Video

Zapping bugs

Sanjay Kumarasingham (Watercare Services Ltd) talks about how microorganisms and viruses are zapped by UV radiation with a wavelength of 254 nm.

Transcript

SANJAY KUMARASINGHAM The ultraviolet disinfection is a very interesting process. By UV disinfection, you are basically killing the bad guys. There is a certain wavelength at which bugs, viruses and pathogens become zapped. So all you have is ultraviolet light, and that is radiating out at a certain wavelength. And at 254 nanometres, the DNA structure of the microorganism gets dormant. It affects the DNA structure so the bugs cannot reproduce. And for all intentions and purposes, it is considered to be dead. So what you have is a plant which has got the ability to zap the microorganisms, as it swims past the bugs, and at the end of it, you do not have any of these UV rays carrying through, nothing of that sort, because it’s actually at a microbial level affecting just the cells.

Rights: The University of Waikato
Published:29 July 2008