What are the factors that affect the effect of ultraviolet sterilization?

Ultraviolet sterilization effect is strong, can be widely used in the operating room, burn ward, infection ward and sterile space disinfection and not heat resistant articles and table surface disinfection as well as some packaged food disinfection. The commercial ultraviolet sterilization machine is a very widely used home sterilization equipment. So in the use of ultraviolet sterilization work, what are the influence factors?

Major influencing factors of using UV sterilizing

1. Type, quality and reflective cover of ultraviolet lamp tube

It has been reported that different species of bacteria were irradiated by high boron ultraviolet lamp and quartz ultraviolet lamp respectively. The results showed that the number of bacteria surviving under the ultraviolet lamp of quartz glass tube was less, while the number of bacteria surviving under the ultraviolet lamp of high boron glass tube was more. Therefore, the ultraviolet lamp of quartz glass tube was better.

The quality of ultraviolet lamp tube can not be based on old and new, whether to produce blue light, whether to form ozone to make a judgment, must detect its intensity.

2. Lamp tube cleanliness

Experiments show that the lamp tube if there is dust cover, because the ultraviolet penetration is very weak, dust can reduce its intensity. After wiping with anhydrous alcohol, the output intensity increased by 6.29 W/cm2 on average. Accordingly, ultraviolet lamp tube should keep clean in use process.

3. Germicidal distance and duration

Theoretically, the effective distance of ultraviolet sterilization of the UV sterilizer machine is within 2m. Some studies have reported that the closer the irradiation distance is, the better the sterilization effect is.

That is, the distance is inversely proportional to the effect. With the known staphylococcus aureus, the number of viable bacteria was 7 at 1m away from the uv lamp for 30min, and the number of viable bacteria was 30 at 2m.

4. Different biological times

Some people on ultraviolet sterilization experiment research found that: at night (no visible light, but not all dark) ultraviolet sterilization effect is better than daytime (visible light). This is because the “photoreactivation enzymes” in bacteria have different biological effects at different biological times.

During the day, the “photoreactivation enzymes” in bacteria gain energy to repair damaged DNA and form monomer bacteria to resume their living state, while at night, the “photoreactivation enzymes” cannot produce this biological effect. In addition, the flow of people at night is less than in the daytime, and the amount of dust in the air is less than in the daytime.