A Phantom Menace?
BILL BUSHER, Skeptical Briefs, June 2005
Let's start with a fable.
A decree goes forth from the European Union based on the belief that Earth is flat. E.U. member states are not convinced
by scientific evidence to the contrary. Of course, most legislators, being lifetime politicians and little schooled in the
scientific method, think
this a most wise decision. After all, even if they are
wrong, what harm can it do to change a few maps?
The United States, being
somewhat more enlightened, opts for a wait-and-see attitude. After all, even if the Europeans are right, what could happen?
A few careless travelers might fall off the edge of the world, but even a cursory examination of the evidence shows that
Earth had been, and probably still is, round. In an effort to educate the masses, seminars, courses, and conferences
are held. Not one seminar agenda, not one course syllabus, and not any of the conferences containing contrary to this
politically safe but scientifically unsound path. Eventually, the populace becomes convinced that Earth is flat. The dangers
of falling off the edge of Earth are cause enough to warrant legislation prohibiting travel to the edge of the world.
And it is made so.
A brief bit of background
information is necessary to understand the point of that fable. We all enjoy the benefits of modern technology. Computers,
global-positioning devices, cell phones, satellite radio, and even intelligent refrigerators have become commonplace.
They are manifestations of constantly evolving technologies that not so long ago gave us crystal radio sets and telephone
switchboard systems. Modern or primitive, all of these devices are made up of components such as resistors, transistors,
and more recently, integrated circuits such as those that provide computer memory. The "glue" that holds them together is
solder. An alloy of tin/lead has been found to have the optimum mechanical and thermal properties to act as a conductive,
permanent bond. It is plentiful, cheap to produce, and reliable.
In June 2000, the European
Union passed restrictive legislation known as the RoHS (Restriction of Hazardous Substances) Directive. The largest impact this directive and associated legislation will
have is to ban the use of lead in electronic products by July 1, 2006. This includes electronics imported into the E.U. On
the surface, this seems like a good idea. One only has to conjure up images of little tykes chewing on chips of lead-based
paint and the resultant toxic effects to understand the motives behind such an effort. Who would argue against limiting
that exposure? After all, the Latin word for lead, plumbum, is the root of the medical term for lead poisoning: plumbism.
At the risk of being called
an anti-environmentalist, I submit that the manufacturers of electronic circuit boards and the associated industries
are being moved (a better verb might be dragged) in a direction that makes little sense. The positive effects on the
environment will be negligible to nonexistent, while the industry's costs for redesign, revalidation, fabrication, assembly,
and rework will be immense, all in the name of political correctness and bad science.
Consider the following: Yearly lead usage in electronics
in the U.S. accounts for around 0.5 percent of total usage, while ammunition accounts for 5 percent and car batteries top
the list at over 80 percent, according to the IPC (Institute for Printed Circuits), an association, based in the United
States, that deals with electronics issues. According to the IPC, the ban on
lead usage in electronics is entirely European. No similar legislation is pending or has been proposed in the United States.
The amount of lead that leaches into groundwater from
electronics-industry waste is negligible. Some studies suggest that silver and antimony may pose more of a threat than lead
in landfills, since these materials are more soluble under certain groundwater conditions.[i] The replacements for tin-lead solder
alloys (the most common of which is a silver-tin-copper mix) have not been shown to be any less toxic.[ii]
The military, wary that the
incidence of "tin whiskers" (hair-like crystal structures that grow from tin-coated surfaces and are known to cause electrical
failures) may increase, is resisting the use of lead-free solder but may ultimately have no choice but to change, given
the diminishing availability of leaded materials.[iii]
Assembled circuit boards need
to be soldered. They are sent through a conveyer-like transport system into a chamber containing a bath of molten solder.
The boards skim over the surface of the pool, which results in the connections on the underside being soldered. These
"wave solder machines" as they are called, use energy, and lots of it. Amkor, a manufacturing resource for many semiconductor
companies, says that the temperatures at which the replacement solders melt is approximately 37 degrees Celsius higher
than for leaded solders. Multiply this by the thousands of machines in use worldwide, and you can have an appreciation for
the upward surge in energy usage.
Still not convinced it's a
bad idea? There are many industry experts that are very worried about the fact that the new alloys do not form joints
as strong as leaded alloys. Recent investigations have revealed that lead-free solder joints may be fragile and prone to premature
interfacial failure, particularly under sudden stress.[iv] This may mean very poor reliability and lower yields. Lower reliability sounds like an
abstract notion best left to the engineers to deal with, until your cell phone goes dead or your car doesn't start. The effects
of higher fabrication temperatures on devices not necessarily designed (or tested) to withstand the higher temperatures
will have an impact on design, procurement, testing, and reliability of those items.
A 1997 study by the National Center for Manufacturing Sciences estimated the cost
of no-lead solder to the U.S. electronics industry to be in the tens of billions of dollars.[v] This and other associated costs will
no doubt be passed on in some measure to consumers. Unfortunately, the consumer may make matters worse. When purchasing,
for example, a new DVD player (if prices and features are similar), which one do you think most people would buy? Would it
be the one
with the "green" sticker proclaiming, "Does not contain lead"? Remember that the only way to get lead poisoning is through
ingestion. Mull over that fact the next time you are taking sips of wine from your expensive leaded crystal. But since the ban doesn't take effect until mid-2006, this won't have any effect on us for a while, right?
Wrong: some cell phones and other products (Sony Playstations, for example) are being produced with non-lead-based solder
right now. Intel, Texas Instruments, and other manufacturers of myriad "pieces/parts" that go into electronic devices, such
as memory chips, microprocessors, resistors, and capacitors, have already started to fabricate and sell parts that contain
the lead-free solders. Recent surveys indicate that only about 60 percent will be compliant by the deadline. Even though the
ban is European in origin, not even American companies that sell products only domestically will be immune, as the manufacture
of parts and processes worldwide continues to convert to the use of lead-free solder.
By now (hopefully),
you are starting to ponder the question: "Why?" The IPC vigorously (and successfully) fought U.S. legislation to
ban leaded solder in 1992. IPC President Dennis McGuirk said, "the. IPC . . . recognizes that there are no data indicating
environmental or health hazards posed by lead in printed wiring board manufacturing and electronics assembly." Nevertheless,
the official IPC position, issued in 1999, reads, in part: "IPC prefers global rather than regional solutions to this issue,
and is encouraging a coordinated approach to the voluntary reduction or elimination of lead by the electronic interconnection
industry.” The premise was that the ban was an ill-conceived overreaction to a non-problem, and it is. Why then is the industry being encouraged to keep diverting energy and money into lead
elimination when end-of-life recycling improvements would be much more beneficial?
There are exemptions in the
ban. Joe Fjelstad, an international authority and innovator in the field of electronic interconnection, states that "The
absurdity in the lead-ban effort is the number of exemptions there are for lead (e.g., 93.5% of all lead uses are exempted,
while lead in electronic solder represents less than 0.5% of all lead used)."[vi] And
lead-free solder is not the same as lead-
free electronics. The vast majority of the lead used
in a computer is found in the tube envelope inside the monitor—as much as 2.59 pounds, according to the World Semiconductor
Council.[vii] Ironically, the monitor is exempted from the ban, due to the lack of a viable alternative.
Computer servers and telecommunications are also not covered. It may be instructive to note that those are considered high-reliability
applications. Does this uncover uncertainties on the part of legislators regarding possible degradation of those products?
What can we expect from those applications considered lower on the reliability food chain, i.e., products you and I are more
likely to purchase?
Banning lead in solder is unscientific political
correctness at its worst. Preying on the fears of an environmentally
jittery but well-meaning public, it will cost the electronics industry and consumers dearly while reducing the overall
reliability of the products. Lead-free solder simply does not work as well as the leaded version. Scientific data documenting
the harmful effects of lead content in electronics has not been clearly established. No case has ever been documented
of lead poisoning resulting from solder in electronics.
Production lines will
slow down, due to increased process times more inspections, and yield problems. (For example, since
lead-free solder joints differ from tin-lead in appearance, quality
guidelines for visual inspection will require modification.). Costs will rise
due to issues such as more expensive materials (silver instead of lead) and increased mining costs. All of this begs the question:
Why replace a perfectly good material that has virtually no effect on the environment, that is cheap, plentiful, and a proven
performer, and that is being recycled in large quantities now, with problem alloys that require much more energy to process?
I don't know either.
Busher is a. quality systems engineer
working for INFICON in East Syracuse, N.Y., a manufacturer of high-tech process monitoring and control instrumentation.
He is a two-time chair of the Syracuse Section of the American Society for Quality, Immediate Past President of the Technology
Alliance of Central New York, and will soon serve as the president of Central New York Skeptics.
[i] Pb-Free.com. Frequently asked questions.
[ii] Edwin B. Smith and L. Kristine Swanger. Lead fret- solders: A push in the wrong direction. K-Tec
[iii] The Boeing Company. 2002. Boeing Environmental
[iv] Peter Borgeson and Donald W. Henderson. 2004. Fragility of
Pb-free solder joints. Universal Instruments.
[v] Circuitnet. 2004. Technology news. November.
[vi] Joseph Fjelstad. 2002. The death of common sense. CircuiTree.
[vii] World Semiconductor Council. 2001. Lead free white paper.