) using a new angular column-shaped photocatalyst system under the condition of man-machine co-existing environment, and to study the improvement of killing pathogenic microorganisms in the air. In particular, the air disinfection technique and method of killing Mycobacterium tuberculosis (Mycobacterium bovis BCG strain (short for BCG)) was used in this experiment.Methods A new air disinfector was used to sterilize the natural bacteria in the air in a 47m ³ laboratory room. The test was repeated three times, and the extinction rate was calculated separately each time. In two adjacent aerosol chambers with volume of 30m ³ (one for experimental control, for calculating the natural extinction rate of bacteria, one for disinfection test, for calculating the killing rate of bacteria), the bactericidal test was conducted to sterilize Staphylococcus albus and BCG in air. The experiment was repeated three times, and the natural extinction rate and killing rate were calculated respectively. The number of colonies in the air in the aerosol room of Staphylococcus albus and BCG after sterilization test should be from 1×10 ⁵CFU/m ³ to 5×10 ⁵CFU/m ³ and from 3×10 ⁴CFU/m ³ to 8×10 ⁴CFU/m ³. Results Air simulated field disinfection test using a new type of air disinfector was carried out disinfection test of Staphylococcus albus in air field with repeated three times. The natural extinction rates of Staphylococcus albus in air were 20.45%,20.00% and 20.36%, respectively. The bactericidal rates of three repeated disinfection tests were 99.97%, 99.96% and 99.95%, respectively. With three repeated tests on disinfection of natural bacteria in air field, the extinction rates of natural bacteria in air were 93.95%, 94.27% and 94.32%, respectively. With three repeated tests on disinfection of natural bacteria in air field, the natural extinction rates of BCG in air were 35.71%, 37.93% and 40.58% respectively. The bactericidal rates of three repeated disinfection tests were 99.67%, 99.61% and 99.73%, respectively.Conclusion Pathogenic microorganismcan and MTB in air environment could be killed strongly using a new type of medical air disinfector with angular column-shaped photocatalyst system.

Key words: Mycobacterium tuberculosis, Disinfection, Decontamination, Toilet facilities, Air microbiology, Evaluation studies