Ultraviolet germicidal irradiation

🔹 About: 

1. It is to detect the virus in public places and disinfect contaminated public spaces to stop the transmission of the virus.

🔹 UVGI Working Method:

1. It replicates UV wavelengths and uses its destructive properties to target pathogens.

2. According to the US Centers for Disease Prevention and Control (CDC), UVGI is a promising method for disinfection.

3. Scientists advise that fixtures containing UVGI lamps can be mounted on the walls or suspended from the ceilings.

4. It can be installed in room corners, in air ducts of ventilation systems or portable or fixed air cleaners.

🔹 Effectiveness:

1. Sensitivity of microorganisms to UVGI.

2. Dose/ intensity of UVGI required to kill pathogens.

3. Humidity and weather conditions.

4. Air circulation in a room.

🔹 Facts: 

1. The use of UVGI on a mass-scale in public spaces like schools, universities, restaurants and cinema halls is not a very cost-effective way for disease prevention.

2. The Defence Research and Development Organisation (DRDO) has recently developed automated contactless UV-C devices namely DRUVS (Defence Research Ultraviolet Sanitiser) and NOTESCLEAN.

🔹 UV Radiation Classification:

1. UV C: Short-wavelength radiation; Most harmful but are completely absorbed by the Earth’s atmosphere and does not reach the Earth’s surface.

2. UV B: Medium-wavelength radiation; 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; Most solar UVB is filtered by the atmosphere.

3. UV A: long-wavelength radiation; 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.