ROHS calculation for leaded solder on circuit boards
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1. Aluminum
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## ROHS calculation for leaded solder on circuit boards

We use leaded solder for the components on the circuit board that controls our product. I'm not sure how the lead limits (1000 ppm for ROHS) are calculated. I assume it's on a component basis so you would look at how much lead was in the solder. But by chance is it calculated by taking the weight of the lead in the solder and dividing by the weight of the whole product (about 50 lbs)?

We easily pass if it's the second option but I'm guessing it's the first option.

2. Hot Rolled
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I thought that the ppm measurement applied to the lead free solder itself?

https://assets.publishing.service.go...ance-notes.pdf

3. Reading the document is interesting. There are a number of exemptions.

EEE intended to protect national security and/or for military purposes
Products where electricity is not the main power source
Products where the electrical or electronic components are not needed to fulfil the primary function
Electrical and electronic equipment that is part of another type of equipment

The last one has an interesting example:

Examples of such equipment would be lighting or entertainment equipment for use in vehicles, trains or aircraft. This type of equipment would be excluded as it is designed to be part of a product that falls outside the scope of the Directive

It looks like machine tools could be exempt:

To large-scale stationary industrial tools. (This is a machine or system, consisting of a combination of equipment, systems, products and/or components installed by professionals, each of which is designed, manufactured and intended to be used only in fixed industrial applications.)

I think this is what would affect the OP(my bold):

For the purposes of the RoHS Regulations, a maximum concentration value of up to 0.1% by weight in homogeneous materials for lead, mercury, hexavalent chromium, PBB and PBDE.

Page 16 has a decision tree.

The exceptions are interesting as well. There's a metals exemption for lead:

6. Lead as an alloying element in steel containing up to 0.35% lead by weight, aluminium containing up to 0.4% lead by weight and as a copper alloy containing up to 4% lead by weight

12L14 shows .15 to .35 in the source I consulted, so it would be OK. The exemptions are very interesting.

Please remember all this is just some guy on the internet......

4. Titanium
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Just got an email from a customer and the last 4 items are new and I need to certify that my products are "safe" with lower than the limits. I do not know what they are so can I say they are not in the plastic parts of the components that I sell? I do not even know what the 2 items above the 4 new ones are. GRRR!!
"As you probably know in July of this year there will be additional elements added to the list of Restricted Substances for RoHS compliance … (phthalates)

Will your company and your suppliers be compliant with new regulations? All suppliers to XXX XXXXXXXX will be required to provide new RoHS Certificates after these changes are in affect."

This is the complete list of Restricted Substances: highlighted in yellow are the elements being added.
New List of Restricted Substances

Substance Name

Limit (%)

Mercury 0.1%

Hexavalent chromium 0.1%

Polybrominated biphenyls (PBB)0.1%

Polybrominated diphenyl ethers (PBDE)0.1%

Bis(2-ethylhexyl) phthalate (DEHP)0.1%

Butyl benzyl phthalate (BBP)0.1%

Dibutyl phthalate (DBP)0.1%

Diisobutyl phthalate (DIBP)0.1%

5. Hot Rolled
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Originally Posted by FredC
Just got an email from a customer and the last 4 items are new and I need to certify that my products are "safe" with lower than the limits. I do not know what they are so can I say they are not in the plastic parts of the components that I sell? I do not even know what the 2 items above the 4 new ones are. GRRR!!
"As you probably know in July of this year there will be additional elements added to the list of Restricted Substances for RoHS compliance … (phthalates)

They are used as plasticisers.

Phthalates Factsheet | National Biomonitoring Program | CDC

6. Titanium
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I recently had to provide a conflict minerals statement to a customer to machine their own material.

Buyers understand this stuff even less than we do. So they apply it to everything whether it was meant to apply or not.

@FredC- those phthalates coule easily be in plastic parts, you will need a RoHS statement from the supplier.

7. Titanium
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My understanding, not having dealt with it personally is that lead free solder is pretty much a mandate for EU.

If one does not have a specific reason to use lead solder, I would think avoiding
[shuffles over to hide spool of 60/40 across from computer] it would be the idea

seriously I think the goal is prectically zero lead, is pretty attainable, and they are probably going to reject anything lead soldered

8. Hot Rolled
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Originally Posted by gustafson
My understanding, not having dealt with it personally is that lead free solder is pretty much a mandate for EU.

If one does not have a specific reason to use lead solder, I would think avoiding
[shuffles over to hide spool of 60/40 across from computer] it would be the idea

seriously I think the goal is prectically zero lead, is pretty attainable, and they are probably going to reject anything lead soldered

That is how I see it unless the equipment is exempt in some way.

And the OP reference to 1000 ppm for
ROHS I'm sure refers to the solder used, and not lead content in the whole circuit board?

9. Aluminum
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Thanks for all the replies - the paper was very good.

I am convinced that it is the lead in the solder (not the lead in the entire product) that needs to be held to 1000 ppm or less. The paper uses the term "homogeneous".

There may be an opening for us in the covered and exempt listings. We make portable electric winches. I actually found a paper online from a firm that argued that winches and cranes were exempt from ROHS.

As for the solder, years ago we tried using the lead free solder but had problems. It was probably our method more than anything. At the time we said the heck with it - just stay with the easy to use leaded stuff. Looks like we're going to have to revisit the use of the lead free solder.

10. Titanium
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Originally Posted by BobM3
Thanks for all the replies - the paper was very good.

I am convinced that it is the lead in the solder (not the lead in the entire product) that needs to be held to 1000 ppm or less. The paper uses the term "homogeneous".

There may be an opening for us in the covered and exempt listings. We make portable electric winches. I actually found a paper online from a firm that argued that winches and cranes were exempt from ROHS.

As for the solder, years ago we tried using the lead free solder but had problems. It was probably our method more than anything. At the time we said the heck with it - just stay with the easy to use leaded stuff. Looks like we're going to have to revisit the use of the lead free solder.
Since the winches are safety related and failure of a soldered joint could cause death or injury you might have a good case for continuing to use leaded solder. If not there have been a lot of advances in lead free solder over the last few years, I make parts for the electronics industry and hear a lot less complaints now than when the change was instituted. Sorry for hijacking your thread before you got to a conclusion.
Thanks for the 2 that helped on my question. I copied and pasted a request to one of my suppliers.

11. Aluminum
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That's a good point about it being a safety issue - I may point that out to McMaster-Carr (the company that needs the info from me).