Worse RoHS Madness

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Hi to all,

Been doing a little digging on the apparent banning of CdS cells as a result
of the EU's infamous "RoHS Directive" and came across a nice example of how
INSANE  the whole RoHS business really is.

The case involves semiconductor maker Vishay Semiconductor (Austria) and
high voltage, glass encapsulated diodes.

Background:
--------------

Glass used in electronic components is  ALLOWED  to have lead in it  -
normally as PbO ( lead oxide). The face plates of  CRT tubes being the main
example, where the lead helps stop X-rays being emitted.

The use of tin-lead solder has been banned as is Pb in the plating used on
component leads  -  so most component leads are now plated with pure tin
rather than tin-lead alloys.

The maximum percentage of Pb allowed in any such coating is 0.01% (or
1000ppm ) by weight.

The problem Vishay found:
------------------------------

The glass used to make high voltage diodes contains a small percentage of
PbO -   it lowers the melting temp, improves the flow of the material and
eliminates defects like included bubbles.

But when an engineer at Vishay checked the plating on the connecting leads
of finished diodes, he found that some of the Pb had leached out from the
glass and contaminated the pure tin coating under and adjacent to the glass
bead. Lab tests revealed that the percentage of Pb in the coating was around
0.3% in these areas -  ie 30 times the limit !!!

Horrors  !!!!!

The parts do *NOT * comply with the RoHS Directive  !!!!

The amount of Pb that leached out of the glass bead was utterly miniscule -
something like 5 to 10  *micrograms* per diode (see my note at end).

Vishay even tried using non-leaded glass of various types make the same
diodes, but without success.

Eventually Vishay gave up experimenting and filed an application for an
exemption from the RoHs directive -  no simple task and not that often
successful.

The bureaucrats who pontificate on these things suggested Vishay try using
Nickel or Gold to plate the diode leads and see if the Pb still leaked out.
It did.

Eventually, the exemption was granted:

See #37 in this list -

http://www.rohs.gov.uk/Docs/Exemptions%20without%20link%20backs/RoHS%20Exemptions%20-%20Lead%20 (2).pdf


An interesting comparison:
------------------------------

In the example just given, the issue involved about 10 micrograms of Pb per
diode.

Takes 100 million such diodes to reach 1kg of  Pb

-  that's a LOT of diodes, right  !!

During WW2 something like 10 billion rifle calibre bullets were expended all
over Europe -  not to mention WW1 or all the other countless previous wars.
The total number must be several times more.

Nearly all of these bullets are lying in the ground somewhere, while others
landed in the lakes and oceans that surround Europe. Each of bullet
contained about 10 to 12 grams of Pb.

So, spread all over the European landscape are billions of these lumps of
Pb.

The total weight of which is circa 250,000 tonnes.

I wonder if we will soon see the creation of an RoHS bullet.

Only socially responsible to have safe bullets.




.....  Phil






Re: Worse RoHS Madness



"Phil Allison"

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** See section 6 in the pdf file. :

www.buyusa.gov/europeanunion/era_assessment_rohs_seven.pdf



.... Phil




Re: Worse RoHS Madness


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It's the Register, but it's relevant:

http://www.theregister.co.uk/2006/09/18/lead_free_bullets /

On the more serious side, there is this mob who appear to manufacture
and sell the real thing:

http://www.barnesbullets.com /

and this one:

http://www.frangiblebullets.com /

and a number of others. It seems that horse has bolted.

regards
Terry



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There are reasons for bullets other than lead, because many are NOT used for
killing people.
(And for ones that are, where the victim is wearing a Kevlar vest)

The use of lead shot in shotgun cartridges causes lead pollution in
waterways from duck hunters for example.

MrT.





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dont they use stainless steel pellets now ??
mark



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Oh FFS, that's ludicrous, you can't have lead bullets because they might
hurt someone?

--
Clint Sharp

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I presume the idea is that if you're an avid sport shooter using
lead-based ammunition that you end up consuming a fair amount of the
lead over time. My guess is that some of it is atomised and released as
the slug leaves the muzzle.

If you're going to be shooting every week as keen sport shooters do,
then it's as much a safe-guard for yourself as the environment.

Terry


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Good point I suppose, I can't imagine the fumes from whatever propellant
is used would be doing you much good either. Then again breathing most
sub-micron particles isn't too healthy, if they're chemically inert and
non toxic that's one small consolation.

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Excuse my ignorance, is a sport shooter a target shooter?
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--
Clint Sharp

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**Indeed. Primers are a potentially more serious source of lead inhalation
for shooters. How many shooters wear respirators? I've never seen any. Kinda
explains a lot. How many shooters collect their lead from the environment?
I've never seen any bother. Smokers get a hard time for chucking their butts
on the footpath (and rightfully so), yet no one complains about shooters
leaving their poisonous mess behind.


--
Trevor Wilson
www.rageaudio.com.au



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  Welp..... that explains John-Melb's in a nutshell: poisoned and a
poisonous mess.

Re: Worse RoHS Madness



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**Of course. Lead poisoning is a possible explanation for his particular
pathology. I suspect he takes no precautions against lead poisoning when he
shoots or loads his own amunition.


--
Trevor Wilson
www.rageaudio.com.au



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Shit, when I was a kid, I used to melt down a kilo or more of lead on
the kitchen stove to play with. Dunno if it affected my brain, but if it
did, I must've been meant to be an uber-genius...


--
    W
  . | ,. w ,   "Some people are alive only because
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