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Worse RoHS Madness

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:

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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:

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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 -

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An interesting comparison:

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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

Reply to
Phil Allison
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"Phil Allison"

** See section 6 in the pdf file. :

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.... Phil

Reply to
Phil Allison

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

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

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and this one:

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

regards Terry

Reply to
Terry Dawson

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.

Reply to
Mr.T

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

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Clint Sharp
Reply to
Clint Sharp

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
   \\|/  \\|/     it is illegal to kill them."    Perna condita delenda est
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Reply to
Bob Larter

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

Reply to
Terry Dawson

In message , Terry Dawson writes

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.

Excuse my ignorance, is a sport shooter a target shooter?

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Clint Sharp
Reply to
Clint Sharp

**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. 
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Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

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

Reply to
Mark Harriss

**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. 
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Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

dont they use stainless steel pellets now ?? mark

Reply to
mark krawczuk

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