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Not familiar with the reasons why the lead ban or rohs would be an issue for the environment, can you point me in the right direction? They seem like positive m

by verelo 7y ago

Not familiar with the reasons why the lead ban or rohs would be an issue for the environment, can you point me in the right direction? They seem like positive moves on the surface, but I’m sure they’re not as straightforward as I’d like.

userbinator 7y ago
One of the reasons: https://en.wikipedia.org/wiki/Whisker_(metallurgy) https://en.wikipedia.org/wiki/Whisker_(metallurgy) Lead-free solder is also less resilient to thermal stress because it's not as ductile, and that lead to plenty of PCB failures around the time manufacturers switched over --- creating even more e-waste. Fortunately, military/aerospace is still exempt from the ban. Here's an interesting NASA presentation about lead-free vs. leaded solder: https://nepp.nasa.gov/whisker/reference/tech_papers/2011-kostic-Pb-free.pdf https://nepp.nasa.gov/whisker/reference/tech_papers/2011-kos...
- hedora 7y ago
  The problems from lead-free solder are mostly solved, though avoiding them is non-trivial, and does require special expertise.
- qiqitori 7y ago
  Ah, so your argument is that the lead ban has led to PCB defects that might have increased e-waste. Let't think about e-waste for a bit. Let's say you have a PCB that you do not need anymore. This PCB is made of the following materials: - mostly epoxy - surface mount components: ceramics, plastics, glass, etc. - metals such as tin, copper, steel, aluminum, gold Generally, only the metal bits are worth recovering, everything else needs to be burned. (It's possible to burn epoxy and other plastics without producing harmful gases.) Depending on the type of board, the metals may or may not be worth recovering. If it's just tin and steel and copper, there's no harm in just shredding and burning the whole thing. (After shredding, a small amount of metal may recovered by magnets and routed to the foundries.) If the burning is done correctly (and it definitely isn't if you do this on the streets somewhere), no harmful gases are produced, and materials like ceramics, glass and metals will be left in the ash/slag. (BTW, even if your incineration facility sucks somehow and harmful gases like dioxins are produced, most of these decompose from UV exposure.) That slag will often be used to build roads, and e.g. this company says they're able to refine the slag a bit: https://www.adrecyclingmachines.com/applications/incineration-slag https://www.adrecyclingmachines.com/applications/incineratio... Now, what if there's lead or other heavy metals in that slag? You probably would want to avoid using that for road construction, and since metals form alloys, you'll also be able to recover a whole lot less reusable metal. Lead has really, really bad effects on human health (not just cancer, but generic insanity). Most people seem to think that lead causes cancer, along with thousands of other compounds. But when they're told that lead causes insanity, they usually tend to listen a bit more carefully. If "insanity" doesn't mean much to you... Well, there have been studies correlating lead exposure with violent crimes. (* I haven't read these studies, but they can be found on Google)

by verelo 7y ago

userbinator 7y ago

One of the reasons: https://en.wikipedia.org/wiki/Whisker_(metallurgy) https://en.wikipedia.org/wiki/Whisker_(metallurgy) Lead-free solder is also less resilient to thermal stress because it's not as ductile, and that lead to plenty of PCB failures around the time manufacturers switched over --- creating even more e-waste. Fortunately, military/aerospace is still exempt from the ban. Here's an interesting NASA presentation about lead-free vs. leaded solder: https://nepp.nasa.gov/whisker/reference/tech_papers/2011-kostic-Pb-free.pdf https://nepp.nasa.gov/whisker/reference/tech_papers/2011-kos...

hedora 7y ago
The problems from lead-free solder are mostly solved, though avoiding them is non-trivial, and does require special expertise.
qiqitori 7y ago
Ah, so your argument is that the lead ban has led to PCB defects that might have increased e-waste. Let't think about e-waste for a bit. Let's say you have a PCB that you do not need anymore. This PCB is made of the following materials: - mostly epoxy - surface mount components: ceramics, plastics, glass, etc. - metals such as tin, copper, steel, aluminum, gold Generally, only the metal bits are worth recovering, everything else needs to be burned. (It's possible to burn epoxy and other plastics without producing harmful gases.) Depending on the type of board, the metals may or may not be worth recovering. If it's just tin and steel and copper, there's no harm in just shredding and burning the whole thing. (After shredding, a small amount of metal may recovered by magnets and routed to the foundries.) If the burning is done correctly (and it definitely isn't if you do this on the streets somewhere), no harmful gases are produced, and materials like ceramics, glass and metals will be left in the ash/slag. (BTW, even if your incineration facility sucks somehow and harmful gases like dioxins are produced, most of these decompose from UV exposure.) That slag will often be used to build roads, and e.g. this company says they're able to refine the slag a bit: https://www.adrecyclingmachines.com/applications/incineration-slag https://www.adrecyclingmachines.com/applications/incineratio... Now, what if there's lead or other heavy metals in that slag? You probably would want to avoid using that for road construction, and since metals form alloys, you'll also be able to recover a whole lot less reusable metal. Lead has really, really bad effects on human health (not just cancer, but generic insanity). Most people seem to think that lead causes cancer, along with thousands of other compounds. But when they're told that lead causes insanity, they usually tend to listen a bit more carefully. If "insanity" doesn't mean much to you... Well, there have been studies correlating lead exposure with violent crimes. (* I haven't read these studies, but they can be found on Google)