Objective To compare the dynamic disinfection effect of upper-room ultraviolet irradiation at 222 nm and 254 nm on the air in different areas of the bronchoscopy room of a tertiary first-class infectious disease hospital, and provide new insights for air disinfection in specialized diagnosis and treatment areas of medical institutions. Methods The treatment room and cleaning room of the bronchoscopy room of a tertiary first-class infectious disease hospital were selected. The upper-room ultraviolet irradiation air disinfectors of 254 nm (as control group) and 222 nm (as test group) were installed at a height of 2.6 meters above the ground in the first and the second working weeks, respectively. Difference in total bacterial colonies in the air between two groups was compared. Results The average bacterial colonies in the air of cleaning room and treatment room of bronchoscopy room in the test group were both lower than those of the control group (both P<0.05), and maintained a low level throughout the entire period. The qualified rates of dynamic air bacterial colonies in both the control group and the test group were 100%. The time percentage that the control group met the class I environmental level was 87.5%, while that of the test group was 100%. Conclusion The upper-room ultraviolet irradiation at 222 nm is more effective in improving the qualified rate of dynamic air bacterial colonies and enhancing the environment of the bronchoscopy room compared with upper-room ultraviolet irradiation at 254 nm, and continuous irradiation helps to maintain air safety and cleanliness.