Since COVID-19 outbreak, personal protective masks, including general surgical masks and medical care mask) are highly attention, and become the epidemic prevention and control of the standard, in the production of masks, surgical masks must be in strict accordance with the relevant standard to production and disposable respirators, strictly in accordance with medical supplies, disinfection procedures to parse and disinfection of masks, can put into market.
Current mask manufacturing enterprises are generally of the mask by ethylene oxide sterilization, and after disinfection, there will be a part of the ethylene oxide residues in the surface of the mask, ethylene oxide is a kind of toxic carcinogens, in the use of ethylene oxide sterilization of masks after disinfection, often have to pass a resolution for 14 days, this creates some areas remain masks the shortage of medical material.
The following is a kind of effective sterilization method for the sterilization of masks: ultraviolet germicidal lamp sterilization.
Sterilization mechanism of ultraviolet germicidal lamp:
1. Promote the death of microorganisms due to the loss of DNA conversion ability.
2. Destroy the amino acids of the bacterial proteins, and make the bacterial proteins photolysis and denaturation.
3. The activity of oxidase in bacteria was reduced, and the oxidation ability was lost.
4. Ionize the oxygen in the air to produce ozone with a strong bactericidal effect.
Application of ultraviolet germicidal lamp in medical environment. The use of ultraviolet lamp to sterilize the air in the hospital has a history of decades, the use of static air direct illumination method and moving air disinfection method combined to treat the disinfection space and facility object surface for standard safe and clean disinfection. Among them, the work of the flowing air sterilizer is to sterilize the air through the indoor air circulation, so as to achieve the purpose of disinfection of the whole indoor air. The structure of this kind of disinfecting machine mostly takes the shell of indoor machine that USES household air conditioning.
Monitoring the intensity of ultraviolet germicidal lamp tube is the key to ensure its disinfection effect.
Methods for monitoring the intensity of ultraviolet germicidal lamp tubes:
(1) By uv intensity
Measurement: after the ultraviolet lamp is irradiated for 2 minutes, the ultraviolet intensity meter is placed in the center of the ultraviolet lamp, which is 1m vertical, for irradiation until the instrument pointer does not move, that is, the intensity value of the ultraviolet lamp.
(2) Use the uv intensity and disinfection dose indicator card: place the card at the center of 1m from the uv lamp and point one side of the design towards the lamp. Irradiation 1 m in(should be accurate). The coating in the middle of the design changes from white to fuchsia, and the intensity of irradiation can be measured by comparing with the surrounding corresponding color blocks. The new lamp tube should be qualified as ≥100uw/cm2, and the old lamp tube should be replaced if it is less than 70uw/cm2.
(3) Daily record of use time: the domestic lamp tube service period is generally 6000 hours when the specified period of use 3/4 should be replaced.
Problems needing attention in the application of ultraviolet germicidal lamp tube:
(1) The lamp tube surface should often (generally every 2 weeks 1 time) with alcohol cotton gently wipe, remove dust and oil above, in order to reduce the impact of ultraviolet penetration;
(2) When disinfection, the room should be kept clean and dry, there should be no dust or water mist in the air, the temperature should be kept above 20℃, the relative temperature should not exceed 50%;
(3) To prevent radiation damage, when using, if the person is in the room, should avoid facing the light source, and cover the exposed skin with clothes and hats; When monitoring the intensity, the light source should be observed with the back, and ordinary glass mask or sunglasses can be used to protect the eyes and facial skin.
(4) Intensity monitoring, should be 3~6 months for a radiation intensity detection, found that the intensity of the lamp should be replaced in time.
Application range of ultraviolet germicidal lamp
· disinfection of water bodies in food processing industry, including juice, milk, beverage, beer, practical oil, and water for all kinds of canned and cold drink products.
· ultra-pure water for the electronics industry.
· disinfection of water in hospitals and various laboratories, and disinfection of wastewater caused by high content of diseases.
· application of water disinfection, including residential buildings, communities, office buildings, hotels, restaurants, water works, etc.
· purification and disinfection of aquatic product processing, shellfish purification and disinfection of fish processing, etc.
· military barracks and field water supply system.
· urban sewage disinfection, the maximum treatment capacity can reach more than 1 million tons per day.
· disinfection of swimming pools and other recreational water on water.
· cooling water disinfection, including thermal power, nuclear power plant cooling water, industrial production cooling water, central air-conditioning system cooling water.
· cooling water for biological, chemical, pharmaceutical and cosmetic production.
· seawater and fresh water for seedling and breeding (fish, eel, shrimp, abalone, shellfish, etc.), the total treated water can reach more than 200,000 tons per day.
· agricultural water disinfection, including greenhouse water, irrigation, etc.
As an efficient, fast and pollution-free disinfection method, ultraviolet germicidal lamp has always been the first choice of disinfection measures in medical, drinking water, food and other professional fields, and was favored in the outbreak of COVID-19.