Common methods of air disinfection in biosafety laboratories include ultraviolet irradiation, chemical disinfectant spray, etc. Because ultraviolet radiation needs to directly irradiate the surface or gas of the object to be sterilized, it cannot effectively sterilize the wall surface, floor, work surface, etc. that are blocked. Therefore, gas is basically used in the disinfection of high-level biosafety laboratories. Fumigation disinfection method.
1 Formaldehyde
The disinfection effect of formaldehyde gas is greatly affected by the ambient temperature and humidity, and the temperature and humidity should be strictly controlled within the specified range during disinfection. At temperatures higher than 20°C, formaldehyde gas can kill all microorganisms and their spores, but has no inactivation on prion proteins. Formaldehyde disinfection takes a relatively long time and requires a relative humidity of about 70%.
Formaldehyde fumigation has become a common disinfection and sterilization method in China because of its advantages of broad-spectrum sterilization, convenient use and low price. However, due to the pungent odor of formaldehyde, its gas can irritate the eyes and mucous membranes, and it has been confirmed that it has a carcinogenic risk. After disinfection, it needs to be neutralized and then exhausted and ventilated. Because formaldehyde will leave residues after disinfection, attention should be paid to wiping to remove trace residues on the surface of objects.
2 Hydrogen peroxide
Hydrogen peroxide has the characteristics of broad-spectrum, high-efficiency, quick-acting, non-toxic, corrosive to metals and fabrics, greatly affected by organic substances, good stability of pure products, and unstable diluents. Other ingredients are often added to existing products to stabilize hydrogen peroxide, enhance its bactericidal effect and reduce its corrosivity. The main advantages of hydrogen peroxide disinfection are drying, rapid action, non-toxicity, and no residue.3 Chlorine dioxide
Chlorine dioxide is different from general chlorine-containing disinfectants. It mainly exerts its disinfection effect through oxidation rather than chlorination, thereby avoiding the production of organic chlorides during the disinfection process. It has the characteristics that the bleaching effect and the disi