Do-It-Yourself UVL Sterilizer: SCU Physics Professor Shows How It’s Done

During the outbreak of Coronavirus pandemic, ultraviolet light (UVL) may come in handy with its sterilizing effect against germs and viruses. As regular UVL products may cost over a thousand NT dollars each, Associate Professor Chiou-Min Chen of the Department of Physics at Soochow University demonstrated an easy and inexpensive way to make one.

Researchers have pointed out that Coronavirus can stay active on paper money or coins for as long as 4 hours. So can it on document folders commonly used in schools or government agencies. To wipe out bacteria or viruses, these banknotes, coins, folders as well as used masks need to be placed under UV light for 5 to 10 minutes.

 Surprisingly, an UVL device can be made in just three minutes with accessible and recycled materials that cost only hundreds of NT dollars in total, according to Prof. Chen, who has been reputed as the MacGyver of Soochow University.

“Here we have a tea caddy, a timer from an electric fan, and a recycled lampshade with a mercury lining,” Chen explained how he utilized common or even unwanted materials to make a lite version of a UVL sterilizer. As UV rays, which cannot penetrate objects, could only be effective for the part directly exposed to it, a lampshade is needed for reflection to enhance the bactericidal effect, Chen added.

To complete a whole set of a sterilizing device, a 20-watt UV lightbulb as well as some aluminum foil, tapes and a plastic basin (to make a container to hold things that are to be sterilized) are also needed.

Through an experiment, Chen proved the do-it-yourself UVL sterilizer does have strong bactericidal power as he showed that a piece of bread that had contacted unsterilized coins produced much more molds on its surface after 8 days than the one that had not. And the same results happened on the document folders as well.

However, the UV light is harmful to human eyes, and people should never look directly to the light to avoid any deterioration of eyesight, Chen warned.