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plasma_hand_wash_01.jpg
plasma_hand_wash_02.jpg

Before you protest, as I initially did, that some things are so simple and fundamental that they don’t really need high-tech “improvements,” realize that this device is being developed for and targeted at medical professionals, who, per this New York Times article covering the developing technology, “often have to wash their hands dozens of times a day — and may need a minute or more to do the process right, by scrubbing with soap and water.”

Room temperature plasma is reportedly very effective at sterilizing surfaces, and is already in use to clean inanimate surfaces and instruments. The plasma is produced by ionizing ordinary air, so no separate gas supply is needed. Apparently the central design challenge is making sure the box –which is basically just a high-voltage power supply–is safe to stick your hand into, and remains that way over the lifetime of the device. The plasma itself supposedly causes no discomfort and is safe for the skin, although you’d think, if they really believe that, somebody would’ve provided a photo showing a bare hand in contact with it, rather than one so conspicuously gloved.

Sean Michael Ragan

I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I write for MAKE, serve as Technical Editor for MAKE magazine, and develop original DIY content for Make: Projects.


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Comments

  1. Nate says:

    …the top picture is almost exactly what I pictured in Dune, for Paul’s “humanity test”.

    I don’t know that I want to put my hand in that thing ;)

    1. CircuitGizmo says:

      You beat me to that. (Slow blade and all)

      1. mightywombat.livejournal.com says:

        Wow, I am just slower than slow. That’s exactly what I was going to say…

  2. Sean Michael Ragan says:

    Aw, crap. Hate missing a good pop culture allusion. “Pain by nerve induction.”

  3. EngineerZero says:

    Could this technology be adapted for a home mini-dishwasher?

  4. Alan says:

    I’d want to see some very robust safety tests on this before sticking my hand into one, and not because of the shock hazard. Bacteria and fungi are living organisms, so if you’ve got a physical phenomenon that kills all of the microbes, you can be virtually certain that it’s doing at least some damage to your skin cells. UV light also kills microbes, for example, and if you blast your skin with enough of it over time, you develop one of the deadliest forms of cancer. How do we know room-temperature plasma (and the reactive chemical species it produces) won’t have the same effect?

    1. Zool says:

      I was thinking the same thing, it must have a biological effect on humans if it can affect Bacteria and fungi. Also High voltage discharges would most definitely result in biological damage in the same way other Free Radicals cause biological damage. i.e. http://en.wikipedia.org/wiki/Free-radical_theory

      On top of this, I’m also not at all convinced such a device would be that effective as the coverage of the hand would be incomplete. On top of this, anyone who unknowingly put a wet hand in there (with also a wet arm) is at risk of have shall we say, an interesting experience they will not forget! ;)

      If all that isn’t enough, on top of these issues, any contact with the outside of the box negates the cleaning effect of putting your hands in there, because as soon as you remove your hands you are likely to touch unclean outer surfaces of the box (this last design fault is also shared with the Dyson hand air dryer machines).

      Apart from that, it looks a lot of fun!. :) … now where’s a florescent tube and some old neon bulbs to shove in there to see some lightning effects. :)

    2. Kyle says:

      There’s not exactly a shock hazard. It’s plasma. It’s AIR you’re being hit with. Air that’s being torn apart in a very specific way. There’s not going to be some super bacteria against it. Nothing lives in a star, and that’s not just because of the heat.

      Beyond that, the stuff is targeted. I’m sure they are testing for things like cancer anyway, but plasma is *NOT* light. Thinking it’s similar to light in any way is a mistake.

  5. BobsYourUncle says:

    Appears to use the same technology that were used for air purification which have not-surprisingly vanished from the market. High electrical field creates ozone and free-radical oxygen. Ozone destroys practically everything biological it encounters, which is great for getting rid of germs, equally as good at destroying your skin.

  6. RocketGuy says:

    But “room temprature” and “Plasma” seem contradictory. I’m under the impression that plasma is created only at tempratures that exceed a material’s ability to stay a gas, generally pretty high.

    I could see where it’s a very low *heat* plasma, given that there isn’t much mass at high temperature in this application, but I suspect that the marketing folks have once again missed a fine distinction between temperature and heat.

    While it might be faster than soap, I do wonder along with the other posters about how much damage is done to the epidermis. I’d want to have the hand be still and an armature calibrated for the right exposure time moving instead.

    1. Sean Michael Ragan says:

      I share slightly in your cognitive dissonance here. This is from David Grave’s webpage at UC-Berkeley. He’s one of the scientists named in the NYT article:

      “Research in the Graves group focuses on the fundamentals and applications of weakly to partially ionized gases, or plasmas, to technological problems, primarily in the microelectronics industry. These plasmas operate at relatively low gas temperatures – around room temperature – and are therefore quite different from the hot, usually strongly magnetized plasmas in stars or that are used in thermonuclear fusion and weapons applications. ”

      http://graves-lab.cchem.berkeley.edu/overview.html