UPSC Courses

DNA banner


  • 13 May, 2020

  • 3 Min Read

UV Radiation and classification

UV Radiation and classification

  • UV-C:
    • Short-wavelength.
    • Most harmful but are completely absorbed by the Earth’s atmosphere and does not reach the Earth’s surface.
  • UV-B:
    • Medium-wavelength.
    • Biologically active but cannot penetrate beyond the superficial skin layers.
    • Responsible for delayed tanning and burning.
    • Enhances skin ageing and significantly promotes the development of skin cancer.
    • Exposure to UV-B rays can cause DNA and cellular damage in living organisms.
    • Most solar UVB is filtered by the atmosphere.
  • UV-A:
    • Relatively long-wavelength.
    • Accounts for approximately 95% of the UV radiation reaching the Earth's surface.
    • Penetrate into the deeper layers of the skin and is responsible for the immediate tanning.
    • Enhances the development of skin cancers.

UVGI (Ultra violet germs irradiation) Working Method:

    • UVGI replicates UV wavelengths and uses its destructive properties to target pathogens.
    • It disinfects contaminated spaces, air and water and helps in preventing certain infectious diseases from spreading.
    • According to the US Centers for Disease Prevention and Control (CDC), UVGI is a promising method for disinfection.
      • In 2005, the CDC revised its guidelines for using UVGI with regards to the spread of tuberculosis (TB) in hospital settings.
      • The guidelines intended to eliminate the spread of infection to healthcare workers from patients or others with unsuspected or undiagnosed infection.
    • Scientists advise that fixtures containing UVGI lamps can be mounted on the walls or suspended from the ceilings.
      • Such fixtures will shine light on the upper interior surface of a room and trap pathogens.
      • Installing a fan in such spaces can further draw the air upward, which will increase the speed with which the UVGI can destroy pathogens.
    • UVGI lamps can also be installed in room corners, in air ducts of ventilation systems or portable or fixed air cleaners.
    • UVGI fixtures are and should be installed above people’s heads because their short wavelengths can irritate the skin and eyes.

Source: Web

Students Achievement

Search By Date

Newsletter Subscription
SMS Alerts