Students' invention offers germ-free door handle

Students’ invention offers germ-free door handle

Two high school students, Sum Ming Wong and Kin Pong Li, both living in Hong Kong have designed and built a door handle that kills germs, thus preventing the spread of disease through hand contact. They demonstrated their handle at the Intel International Science and Engineering Fair held last month in Pittsburgh—taking second place in the materials science category.

One of the ways that ailments such as cold and flu are passed is via contact, and one of the main avenues is via —a sick person coughs into their hand then uses the handle to enter a bathroom, office, or other location, depositing . Others that enter the same room pick up the germs from the door handle and invite the germs into their own bodies by touching their eyes or noses. Door handles that kill such germs on contact would stop them from spreading—that is what Wong and Li set out to build.

The pair started by noting that a mineral called titanium dioxide is quite toxic to germs, but it hasn't been used as an antibacterial agent much because it requires the presence of UV light. To get around this problem, the team ground some of the mineral and then used it to coat a glass tube, they then affixed a LED onto one end of the tube—it shines UV light onto the insides of the glass tube—any germs that land on the outer side are then killed by the mineral (testing showed it to be 99.8 percent effective). Putting the glass tube onto brackets allowed for it to be used as a door handle.

But that wasn't the end of the story, realizing that hooking the handle up to an electrical outlet would be messy, and relying on batteries would be iffy, they put together a gear box that allows for capturing energy from the door opening and closing. That energy is then sent to a battery that feeds power to the door handle, keeping it lit all the time, not only killing germs, but making it easy to see. Amazingly, the co-creators report, building the door handle only costs about $13—minus labor. At this time it is not clear if the two students will be attempting to market the door handle, but it would seem a good idea. Also, it appears the same design could work in other areas, such as with shopping carts, handrails on escalators, etc.


Explore further

Silver coating kills bacteria on campus door handles

More information: student.societyforscience.org/ … r-handle-kills-germs

© 2015 Phys.org

Citation: Students' invention offers germ-free door handle (2015, June 22) retrieved 20 October 2019 from https://techxplore.com/news/2015-06-students-germ-free-door.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
379 shares

Feedback to editors

User comments

Jun 22, 2015
or you could just make doorknobs and touch surfaces with a thin layer copper. brass. or bronze.

these naturally kill germs

https://en.wikipe...surfaces

but its a cool looking door handle

Jun 22, 2015
Also consider making:
- toilet seats powered by the water flow when flushed.
- sink handles powered by the water flow.

Jun 22, 2015
At this time it is not clear if the two students will be attempting to market the door handle, but it would seem a good idea.

They'd be mad if they didn't. You could sell doorhandles like this at 50$ a pop to hospitals and medical practices (and people who are paranoid about germs at home), easily.

Jun 22, 2015
This might work, if everyone actually used the door handles.

Jun 22, 2015
This is dumb, copper alloy handles work just as well.

Jun 22, 2015
This is dumb, copper alloy handles work just as well.


But then you would miss out on the Hawthorne Effect:
https://en.wikipe...e_effect

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more