What is the disinfection principle of ultraviolet lamp?

<p>2. Disinfection method of ultraviolet ray&nbsp;is mostly used for disinfection of air and object surface, the wavelength is 200~275nm. Used for air disinfection, the effective distance is no more than Zm, the irradiation time is 30~60min, used for disinfection of articles, the effective distance is 25~60cm, the irradiation time is 20 ~ 30min, the timing starts from 5~ 7min when the lamp is on (the lamp needs to warm up for a certain time, to make the oxygen ionization in the air to produce ozone).</p><p><strong>How long does the ultraviolet lamp shine properly</strong></p><p>