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Hardware Technology

Zinc Whiskers Cripple Colorado's Computers 276

Mr. Christmas Lights writes "While zinc whiskers, small metallic fibers which grow on surfaces that have been electroplated with zinc, aren't a problem for Christmas lights, they can cause serious problems for computers. The Denver Post reports how they caused computer outages for the last three weeks in the Colorado secretary of state's office. This basically halted business and elections document filings. Zinc whiskers are becoming more of a problem as computers electronics get smaller. NASA has a good reference site which includes a interesting PDF summary paper complete with pictures. /.'ers with computer rooms might want to check this out."
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Zinc Whiskers Cripple Colorado's Computers

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  • Wow! (Score:4, Funny)

    by MikeXpop ( 614167 ) <mike&redcrowbar,com> on Friday July 02, 2004 @09:37PM (#9597440) Journal
    Shocking! /sorry, couldn't resist.
  • ...with a magnet!
  • by stratjakt ( 596332 ) on Friday July 02, 2004 @09:40PM (#9597455) Journal
    Zinccccccc Zinnnccccc! Oh my god what have I done!

  • Tiny little bits of a conductive material are rarely good news for electronics.

    I am wondering if they will have some sort of sheilding system for this in the future, if it becomes more of a problem. That could be as simple as a small layer of some nonconductive resin on the surface of the circuits. But will it ever be economically feasible?

    I suppose in the mean time we'll have to do our own safeguarding if we are in a risky area.

    • Not sure .. NASA has used an inch of the strongest apoxy that we know of .. and the whiskers just grew right through it.
    • I think just setting up The Ionic Breeze from The Sharper Image would be the killer app solution to this problem. Having positively charged metal in the room would be a magnet-like draw for this stuff that'd prevent it from being drawn to the computer equipment by airflows created from cooling fans.

      A HEPA-quality air filter is also suggested... on the same concept. It'd be a fan-based air draw that'd trap any of these things coming through and therefore reduce the chances that any given particle lands insi
    • I suppose in the mean time we'll have to do our own safeguarding if we are in a risky area.

      Hmmmm, seems like if you wanted to grow something like zink whiskers, you'd want a nice stable environment, free of foreign contaminants, and time, lots of time. From this standpoint, a dusty garage is a safer environment than a carefully controlled data center. Problems with monocultures.
    • It's called "conformal coating". It protects circuits against humidity, conductive contamination, fungus, and other environmental hazards. There are two big reasons PC manufacturers don't use it:

      Anything that adds cost and isn't absolutely essential doesn't go into a product with merciless cost pressure. Consumer-grade PCs will last for years in home use without the conformal coating, so they don't have it.

      Anything that increases production time and isn't essential doesn't go into a high volume product. A

  • by calags ( 12705 ) on Friday July 02, 2004 @09:43PM (#9597473)
    I guess we have to shave all zinc cats before we let them into the building.

  • by the_rajah ( 749499 ) * on Friday July 02, 2004 @09:44PM (#9597479) Homepage
    The metal frames for the raised floor are where the zinc whiskers are coming from. They get sucked into the power supplies and short them out.

    "Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
    • Yup.

      And the metal that the whiskers come from, have been used for computer room floor tiles, racks, and even (shudder) PSU cases.

      Now that's scarey.
    • Which effectively means that it's a component of dust... so if you have dust buildup in your room, you're likely to find this among other problems forming.
    • by SuperBanana ( 662181 ) on Friday July 02, 2004 @11:18PM (#9597817)
      The metal frames for the raised floor are where the zinc whiskers are coming from. They get sucked into the power supplies and short them out.

      I'd be a lot more inclined to believe the "whiskers" are coming from movement of the tiles when people walk across them(they do shift, as does the frame slightly) and not some "growing whiskers" BS.

      Furthermore, the problem is easily solved via any/combination of these:

      • Using the floor for return only(ie, suction) and using good air filters in the A/C units
      • Using ducted A/C under the floor if you must do supply via the floor
      • Regular maintenance, ie blowing the dust out of power supplies and such, combined with some sort of vacuum to collect the dust you raise
      • Using filters in equipment itself
      • Wiping all surfaces down with swiffer-ish cloths on a regular basis, ie dusting the place.

      Furthermore, if the little buggers are metallic, why don't you just install a few small but powerful magnets in various ducts? A metal grate made up with a set of magnetic rods would probably work like a swell charm, and only require periodic cleaning...

      • by the_rajah ( 749499 ) * on Friday July 02, 2004 @11:37PM (#9597877) Homepage
        No, I'm not worried about zapping floppies. Your ideas are, for the most part very good ones, but zinc is paramagnetic, if I recall right, and is not attracted to the magnets. Same for tinfoil, BTW. The magnets would be effective in catching iron filings and related ferromagnetic particles, though, but that didn't seem to be the reported problem in this case.

        Your friction hypothesis has merit, too, but growth of whiskers, more scientifically known as dendrites is actually quite common, especially where electric fields exist between conductors. I ran into that in a flexible touch keyboard we had designed using a silver alloy that was screened on as the conductors. Durn things would develop shorts after a while in the field, literally since it was on agricultural equipment. You couldn't see the shorts, but examination under a microscope revealed those nasty little whiskers. A metalurgist was consulted and provided a different alloy that solved the problem.

        "Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
  • by jeremyol ( 179746 ) on Friday July 02, 2004 @09:46PM (#9597494) Homepage
    We are in the final streach for replacing the entire datacenter floor where I work because of zinc Whiskers. We had the underfloor area cleaned for the new A/C that blows from the floor up. We promptly lost 11 power supplies and the total count is up over 20 now. We did verify the presents of zinc whiskers in the dead powersupplies thanks to the onsite electron microscope.
    Thankfully the high temperature never got above 85 degrees so the old A/C was able to keep up.
    • Tiny wires? (Score:3, Interesting)

      If these things are so small as to require an electron microscope to see, why arn't they simply vaporized/melted as soon as they find themselves shoved between two (relativly) massive wires?

      You'd think that a microscopic piece of zinc would go before a macroscopic fuse/chunk of copper/etc. And since it's alot of single pieces blown around, it's not like several million are all going to do it at exactly the same time.

      I've melted zinc, and it's pretty snappy, (Pennies after 1982 are mostly Zinc. When you me
      • If you read the NASA PDF, it notes that you need a certain amount of milliamps to fry the Zinc, so if there's any place where there's a low power device(1W, I'm thinking), then the Zinc would short the device, but it wouldn't get fried in the process, causing a permanent short.
  • It's ... (Score:3, Funny)

    by ngdbsdmn ( 658135 ) on Friday July 02, 2004 @09:46PM (#9597495)
    ... amazinc.
  • Google cache (Score:3, Informative)

    by akgoatley ( 787022 ) on Friday July 02, 2004 @09:47PM (#9597498) Journal
  • by winkydink ( 650484 ) * <sv.dude@gmail.com> on Friday July 02, 2004 @09:51PM (#9597519) Homepage Journal
    I thought almost all quality electronic devices have a conformal coating (non-conducting polymer) applied to PCBs? Colorado must be buying el-cheapo crap. Remember, you get what you pay for.
    • Colorado must be buying el-cheapo crap.

      They are not the only ones. Case moders, the hard core ones that use hacksaws, die and tap sets, and large large hammers need mounting hardware. Frankly I never thought twice about buying zinc #6 machine screws/bolts from the local hardware store. While I keep a collection of misc bolts and such, there are those days when I just need a screw. It looks like I have to be more cafeful were I get my screws from.
    • I thought almost all quality electronic devices have a conformal coating (non-conducting polymer) applied to PCBs?

      Generally, no. Conformal coating is normally only used on circuit boards which will be exposed to extreamly harsh conditions. Unless the designers expect the circuit board to come into contact with liquids or corrosive gasses during typical use, the circuit board will not be conformally coated.
    • by Animats ( 122034 ) on Friday July 02, 2004 @10:58PM (#9597743) Homepage
      I wish. Automotive electronic units are routinely conformal coated, but most consumer devices are not. Many blank boards have a masked insulating layer on top, but that's different than a conformal coat. A conformal coat is applied after the parts are mounted, so the whole board becomes a sealed unit.

      You can conformal-coat boards yourself, using Fine-L-Kote spray. [yahoo.com] We use this stuff on the Overbot [overbot.com].

      It's a flammable, toxic chemical mixture until it dries; you need gloves, goggles, a respirator mask, and proper flammable liquid storage. Cover connectors with masking tape before spraying. It's a clear coat, but glows in UV, so you can check for missed spots.

    • Conformal coating is standard procedure for military electronics. It makes repair a pain in the ass, but it's not like consumer electronics gets much component-level repair anyhow. It also protects against fungus, which is important since most of us are kept in the dark and fed fertilizer.
    • it may delay whisker production, but it won't prevent it.
  • by Zarquon ( 1778 ) on Friday July 02, 2004 @09:51PM (#9597520)
    And are a problem with the new lead free processes.. especially as lead spacing decreases, and the euro lead-free requirement kicks in.

    Agere wrote a good article in Analog Zone, available at http://www.analogzone.com/grnt0216.pdf [analogzone.com]. It has a good micrograph showing the problem.
  • by Anonymous Coward on Friday July 02, 2004 @09:52PM (#9597524)
    I work in a large midwest hospital, and we've got a constant issue with Zinc whiskers in our network jacks in operating rooms. Supposedly the origin is the cleaning solutions that they use for the floor.
    • For anybody thinking "zinc whiskers in an operating room, isn't that bad for the patients?"... remember, zinc is found in vitamin tablets. It's actually good for the human body.
      • Zinc metal is not the same thing as zinc in vitamins, which is Zn oxide or sulfate. Your statement is roughly equivalent to "well sodium is in salt, so sodium metal must be perfectly safe."
        • by Artifakt ( 700173 ) on Saturday July 03, 2004 @12:56AM (#9598175)
          The preferred Zinc compound for mineral supplements is usually Zinc Picolinate, which is the form most readily metabolized by humans. Zinc Oxide is frequently the form used in mixed multi-vitamin and mineral tablets, but some nutritionists argue that the manufacturers are cutting corners to save a few cents there.
          Zinc Oxide is also absorbed very, very slowly through the skin (as when used in sunblock cremes, so that most of the sunblock's Zinc is washed off instead of entering the body). Pure Zinc metal is not nearly as reactive as sodium or calcium, so it really isn't very toxic compared to them. People eat pennies frequently (4 year old people that is), with few harmful effects, although pennies are mostly zinc with a copper surface.
          For comparison, a significant amount of pure sodium won't just give you chemical poisoning, it will oxidize so rapidly with contact with air or water, and liberate so much heat in the process, that the burns you would get from handling or swallowing it would probably kill you as fast as the toxicity, or even quicker.
          Yes, Zinc metal fiber in a hospital environment isn't nearly what I would call perfectly safe. Pennies usually pass before too much dissolves, and getting a lot of metal fibers inside a surgical incision before closing is not such a benign environment. Still, there are a lot worse possibilities for substances to get in a wound.
          • Since you seem to know your stuff, I have a question for you. Why does it matter what the counter ion is? Once it's in solution, doesn't the Zn++ dissociate? And once it dissociates isn't it just going to flow down its concentration gradient?

            btw, the extremly exothermic reaction of metallic sodium and water is what I was getting at with that comment.
  • We have 3 rooms where I work that house our servers. We are migrating some stuff over to an HP-UX system running oracle. When we had some HP representatives come over to our area to check out the place we intended to house the HP servers, they insisted that zinc whiskers could potentially be very damaging and that we make sure our rooms were clean and free of zinc whiskers (not that our rooms were particularly dirty). I always wondered how legitimate their claims were.
  • Zinc Whiskers? Hey, they stole my username!

    Ok, no they didn't.
  • by ErichTheWebGuy ( 745925 ) on Friday July 02, 2004 @10:06PM (#9597578) Homepage

    #931654: "Sorry, our computers seem to be growing metallic whiskers. What did you say your username was? bwahahahahaha"
  • by teamhasnoi ( 554944 ) <teamhasnoi@yahoo. c o m> on Friday July 02, 2004 @10:08PM (#9597584) Journal
    but old Hammond organs get a greenish-white 'film' or coating on the metallic chassis and parts. Humidity seems to make it worse.

    My A-100's chorus/vibrato likes to go on summer vacation when it gets humid in the house, but works fine during the winter. Just thought I'd throw that in - I think the stuff is zinc-plated...

  • ...small compact computer designs get these whiskers easier. I don't doubt it happens, but where are all the millions of laptops shorted out then, or the mini itx machines,game machines, etc?

    Is there something else here causing whiskers to grow some places and not in others, even though both have zinc?
    • These whiskers take time to grow and are fragile, you would need to have a situation where the equipment is undisturbed for a period of time, this allows the whiskers to grow, then when there is a disturbance (ie construction vibration)they break off and can cause shorts. I don't think most people leave their computer undisturbed for long periods of time
      dendrite growth [reliabilit...sislab.com] has a different mechanism can also have similar consequences. This happens in things like old electrical systems, where you can have mois
  • by danlor ( 309557 ) on Friday July 02, 2004 @10:42PM (#9597697) Homepage
    and a narative
    Access Floors [accessfloors.com.au]
  • And Sea-Water too. (Score:5, Informative)

    by OceanWave ( 192467 ) on Friday July 02, 2004 @10:52PM (#9597727)
    I know I speak against my own name, here. But:

    Living by the sea, especially with the high humidity that comes with it...and the salt...can give your more than just a few zinc whiskers on the PC board.

    Salt oxidation--depending on how long the windows are open--can really eat a PC in two years or less; never mind the quality of the MB.

    Sea salt is hydrophilic. If it accumulates on something, episodes of high humidity will attract moisture from the air, and add the basis for typical corrosive effects. I have had containers with dry sea salt, which have pulled moisture out of the air on their own.

    (Most acids need water...so does salt to release it's own ions, which can have a corrsive effect similar to an acid on metallic equipment...usually involving the non-metal in the salt. Sea salt has lots of chlorine, a very strong oxidizing agent.)
  • ...green dots are an audio solution. This smacks of freakish pseudoscience masquerading as real problems. Kind of like the gold plated power cords for stereos that cost audiophiles $180 each. The supposed reason that they improve sound is that gold has less resistance and therefore your amp will perform better if the electricity gets to it more readily. That's bullshit just like the zinc whisker issue.
    • There is a value to gold connectors, they don't tarnish, ergo, the connection doesn't degrade.
      Is it worth the extra money? Not usually, but there is a benefit.

      However, I do love when I hear people talk about improved 'sound quality'.
      I always ask "So, the wires are gold as well?"
      Usually the light downs.
      I wil admit I have been out of the audio[hile loop for about 20 years. It seemed the widespread use popularity of CD's brought with it a large number of idiots who thought they where 'ausiophiles'.

      Us a marke
      • There is a value to gold connectors, they don't tarnish, ergo, the connection doesn't degrade.
        Is it worth the extra money? Not usually, but there is a benefit.


        Tin and lead tarnish yet it's still very common place. Silver also tarnishes yet is, or at least was common place on larger ships. Aluminium tarnishes practicly the moment you expose it to air. The wisdom to what you say is the fact that a copper tarnish aka copper oxide is an insolator.

        I've been upgrading to gold connectors simply because i've
      • No, this is real. Here's why: a tarnished connector can become a non-linear junction. Tarnish such as a thin film of a sulfide, in contact with a 'pure' metal, can be a rectifier. If you put one on a curve tracer, you could actually see this. So there really is merit in a gold, i.e., non-corrodable, connector.
    • The real reason for gold plating has more to do with oxidation than the resistance of the different metals. Dending on where you live, those connections can develop problems fairly quickly. I also had someone point out that they paid a LOT of money for their equipment and don't want any dissimlar metal issues. While I'm not sure about the odds of that being an issue, who am I to quibble with him over a 100 dollar cable to hook up 3000 dollar rack equipment?
  • sweet! (Score:4, Funny)

    by rsilvergun ( 571051 ) on Friday July 02, 2004 @11:22PM (#9597833)
    I work tech support. I can't wait to start using this as an explanation of all sorts of things:

    Customer: When I go on mah Innernet, I get this error 'bout id not bein' displayed.

    Me: Sir, it looks like you've fallen victom to Zink Wiskers. No sir, you don't need to get rid of your cats.
  • by Mr. Neutron ( 3115 ) on Saturday July 03, 2004 @12:08AM (#9598008) Homepage Journal
    This basically halted business and elections document filings.

    They'll do anything to keep Nader off the ballot in a swing state. :-)

  • by SiliconEntity ( 448450 ) on Saturday July 03, 2004 @12:18AM (#9598039)
    I live within a mile of the ocean, and we have a lot of fixtures in our house which must be made of zinc, because they grow these whiskers just like were described. We have a chandelier in particular which looks like it's brass, but it's always covered with fuzz. Then I have a chin-up bar in a doorway and the same thing happens to it.

    I wonder if it has to do with some kind of electrochemical reaction, where maybe there have to be different unlike metals with varying electronegativity, and enough humidity to get a low grade current flowing between them. I never saw this problem, when I lived elsewhere. But if my computers had zinc in them I'm sure it would grow whiskers just like the rest of my house.
  • similar (Score:2, Interesting)

    by sydres ( 656690 )
    problem happens in copper wiring small copper "whiskers" grow right through the insulation. if two wire are close when this happens they can short out and cause fires. usually only happens in really old wiring
  • by iamacat ( 583406 ) on Saturday July 03, 2004 @02:38AM (#9598501)
    "It's not my code, it's the zinc whiskers"

    As I recall, old computer used to suffer from mice chewing on the wires and they used to keep a cat to keep the programs running smoothly. Then it was bugs and I am not sure if spiders helped or added to the problem.

    I, for one, welcome our new zinc-eating nanobots.
  • Yup (Score:3, Informative)

    by Zog The Undeniable ( 632031 ) on Saturday July 03, 2004 @02:13PM (#9601182)
    My company has just had to replace the floors at two large data centres because of zinc whiskers. The replacement floor panels will be galvanized, not electroplated.

    And before anyone points out that they're the same thing, they're not. Galvanizing involves dipping steel into molten zinc. Despite the name, it has nothing to do with galvanic action, electroplating or Mr Galvani. Galvanized panels don't suffer from zinc whiskers, anyway.

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