http://www.guardian.co.uk/technology...ch.engineering

Within a whisker of failure

Removing lead from solder may seem a smart idea environmentally, but the
resulting microscopic growths called tin whiskers could be just as
problematic

* Kurt Jacobsen
* The Guardian,
* Thursday April 3 2008
* Article history

This article appeared in the Guardian on Thursday April 03 2008 on p1 of the
Technology news & features section. It was last updated at 00:05 on April 03
2008.
Tin whiskers

On April 17 2005, the Millstone nuclear generating plant in Connecticut shut
down when a circuit board monitoring a steam pressure line short-circuited.
In 2006, a huge batch of Swatch watches, made by the eponymous Swiss
company, were recalled at an estimated cost of $1bn (£500m). In both cases,
"tin whiskers" - microscopic growths of the metal from soldering points on a
circuit board - were blamed for causing the problems.

It's not the first time these mysterious growths have been blamed for
electronics failures. In 1998 the Galaxy IV communications satellite
sputtered out after just five years; engineers diagnosed its failure as due
to "whiskers".

The US military blamed them for malfunctioning F-15 radar systems and
misguided Phoenix and Patriot missiles. In 1986, the US Food and Drug
Administration recalled a number of pacemakers because of these same
whiskers. In fact, they've been known about since the 1940s, and happen with
cadmium and zinc, too: during the second world war, similar whiskers would
short the cadmium tuning capacitors in aircraft radios. A decade later,
tin-based relays in AT&T telephone switching centres were found to cause
shorts.


The solution to "whiskering"? Mix lead into the solder, as was done from the
1950s. Colin Hughes, a physicist who worked on the first British nuclear
bomb, told me that the whiskering problem never came up during his career.

But now the lead is gone, by legal mandate, and whiskers are back - causing
potential problems for us all.

Since 2006, lead has been banned from solder in the European Union under the
2003 Reduction of Hazardous Substance (RoHS) directive, which gave
manufacturers three years to phase out lead.

The logic seemed reasonable. Removing lead from petrol (where it was used to
prevent engine mistiming) brought clear environmental and health benefits,
taking a harmful chemical that can affect intelligence out of the
atmosphere. Removing lead from solder, the 37% lead, 63% tin alloy used to
join metal objects in everything from plumbing to circuit boards, was an
obvious next step to prevent it leaching into ground water from dumped items
in landfills.

Meanwhile, the US and Japan have also been moving to lead-free solders. It's
a huge shift; the US Environmental Protection Agency (EPA) estimates that
80m kilograms of lead solder was used worldwide in 2002. Environmental
groups have applauded the move. "In the US we've been surviving without lead
solder for many years," says Rick Hind, legislative director of Greenpeace's
toxics campaign. "With less exposure to lead we will all benefit by being
smarter and making safer and more durable products." (The US has not made
lead-free solder obligatory, but does offer tax benefits for doing so.)

But without lead to tame it, tin behaves oddly on circuit boards. Left
alone, tin plating, like cadmium and zinc, spontaneously generates
microscopic shreds of metal - about one to five microns in diameter, or less
than one-tenth as wide as a human hair - which push up from the base. If
they grow far enough to touch another current-carrying location, they'll
cause a short that can wreck the equipment while leaving barely any trace.

The cause is becoming clearer. "I believe the mechanism of whisker formation
is now understood: it is due to compressive stress - caused by, say,
diffusion of copper into the tin - being built up in the tin layer which
breaks through the tin oxide barrier layer [to the air]," says Steve Jones
of Circatex, in South Shields. Critics cite reports that solder
substitutes - pure tin, tin-zinc, tin-silver-copper - simply cannot match
the lead mixture for reliability, coverage ("wetting" terminals), and cost
(silver is especially pricey). Therefore, the US military, Nasa and medical
and high-level research equipment are exempt from what authorities view as
untrustworthy commercial components.

"I still use lead-tin solder - it works better," says John Ketterson, a
solid state physicist at Northwestern University in Illinois. He notes the
tradeoffs of "cost, materials, strength of the solder and all that" during
this mandated changeover, and that manufacturers "have to get an experience
base" with new processes.

{ snipped as lengthy }

Tin whiskers: coming to a PC near you?

· They can grow at ambient temperature and humidity, or in vacuum

· They can grow in steady or varying temperatures (though the latter may
encourage growth)

· Whiskers' tips are atom-sharp. They will push through any coating, given
time

· They are a prevalent cause, only now being identified, of many past
equipment failures

· One whisker can carry about 30mA - more than enough to cause havoc in
digital circuits

· Silver-tin-copper ("SAC") solder slows but doesn't stop whisker growth

· SAC solder has more environmental impact than the lead-tin version

· Older 37%-63% lead-tin solder mix merely deforms, reducing stress and
hence minimising whiskering

· Whiskers can grow indefinitely

Source: Howard Johnson, Signal Consulting

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

The logic seemed reasonable. Removing lead from petrol (where it was used
to
prevent engine mistiming) brought clear environmental and health benefits,
taking a harmful chemical that can affect intelligence out of the
atmosphere. Removing lead from solder, the 37% lead, 63% tin alloy used to
join metal objects in everything from plumbing to circuit boards, was an
obvious next step to prevent it leaching into ground water from dumped
items
in landfills.

Meanwhile, the US and Japan have also been moving to lead-free solders.
It's
a huge shift; the US Environmental Protection Agency (EPA) estimates that
80m kilograms of lead solder was used worldwide in 2002.


Isn't it funny how figures can be 'distorted' to make facts suit the
context. By saying "80m kilos", the EPA make it sound like a HUGE amount,
but put that into a more 'recognisable' form, and it becomes 80 thousand
tonnes, which is not nearly so contentious. Then further, take that only 37%
of that was actually lead, and you are down to 29.6 thousand tonnes. Now
compare that to the world's lead-acid battery usage, where recycling of the
end-of-life product to recover the lead, has been sucessfully in place for
years. At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

As I've said before, I'm glad that the avionics industry refuse to use the
stuff. The day they do is the day I stop flying ...

Arfa

On Thu, 03 Apr 2008 09:10:10 GMT, Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first place?

Jonesy

Allodoxaphobia wrote:
Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore,
which I think is much less of a health hazard than metallic lead
decomposing in a landfill and seeping into the water supply.

In Europe, there are places where the Romans smelted lead 2000
years ago, and 8" or so below the topsoil, the dirt is still so
toxic that health officials (in Britain at least) don't allow
people to dig there, even wearing protective gear.

BTW, I'm not a pinhead, just someone who cares about my health,
that of others and a quality environment for us to all live in.

I tried lead-free solder, and gave up on it, at least for prototyping.
I was feeling a little bad about returning to traditional solder,
until the OP posted the article. Thanks - I feel vindicated. I hope
that someday there is a better alternative to lead-based solder,
but evidently it hasn't happened yet.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

Jay Ts wrote:


In Europe, there are places where the Romans smelted lead 2000
years ago, and 8" or so below the topsoil, the dirt is still so
toxic that health officials (in Britain at least) don't allow
people to dig there, even wearing protective gear.

Welcome to California.


I tried lead-free solder, and gave up on it, at least for prototyping.
I was feeling a little bad about returning to traditional solder,
until the OP posted the article. Thanks - I feel vindicated. I hope
that someday there is a better alternative to lead-based solder,
but evidently it hasn't happened yet.

I've used 'alternative' solder. I could live with it if need be. It
handles differently but geez, I think the fumes would kill me faster
than eating a pound of lead solder everyday at tea. I've never heard
the proponents addressing the wicked fumes of the 'better' solder.

-Bill (63/37)

--
Posted via a free Usenet account from http://www.teranews.com

On Apr 3, 6:00*pm, exray wrote:
Jay Ts wrote:
snip
I've used 'alternative' solder. *I could live with it if need be.
*It
handles differently but geez, I think the fumes would kill me
faster
than eating a pound of lead solder everyday at tea. *I've never
heard
the proponents addressing the wicked fumes of the 'better' solder.

-Bill (63/37)


You mean the fumes from the flux. You don't believe you're breathing
solder vapors, do you? In the 40+ years I've been using solder, I
doubt I've used 5 lbs and I do quite a bit of soldering.

GG

"Jay Ts" wrote in message
g.com...
Allodoxaphobia wrote:
Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore,
which I think is much less of a health hazard than metallic lead
decomposing in a landfill and seeping into the water supply.

In Europe, there are places where the Romans smelted lead 2000
years ago, and 8" or so below the topsoil, the dirt is still so
toxic that health officials (in Britain at least) don't allow
people to dig there, even wearing protective gear.

BTW, I'm not a pinhead, just someone who cares about my health,
that of others and a quality environment for us to all live in.

I tried lead-free solder, and gave up on it, at least for prototyping.
I was feeling a little bad about returning to traditional solder,
until the OP posted the article. Thanks - I feel vindicated. I hope
that someday there is a better alternative to lead-based solder,
but evidently it hasn't happened yet.

Jay Ts


Basically, there isn't a lead-free alternative that works the same, or even
close, but you're missing the point(s). Firstly, there isn't *quite* such a
huge amount or disposal problem as they would have you believe. Second, the
lead in solder is pretty firmly 'locked into' the alloy, such that it
doesn't readily come out of the solder into water. Yes, I know that acid
rain can have some effect on that equation, but that's nothing like as bad
as it once was. Finally, all electronic equipment in Europe at least, is now
subject to the WEEE directive, which dictates the way it is treated at end
of life, covering recycling and disposal of the remains that can't be
recycled. There is no reason at all that leaded solder could not be
recovered and recycled, in the same way as lead free solder. 80% of the
world's metallic lead production goes to automotive battery manufacture.
Lead recovery and reuse from that product at end of life, has been mandated
and successfully carried out, for years.

I think that this is the reason that most people who have to use lead-free,
get so wound up about it. As far as I am concerned, the legislation that
mandates its use, is ill-considered, not thought through, unnnecessary in
the light of the legitimate WEEE directive, and effectively replaces a
mature and reliable technology, with one that has the potential to be
directly dangerous to human life, if it ever finds its way into avionics,
medical, and military applications, which so far, have managed to secure
exemptions.

Like any sensible person, I don't want to deliberately pollute the planet
for those who come after me, but in recent years, many badly informed
decicisions on this sort of thing, have been made by departments 'jumping on
the banwagon' to justify their own existence. The whole thing isn't helped
by celebrities and ex famous politicians serving their own public eye needs
through 'green' issues. It has actually reached the point where I am now
sick to death of hearing the words "green" and "eco" and "carbon footprint"
and "geenhouse gas" and "cimate change" and "global warming" every single
time I turn on the radio or TV. So here's a new word.

Eco********. Covers what a lot of this bull actually is ...

Arfa

Like any sensible person, I don't want to deliberately pollute
the planet for those who come after me, but in recent years,
many badly informed decicisions on this sort of thing, have
been made by departments "jumping on the banwagon" to
justify their own existence.

Instead of banning polluting substances, we should be regulating the
pollution they create.

In other words, it doesn't matter how much of a harmful substance you use in
manufacturing a product, but how much of it gets into the environment. It's
the latter we should be worried about, not the former.

Arfa Daily wrote:

snip

It has actually reached the point where I am now
sick to death of hearing the words "green" and "eco" and "carbon footprint"
and "geenhouse gas" and "cimate change" and "global warming" every single
time I turn on the radio or TV. So here's a new word.

Eco********. Covers what a lot of this bull actually is ...

Sentiment seconded.

Message sorted headers by date from my nntp provider:

Lead free solder - exposed in a UK national newspaper Arfa Daily
Lead Generation Computer Systems liukaiyuan
....

I expected to see an advert for cpus soldered with 63/36 or 60/40

Michael

Arfa Daily wrote:
"Jay Ts" wrote in message
g.com...

Allodoxaphobia wrote:

Arfa Daily wrote:


At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore,
which I think is much less of a health hazard than metallic lead
decomposing in a landfill and seeping into the water supply.

In Europe, there are places where the Romans smelted lead 2000
years ago, and 8" or so below the topsoil, the dirt is still so
toxic that health officials (in Britain at least) don't allow
people to dig there, even wearing protective gear.

BTW, I'm not a pinhead, just someone who cares about my health,
that of others and a quality environment for us to all live in.

I tried lead-free solder, and gave up on it, at least for prototyping.
I was feeling a little bad about returning to traditional solder,
until the OP posted the article. Thanks - I feel vindicated. I hope
that someday there is a better alternative to lead-based solder,
but evidently it hasn't happened yet.

Jay Ts



Basically, there isn't a lead-free alternative that works the same, or even
close, but you're missing the point(s). Firstly, there isn't *quite* such a
huge amount or disposal problem as they would have you believe. Second, the
lead in solder is pretty firmly 'locked into' the alloy, such that it
doesn't readily come out of the solder into water. Yes, I know that acid
rain can have some effect on that equation, but that's nothing like as bad
as it once was. Finally, all electronic equipment in Europe at least, is now
subject to the WEEE directive, which dictates the way it is treated at end
of life, covering recycling and disposal of the remains that can't be
recycled. There is no reason at all that leaded solder could not be
recovered and recycled, in the same way as lead free solder. 80% of the
world's metallic lead production goes to automotive battery manufacture.
Lead recovery and reuse from that product at end of life, has been mandated
and successfully carried out, for years.

I think that this is the reason that most people who have to use lead-free,
get so wound up about it. As far as I am concerned, the legislation that
mandates its use, is ill-considered, not thought through, unnnecessary in
the light of the legitimate WEEE directive, and effectively replaces a
mature and reliable technology, with one that has the potential to be
directly dangerous to human life, if it ever finds its way into avionics,
medical, and military applications, which so far, have managed to secure
exemptions.

Like any sensible person, I don't want to deliberately pollute the planet
for those who come after me, but in recent years, many badly informed
decicisions on this sort of thing, have been made by departments 'jumping on
the banwagon' to justify their own existence. The whole thing isn't helped
by celebrities and ex famous politicians serving their own public eye needs
through 'green' issues. It has actually reached the point where I am now
sick to death of hearing the words "green" and "eco" and "carbon footprint"
and "geenhouse gas" and "cimate change" and "global warming" every single
time I turn on the radio or TV. So here's a new word.

Eco********. Covers what a lot of this bull actually is ...

Arfa


Try tin/silver, *no* copper.
Nice shiny (sexy looking?) surfaces, easy to solder, have seen no
problems in 2 years where circuits get a lot of temperature cycling.

Arfa Daily wrote:
....
Basically, there isn't a lead-free alternative that works the same, or even
close, but you're missing the point(s). Firstly, there isn't *quite* such a
huge amount or disposal problem as they would have you believe. Second, the
lead in solder is pretty firmly 'locked into' the alloy, such that it
doesn't readily come out of the solder into water. Yes, I know that acid
rain can have some effect on that equation, but that's nothing like as bad
as it once was. Finally, all electronic equipment in Europe at least, is now
subject to the WEEE directive, which dictates the way it is treated at end
of life, covering recycling and disposal of the remains that can't be
recycled. There is no reason at all that leaded solder could not be
recovered and recycled, in the same way as lead free solder. 80% of the
world's metallic lead production goes to automotive battery manufacture.
Lead recovery and reuse from that product at end of life, has been mandated
and successfully carried out, for years.
...

All this being obviously true, it is inconceivable that the ROHS thing
has been done out of sheer stupidity - noone is that stupid, even
though
those in high offices routinely want to look that in order to be left
alone.
I can think of no plausible explanation for this ROHS madness
other than a well planned and executed sabotage action agaist the
countries which have (and rely on) an electronics industry. At a
scale that large, even the most expensive to bribe officials cost
peanuts.

Dimiter

------------------------------------------------------
Dimiter Popoff Transgalactic Instruments

http://www.tgi-sci.com
------------------------------------------------------
http://www.flickr.com/photos/didi_tg...7600228621276/

Original message: http://groups.google.com/group/sci.e...b?dmode=source

In article m,
says...
Allodoxaphobia wrote:
Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore,
which I think is much less of a health hazard than metallic lead
decomposing in a landfill and seeping into the water supply.
Mettalic lead has been shown to have very little impact on the
environment. Especially after it has built up an oxide layer.


In Europe, there are places where the Romans smelted lead 2000
years ago, and 8" or so below the topsoil, the dirt is still so
toxic that health officials (in Britain at least) don't allow
people to dig there, even wearing protective gear.
Ah, but we aren't talking about running a smelting operation, are we?


BTW, I'm not a pinhead, just someone who cares about my health,
that of others and a quality environment for us to all live in.
I don't know.
Comparing burying metallic lead VS a smelting operation, that borders on
pinheadiness.


I tried lead-free solder, and gave up on it, at least for prototyping.
I was feeling a little bad about returning to traditional solder,
until the OP posted the article. Thanks - I feel vindicated. I hope
that someday there is a better alternative to lead-based solder,
but evidently it hasn't happened yet.

Jay Ts


Until they come up with better alternatives, I'll stick with good old
lead/tin. When I left my last job, I had a full physical including a
lead test, and even though I had been "exposed" to lead solder almost
daily for 13 years, my blood lead levels were almost not measurable and
that puts me below the national average for people that don't work with
solder at all. Why would that be if lead/tin solder were so dangerous?

Jim

"James Beck" wrote in message
th.net...
In article m,
says...
Allodoxaphobia wrote:
Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore,
which I think is much less of a health hazard than metallic lead
decomposing in a landfill and seeping into the water supply.
Mettalic lead has been shown to have very little impact on the
environment. Especially after it has built up an oxide layer.


In Europe, there are places where the Romans smelted lead 2000
years ago, and 8" or so below the topsoil, the dirt is still so
toxic that health officials (in Britain at least) don't allow
people to dig there, even wearing protective gear.
Ah, but we aren't talking about running a smelting operation, are we?


BTW, I'm not a pinhead, just someone who cares about my health,
that of others and a quality environment for us to all live in.
I don't know.
Comparing burying metallic lead VS a smelting operation, that borders on
pinheadiness.


I tried lead-free solder, and gave up on it, at least for prototyping.
I was feeling a little bad about returning to traditional solder,
until the OP posted the article. Thanks - I feel vindicated. I hope
that someday there is a better alternative to lead-based solder,
but evidently it hasn't happened yet.

Jay Ts


Until they come up with better alternatives, I'll stick with good old
lead/tin. When I left my last job, I had a full physical including a
lead test, and even though I had been "exposed" to lead solder almost
daily for 13 years, my blood lead levels were almost not measurable and
that puts me below the national average for people that don't work with
solder at all. Why would that be if lead/tin solder were so dangerous?

Jim

Unfortunately, if you are professionally involved in the repair of
electronic equipment in Europe, continuing to use leaded solder, unless the
equipment was placed on the market prior to June 2006 or is manufactured in
leaded solder now due to an exemption, is no longer a legal option. I am
required under threat of law, to use only solder and components, which
preserve the RoHS approval of the equipment in question. I don't suppose
realistically, that any 'solder police' are going to come knocking on my
door to enforce this, but with some of the jobsworths that there are in
local government departments now, it's just not worth the risk of a whopping
fine and even the potential for prison, for disobeying the directive.

Arfa

James Beck wrote:
In article m,
says...
Allodoxaphobia wrote:
Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore, which I
think is much less of a health hazard than metallic lead decomposing in
a landfill and seeping into the water supply.
Mettalic lead has been shown to have very little impact on the
environment. Especially after it has built up an oxide layer.

In Europe, there are places where the Romans smelted lead 2000 years
ago, and 8" or so below the topsoil, the dirt is still so toxic that
health officials (in Britain at least) don't allow people to dig there,
even wearing protective gear.
Ah, but we aren't talking about running a smelting operation, are we?

Not if you can get all your lead from recycled materials,
and won't have to dig up any more ore and process it.

Otherwise, we have to look at the entire process.
That's just good engineering.

BTW, I'm not a pinhead, just someone who cares about my health, that of
others and a quality environment for us to all live in.
I don't know.
Comparing burying metallic lead VS a smelting operation, that borders on
pinheadiness.

Maybe we go on different definitions. To me, "pinhead" refers
more to people who have very pointed, narrow ways of thinking,
and foolishly fail to choose wisely in regards to the big picture.

When I left my last job, I had a full physical including a
lead test, and even though I had been "exposed" to lead solder almost
daily for 13 years, my blood lead levels were almost not measurable and
that puts me below the national average for people that don't work with
solder at all. Why would that be if lead/tin solder were so dangerous?

Easy one! Blood tests often fail to show up heavy metal toxicity.
You shouldn't expect them to, because the problem with heavy
metals is that they build up in body tissues, not the blood.
That's exactly the problem! They hang around in the body,
building up in and causing problems with vital organs (e.g.,
liver, colon, brain, bones) and *don't* easily dissolve out
in the blood and get flushed out.

The blood test may be good for cases of extreme (acute)
toxicity. I suppose that's why the doctors have them.
They like to get credit for saving lives. But there
is also chronic low- to moderate-level heavy metal
poisoning. It is bad too.

Don't expect an allopathic doctor to help you discern
heavy metal toxicity. They are too busy putting them *in*
your body while avoiding lawsuits to be of much assistance.

If you want a good test for heavy metals, you need to use other
methods. The one I'm most aware of is using a small sample
of hair. Removing bits of liver, bone or brain aren't really
practical, so this is the only method I know that's practical
and that naturopathic practitioners seem to prefer.

I've actually never heard of anyone having that test done
and finding out they had an issue with lead. Usually, its
cadmium or mercury. In my area, arsenic and copper are a
problem. That is a result from a local copper mine that was
very active about 100 years ago. The processing of the ore
put a lot of arsenic and copper in the environment, and it's
been leaching into the local water supply. This is in the
middle of a huge national forest, where you'd think the
water would be not as bad. Maybe that has something to
do with my concern for the effects of mining and processing.

The people who ran the mine probably had no idea at all
this would ever happen. Instead of being more concerned,
they just shrugged it off and did what made them the quickest
money. I think a more careful and conservative approach is
prudent. Sometimes, "better safe than sorry" applies.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

Jay Ts wrote:

It came from deep within the ground, in the form of lead ore,
which I think is much less of a health hazard than metallic lead
decomposing in a landfill and seeping into the water supply.

In Europe, there are places where the Romans smelted lead 2000
years ago, and 8" or so below the topsoil, the dirt is still so
toxic that health officials (in Britain at least) don't allow
people to dig there, even wearing protective gear.


The slag they skimmed of wile refining the lead is what is toxic, not
the lead. Those compounds already existed. They were just mixed up in
the ore.


--
aioe.org is home to cowards and terrorists

Add this line to your news proxy nfilter.dat file
* drop Path:*aioe.org!not-for-mail to drop all aioe.org traffic.

http://improve-usenet.org/index.html

Jay Ts wrote:

Allodoxaphobia wrote:
Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore,
which I think is much less of a health hazard than metallic lead
decomposing in a landfill and seeping into the water supply.

Lead is an element, it is composed of lead and can't decompose. It is so
soluble that water pipes and roofs are made out of it......
--

nospam wrote:
Jay Ts wrote:

Allodoxaphobia wrote:
Arfa Daily wrote:

At 30th tonnes, the potential environmental impact of the lead in
solder, even if you *did* dump it all in the ground, is minuscule.

And, where do these pin-heads think the lead came from, in the first
place?

It came from deep within the ground, in the form of lead ore, which I
think is much less of a health hazard than metallic lead decomposing in
a landfill and seeping into the water supply.

By this I meant that if it's deeper than groundwater, there's
a nearly zero chance of it getting into the water, or being a
problem in any other way.

Also, I had run into some information about lead toxicity several
years ago that said that naturally-occurring lead compounds are
not as much a problem as artificial (industrial) ones, because
living beings are evolved to handle the "organic" (I think it
was orthophosphate, but am not sure) form of lead, and can more
easily flush it out of the body, preventing bioaccumulation.
I tried just now to find that info again, but couldn't.

Lead is an element, it is composed of lead and can't decompose. It is so
soluble that water pipes and roofs are made out of it......

Lead is an element, it is a toxic element, and it can react chemcially
to make toxic compounds. It can corrode when exposed to water,
and the corrosion by-products are soluble enough that lead found
in drinking water comes mostly from the lead in pipes and solder
used to hold the pipes together.

References:
http://www.epa.gov/ebtpages/pollairpolead.html
http://www.epa.gov/lead/
http://www.epa.gov/ttn/atw/hlthef/lead.html
http://www.epa.gov/safewater/dwh/t-ioc/lead.html

I went to the EPA site and did a search on "lead" because it
became clear to me from previous discussion here that I really
didn't know enough about lead toxicity to write at my usual
level of knowledge. As I've said, I know more about other,
more toxic, heavy metals, and lead has not been of big concern
to me.

What I read at the EPA's site confirmed that there isn't much
cause for concern with regards to the lead in solder. They
say that although there is cause for concern, lead doesn't
have as great a bioaccumulation factor as other heavy metals.
And they didn't say anything at all about electronic solder
or people who work with it, so it looks like those who said
they got blood tests that showed no problem are justified
to feel they are ok. (If it were me, and maybe it is, I'd
still get the test done that uses a hair sample, just to
make sure.)

Most of the fuss in the past was about lead-based paint and
lead from car exhaust. Both of those have been phased out.
(Although recently there have been problems with lead paint
being used on toys made in China.)

The EPA hardly mentioned solder at all. As far as I could
find, only with regards to water pipe and tin cans (where
it is also no longer used).

Looks like I was right about the lead smelting operations,
though. And wouldn't you know it, most of that is done in
the general region of the planet in which I live (SW USA).
By far, most of the lead in use is for car batteries,
so I don't see any need to give up leaded solder just
for that.

In the Wikipedia article for "solder", it is said that
smoke from solder flux can contain a little lead oxide,
and that the flux smoke itself can be toxic. So I'll be
a little more careful to have good ventilation while
soldering. Pretty simple!

Although the EPA noted that metallic lead does corrode,
resulting in toxic soluble compounds, they didn't say anywhere
(at least that I could find) that lead in landfills is
considered a significant problem, and there was no mention
of danger from tossing used electronics in the trash.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

N_Cook wrote:

http://www.guardian.co.uk/technology...ch.engineering

Within a whisker of failure

About time too.

Never mind the reduced reliability (see the ERA study) caused by lead-free
solder when equipment is exposed to vibration.

Graham

"Eeyore" wrote in message ...


N_Cook wrote:

http://www.guardian.co.uk/technology...ch.engineering

Within a whisker of failure

About time too.

Never mind the reduced reliability (see the ERA study) caused by lead-free
solder when equipment is exposed to vibration.

Graham

Its good for the way economy works nowadays. Buy, buy, buy the crap
that dies or obsoletes every 2-3 years.

Mark

TheM wrote:
"Eeyore" wrote in message ...


N_Cook wrote:


http://www.guardian.co.uk/technology...ch.engineering

Within a whisker of failure

About time too.

Never mind the reduced reliability (see the ERA study) caused by lead-free
solder when equipment is exposed to vibration.

Graham


Its good for the way economy works nowadays. Buy, buy, buy the crap
that dies or obsoletes every 2-3 years.

Mark


Absolutely; we are in the replace crap with crap "economy".

Eeyore wrote in message
...


N_Cook wrote:

http://www.guardian.co.uk/technology...ch.engineering

Within a whisker of failure

About time too.

Never mind the reduced reliability (see the ERA study) caused by lead-free
solder when equipment is exposed to vibration.

Graham


Before I waste time downloading an irrelevant pdf

would this be what you be referring to :

Review of Directive 2002/95/EC (RoHS) Categories 8 and 9 - Final

http://ec.europa.eu/environment/wast...nal_report.pdf

Results of vibration testing lead-free solder from different researchers ...


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

N_Cook wrote:

Eeyore wrote
N_Cook wrote:

http://www.guardian.co.uk/technology...ch.engineering

Within a whisker of failure

About time too.

Never mind the reduced reliability (see the ERA study) caused by lead-free
solder when equipment is exposed to vibration.


Before I waste time downloading an irrelevant pdf

would this be what you be referring to :

Review of Directive 2002/95/EC (RoHS) Categories 8 and 9 - Final

http://ec.europa.eu/environment/wast...nal_report.pdf

Results of vibration testing lead-free solder from different researchers ...

Not sure if that's the one I had to be honest but looks interesting.

Graham

Eeyore wrote in message
...


N_Cook wrote:

Eeyore wrote
N_Cook wrote:


http://www.guardian.co.uk/technology...ch.engineering

Within a whisker of failure

About time too.

Never mind the reduced reliability (see the ERA study) caused by
lead-free
solder when equipment is exposed to vibration.


Before I waste time downloading an irrelevant pdf

would this be what you be referring to :

Review of Directive 2002/95/EC (RoHS) Categories 8 and 9 - Final

http://ec.europa.eu/environment/wast...nal_report.pdf

Results of vibration testing lead-free solder from different researchers
....

Not sure if that's the one I had to be honest but looks interesting.

Graham


One small bit from that study

"Solder joint failure due to vibration becomes more significant as the
frequency of vibration approaches the resonant frequency of the component or
structure.
Studies by Chuang et al 29 and
Song et al 30 have sought to identify microstructural features that
influence the performance of conventional Sn-Pb solders and candidate
replacement lead-fre solders. The typical microstructure of conventional
Sn-Pb solders containing coarse pro-eutectic grains reduces the ability of
these materials to absorb energy during crack formation and hence reduces
the vibration resistance of joints made using these solders. "

I thoutht distributed irregularities in structures, suppressed crack
propogation.
Would seem NOT to be borne out for the case for premature failures of solder
joints for unsupported dropper resistors in mucic combos - ie amplifiers
contained within the same case as large speaker/s.
Failure in 2 or 3 years of routine use wheras more like 20 years for failure
in similar but older PbSn manufacture.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

As I've said before... It isn't a matter of whether electronic equipment has
lead in it, but what happens to that equipment when it's disposed of. It's
the latter that should be considered.

"William Sommerwerck" wrote in message
. ..
As I've said before... It isn't a matter of whether electronic equipment
has
lead in it, but what happens to that equipment when it's disposed of. It's
the latter that should be considered.




And lead isn't the only toxic substance used in electronic equipment and the
process used to manufacture it.

Is a lead-free item that fails and ends up in the landfill after 2 years
better than a lead-containing device that lasts a decade?

"James Sweet" wrote in message
news:HOfJj.5873$yd2.3213@trndny04...


"William Sommerwerck" wrote in message
. ..
As I've said before... It isn't a matter of whether electronic equipment
has
lead in it, but what happens to that equipment when it's disposed of.
It's
the latter that should be considered.




And lead isn't the only toxic substance used in electronic equipment and
the process used to manufacture it.

Is a lead-free item that fails and ends up in the landfill after 2 years
better than a lead-containing device that lasts a decade?

And is then properly recycled ?

Arfa

William Sommerwerck wrote:

As I've said before... It isn't a matter of whether electronic equipment has
lead in it, but what happens to that equipment when it's disposed of. It's
the latter that should be considered.

AIUI, lead in metallic form is pretty stable and doesn't 'leach' into
groundwater the way some would have us believe.

Graham

William Sommerwerck wrote:
As I've said before... It isn't a matter of whether electronic equipment
has lead in it, but what happens to that equipment when it's disposed
of. It's the latter that should be considered.

There's the other end of the process too: mining, smelting,
and the rest of the manufacturing process that might be producing
pollution. All that is outside my realm of knowledge. Maybe they
do it in an "environmentally-friendly" manner these days? I really
have no idea.

I think ideally, we'd find something better to use, but although
it's gotten a lot of bad press, there are much worse things than
lead. Such as other heavy metals, notably cadmium and mercury.

Another source of lead is CRTs, many of which are still in use.
They contain about 5 pounds of lead each for radiation protection,
quite a bit more than is contained in the solder in the PC boards.

And the replacements, flat screen monitors, have mercury in
the fluorescent backlights.

I've had trouble with mercury poisoning in the past, but even
though I'd been exposed to a lot of lead as a child, I've never
discerned any problem from it. (It's tricky though, low- to
moderate-level heavy metal poisoning can easily go unnoticed,
while causing significant health problems.)

This does not mean that solder-containing lead is "good",
just that it's appropriate to keep things in perspective.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

"Jay *******"

Another source of lead is CRTs, many of which are still in use.
They contain about 5 pounds of lead each for radiation protection,
quite a bit more than is contained in the solder in the PC boards.



** Silly comparison.

Glass does not break down in the environment.

So how would any of that lead get out ??



....... Phil

On 04 Apr 2008 03:42:35 GMT, Jay Ts
wrote:

Another source of lead is CRTs, many of which are still in use.
They contain about 5 pounds of lead each for radiation protection,
quite a bit more than is contained in the solder in the PC boards.

And the replacements, flat screen monitors, have mercury in
the fluorescent backlights.

If you've ever seen the size of a fluorescent backlight for an LCD
you'd realise that scrapping even a few hundred of them produces three
fifths of seven sixteenths of bugger all mercury.


--

one reply got into print

* The Guardian,
* Thursday April 10 2008

Getting the lead out

Thank you for publishing the article on tin whiskers (Within a whisker of
failure, April 3). Too much attention has been given to well-meaning people
who are pushing the environmental agenda but with very little science behind
what they are trying to achieve. Some of the green community captured the
public attention and pushed through the no lead on electronics, when there
was not sufficient test data available (actually there was a lot of data on
US military aircraft). Now we are finding the problems of having a political
agenda and not one based on science and facts.
Steven Adamson, IMAPS president and Asymtek market manager


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

"N_Cook" wrote in message
...
one reply got into print

* The Guardian,
* Thursday April 10 2008

Getting the lead out

Thank you for publishing the article on tin whiskers (Within a whisker of
failure, April 3). Too much attention has been given to well-meaning
people
who are pushing the environmental agenda but with very little science
behind
what they are trying to achieve. Some of the green community captured the
public attention and pushed through the no lead on electronics, when there
was not sufficient test data available (actually there was a lot of data
on
US military aircraft). Now we are finding the problems of having a
political
agenda and not one based on science and facts.
Steven Adamson, IMAPS president and Asymtek market manager


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/



Very nicely put by Mr Adamson and, whilst The Guardian is not one of my
favourite rags, all credit to them for at least publishing a reply that
swims against the tide, and does not tow the government line ... It's good
to see some 'alternative' views finally making themselves heard in the
public domain !

Arfa

more printed followup
http://www.guardian.co.uk/technology/2008/apr/17/1
# The Guardian,
# Thursday April 17 2008
Tin woes solder on

Congratulations on the very interesting article on tin whiskers (Within a
whisker of failure, April 3). You may be interested to hear of another
phenomenon associated with lead-free solders in electronics, known as tin
pest. Research was carried out into the allotropy of tin 80 years ago. Tin
pest was found to occur by a process of nucleation and growth of "grey" tin
(a form found below 13C), and was very slow - often requiring years to
complete. Since the transition from "white" to "grey" tin involved a 27%
increase in volume, its formation was restricted to the surface. Recently,
tin pest has been reported in bulk samples of lead-free solder alloys
following a few years' exposure at -18C, the usual freezer temperature.

To date it has not been observed on actual joints. But lead-free
interconnections have been in service for a relatively short time. Although
we do not know whether it is necessary to shut the stable door, we should
make more effort to understand and control tin pest formation. Only time
will tell whether it represents a real problem in electronics.
Professor Bill Plumbridge
Faculty of Technology
The Open University



--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

"N_Cook" wrote in message
...
more printed followup
http://www.guardian.co.uk/technology/2008/apr/17/1
# The Guardian,
# Thursday April 17 2008
Tin woes solder on

Congratulations on the very interesting article on tin whiskers (Within a
whisker of failure, April 3). You may be interested to hear of another
phenomenon associated with lead-free solders in electronics, known as tin
pest. Research was carried out into the allotropy of tin 80 years ago. Tin
pest was found to occur by a process of nucleation and growth of "grey"
tin
(a form found below 13C), and was very slow - often requiring years to
complete. Since the transition from "white" to "grey" tin involved a 27%
increase in volume, its formation was restricted to the surface. Recently,
tin pest has been reported in bulk samples of lead-free solder alloys
following a few years' exposure at -18C, the usual freezer temperature.

To date it has not been observed on actual joints. But lead-free
interconnections have been in service for a relatively short time.
Although
we do not know whether it is necessary to shut the stable door, we should
make more effort to understand and control tin pest formation. Only time
will tell whether it represents a real problem in electronics.
Professor Bill Plumbridge
Faculty of Technology
The Open University



--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/



'Plumb' -ridge. What an appropriate name for someone versed in lead matters
! Seriously though, I'm really glad that the scientific establishment is
finally making some anti lead-free noise, and backing up with genuine
science, what we lowly service engineers have been trying to tell the world,
since the first day that this hateful material was foisted on us by self
serving bureaucrats with a politically 'green' agenda ...

Arfa

and some balancing comment
http://www.guardian.co.uk/technology/2008/apr/24/2
# The Guardian,
# Thursday April 24 2008
A whisker of doubt

I believe there are several inaccuracies in Kurt Jacobsen's article (Within
a whisker of failure, April 3). He cites the Swatch watch company as
recalling a "huge batch" of watches that amounted to a financial loss, when
in fact Swatch was denied its request for a RoHS exemption, as another
supplier makes lead-free quartz movements it could use with no whisker
issues. Also, Swatch makes no mention of a recall in its EU request. The
nuclear power plant failure example and others are also misleading, as these
were failures due to pure-tin formulations that predate RoHS. The new
formulations reduce these issues. Here's a good article that refutes the
"gloom and doom" predictions: tinyurl.com/4wxmkz.
Marcus England, by email


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

"N_Cook" wrote in message
...
and some balancing comment
http://www.guardian.co.uk/technology/2008/apr/24/2
# The Guardian,
# Thursday April 24 2008
A whisker of doubt

I believe there are several inaccuracies in Kurt Jacobsen's article
(Within
a whisker of failure, April 3). He cites the Swatch watch company as
recalling a "huge batch" of watches that amounted to a financial loss,
when
in fact Swatch was denied its request for a RoHS exemption, as another
supplier makes lead-free quartz movements it could use with no whisker
issues. Also, Swatch makes no mention of a recall in its EU request. The
nuclear power plant failure example and others are also misleading, as
these
were failures due to pure-tin formulations that predate RoHS. The new
formulations reduce these issues. Here's a good article that refutes the
"gloom and doom" predictions: tinyurl.com/4wxmkz.
Marcus England, by email


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/



Hmmm. Have you ever come across any solder that's pure tin ? It would take a
blowtorch to melt it. Also, there is plenty of research that shows that the
lead in tin-lead solder alloy, mitigates the growth of tin whiskers, whereas
copper doesn't. And anyway, none of the whisker issues alter the fact that
the bloody stuff just doesn't make reliable joints on many component forms,
as anyone involved at the sharp end, would attest to ...

The article that Mr England cites, does not instil a great deal more
confidence in me. Whilst it may be true that *some* cellular phones have
been manufactured in lead-free since 2001, this 'fact' tells us nothing
about the long-term reliability of them, as most are owned primarily as a
fashion statement - even amongst 'mature' businessmen - and only
secondarily as a communications device. This, as well as the fact that the
battery only lasts a short while, dictates that it is replaced on a yearly
basis, which is encouraged by the cellular operators, when they give the
latest all singing and dancing models away, as an incentive to stick with
their network.

Further, this is just one single low power device, As all of us involved in
electronic service work know, there are many other consumer devices such as
TV sets, DVD players, HiFi, microwave ovens etc which, unlike cellphones,
contain large power components and connectors, which do not enjoy good long
term - or often even short term - reliability, when jointed using lead-free
solders. This in no way supports the statement in the article that :-

"This field data indicates the reliability of lead-free assemblies is equal
to, or better than, tin-lead soldered assemblies".

You simply can't make statements like that based on a single product group,
and claim them to have blanket validity.

The further statement ....

"While laboratory studies suggest lead-free solder does not perform as well
in high-stress applications, such as might occur in a ‘drop test', many
applications with these types of concerns (i.e. military) are currently
exempted from RoHS. Meanwhile, alloy developmental work to address lead-free
shortcomings is already underway."

..... contains three areas of concern in that (1) lead-free solder does not
perform *as well* ... (2) some applications e.g. military have concerns
about this, and (3) that it is accepted that the technology has shortcomings
that need to be addressed.

Further, I also have a problem with the first paragraph in the article :-

"Most people incorrectly think the primary intent of RoHS is to protect the
environment. In truth, the fundamental purpose of RoHS is to make recycling
EEE easier and safer."

Protection of the environment was the ticket on which RoHS in general - and
this substitute lead-free technology in particular - was originally sold to
an unsuspecting world. It seems to me that those who make up this
eco-legislation (as they go along, I suspect) are now discovering the error
of their original concept as to why the mature and proven lead solder
technology needed replacing, and are now seeking to bury that error in a
different concept altogether. I can't remember ever before seeing any
reference anywhere to RoHS being primarily to improve the ease and safety of
WEEE recycling, rather than as an environmental issue.

So, far from this article "refuting the gloom and doom", I think it serves
only to further highlight the well known shortcomings of lead-free solder
technology, and unfortunately for Mr England's case, I don't believe that
his letter holds a candle to the two from the other side of the coin, which
preceded it.

Arfa

Arfa Daily wrote in message
...

"N_Cook" wrote in message
...
and some balancing comment
http://www.guardian.co.uk/technology/2008/apr/24/2
# The Guardian,
# Thursday April 24 2008
A whisker of doubt

Protection of the environment was the ticket on which RoHS in general -
and
this substitute lead-free technology in particular - was originally sold
to
an unsuspecting world. It seems to me that those who make up this
eco-legislation (as they go along, I suspect) are now discovering the
error
of their original concept as to why the mature and proven lead solder
technology needed replacing, and are now seeking to bury that error in a
different concept altogether. I can't remember ever before seeing any
reference anywhere to RoHS being primarily to improve the ease and safety
of
WEEE recycling, rather than as an environmental issue.

So, far from this article "refuting the gloom and doom", I think it serves
only to further highlight the well known shortcomings of lead-free solder
technology, and unfortunately for Mr England's case, I don't believe that
his letter holds a candle to the two from the other side of the coin,
which
preceded it.

Arfa



What exactly can be recycled from say a PC?
As far as I can see the steel casing and perhaps some copper if it is not
too widely distributed , fragmented, needing human separation and plastic
separation environmental problems.
RoHS for recycling implies component level recycling - recycling 3 to 10
year old pc ICs - pull the other one.
Failing that, recycling processed sand and hard plastic after desoldering,
very unlikely. Leaves just the solder itself, which is just as recyclable
with or without lead presumably .

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/