1. The disinfection principle of ultraviolet lamp
An ultraviolet lamp also called an ultraviolet disinfection lamp or ultraviolet germicidal lamp is a lamp tube made of quartz glass or other raw materials whose ultraviolet transmittance is not lower than quartz glass.
The principle is to inject mercury vapor into the lamp tube and generate ultraviolet radiation with a wavelength of 253.7nm through a low-pressure mercury vapor discharge lamp that generates ultraviolet rays by discharging the mercury vapor. Ultraviolet radiation can damage and destroy the nucleic acid and bacterial cell protein of viruses, bacteria, and other pathogenic microorganisms, so that they lose the functions of reproduction and self-replication, so as to achieve the purpose of disinfection or sterilization.
Ultraviolet lamps are mainly used for disinfection of air and smooth and flat surfaces (note that it is a smooth and flat surface, it is ineffective for uneven surfaces), and it is also used for disinfection of water and other liquids. It is often used in medical institutions, schools, kindergartens, and other places. It is not recommended for ordinary families to use UV lamps.
2. Be careful when using UV lamps
(1) Strictly implement the relevant regulations for the installation and use of ultraviolet lamps, and standardize the equipment and installation. Classrooms, activity rooms, and other public places, without special needs, generally do not install fixed ultraviolet disinfection lamps but can be equipped with mobile ultraviolet lamps for sanitation and disinfection.
(2) During indoor suspended ultraviolet disinfection, the hoisting height of the lamp tube is 1.8~2.2 meters from the ground.
(3) The ultraviolet lamp and the lighting switch must be set separately and keep a certain distance. It is not allowed to arrange the ultraviolet lamp switch and the lighting switch side by side. The switch setting should be more than 2 meters above the ground, the switch box cover should be added, and a striking warning sign should be affixed to the box cover.
(4) Medical institutions, schools, kindergartens, and other public places need to establish and improve the use and management system of ultraviolet lamps, which should be managed by special personnel. When using, make sure no one is present and avoid sunlight or another lighting.
(5) After disinfection, open windows for ventilation. If an ozone-containing ultraviolet lamp is used, ozone will be generated during the working process, so it is best to open the window for ventilation for more than 30 minutes after disinfection so that the ozone can be dissipated as soon as possible.
(6) Wipe the surface with a 95% alcohol cotton ball regularly. When dust and oil are found on the surface of the lamp, wipe it in time.
(7) Intensity monitoring is carried out regularly every year. The instrument method or indicator card method can be used. When the irradiation intensity of the UV lamp in use is lower than 70μw/c㎡, it is recommended to replace it in time.