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Elementary, Mr. Watson: Responsible PCB Design Must Go Beyond RoHS

[Warning: This column may feel like getting a shot; it's going to hurt a bit, but it is necessary.]

Remember the advice that Uncle Ben gave Peter Parker in “Spiderman?” "With great power comes great responsibility," he said, meaning that if you can do something, make sure it is for the good of others.

In the field of PCB design, a massive paradox exists. No doubt, the PCB industry is a fascinating field. The ever-changing design environment faces constant and more complex challenges to make products smaller, faster, and cheaper. There are endless ways that electronic innovation changes lives for the better, as seen when advanced medical systems provide patients a new lease on life. But there also is a downside, an unfortunate side, to PCB design, and it has bothered me for some time. There is a massive amount of new PCB products hitting the market, especially in the consumer marketplace. But what happens to the "obsolete" products that are discarded, known as e-waste? This dark side of the PCB industry is not spoken about in social circles, but with innovation comes some negative.

The World Economic Forum reported in 2021 that e-waste, such as discarded TVs, computers, peripherals (i.e., printers, scanners, and fax machines), mice, keyboards, and cellphones totaled about 57.4 million metric tons—and it continues to increase. One metric ton is equal to 2,206 pounds. To put this into perspective, total annual e-waste outweighs the Great Wall of China.

About 151 million cellphones end up in landfills annually in the United States alone, reflecting U.S. consumers' insatiable appetite for “the latest and greatest.” We need to change this paradigm that electronics are disposable. These mounds of e-waste contain high amounts of precious metals—nearly 35,274 pounds of copper, 772 pounds of silver, 75 pounds of gold, and 33 pounds of palladium—which is equal to more than $60 million in gold and silver alone. There’s reportedly more precious metals in e-waste than in metals unearthed by the most productive mines.

Furthermore, the touchscreens in these cellphones contain indium and tin oxide. Most of the glass in LCD screens is a mixture of alumina, silica, potassium, and small amounts of mercury. The problem is even worse with batteries, which, when disposed incorrectly, contaminate the earth, water, and air with their harmful toxic chemicals.

When laying out a PCB design, we should consider how these harmful things may ultimately impact the environment. In his classic play “Death of a Salesman,” Arthur Miller wrote that our desire "to leave a thumbprint somewhere on the world is a need greater than hunger or thirst.” We PCB designers may improve people's lives through innovation, but what "fingerprint" are we leaving behind in the world? Are we, as a nation, leaving a thumbprint that causes more harm than good?

Turning the Tide
Many organizations are noticing these grim statistics and the growing problem of e-waste. One of the early leaders in this area was the Basel Convention in 1989, which developed an international treaty prohibiting developed countries from transporting various types of hazardous waste, including e-waste, to less developed countries. Although the United States signed this agreement, it is the only developed country that has not ratified this treaty, which means we do not abide by its rules and regulations. According to United Nations estimates, the United States exports up to 40% or 23 million metric tons of its e-waste to undeveloped countries, even though they are less able than us to handle such an overwhelming problem. Why send harmful toxic chemicals and materials offshore on a vast scale when it can cause unbelievable harm, especially to underdeveloped countries? The answer: So we don’t have to deal with it. Out of sight, out of mind.

We all are familiar with Restriction of Hazardous Substances (RoHS), which was adopted by the European Union in February 2003. The original regulation focused on removing about ten hazardous materials, including the “big three,” lead, mercury, and cadmium. The initiative prompted the entire industry to develop better and safer ways to manufacture PCB. Since then, RoHS or RoHS 1 has expanded to RoHS 2. The law, which took effect in January 2013, extends to  four new substances:

• Bis(2-Ethylhexyl) phthalate (DEHP)
• Benzyl butyl phthalate (BBP)
• Dibutyl phthalate (DBP)
• Diisobutyl phthalate (DIBP)

I believe that this is a good start. But statistically speaking, we are still not keeping up with the tide of e-waste hitting our own landfills or, even worse, being sent to undeveloped countries. 

Next Steps
I would be amiss if I did not consider what we PCB designers can do about this problem. The PCB processes, the materials used, and the physics even with a simple PCB, is very well documented and established. As we saw with RoHS 1 and the elimination of lead, any changes in that process can significantly impact the fabrication and assembly process. It is easy to assume that further changes or restrictions will have the same outcome. So, our first step is to know what we can and cannot change, but we must sustain the precarious balance between design performance and manufacturability. 
 
It is a good sign that e-waste is gaining grass-roots or community-level attention. That is a great start, but we must do more to turn the tide. Becoming aware of this problem and opening dialog will quickly change how everyone works together to leave “good” fingerprints around the world, including underdeveloped countries. Our rallying cry in the PCB industry should echo, "With great power comes great responsibility." Our responsibility is to leave behind something better.

John Watson, CID, is a customer success manager at Altium.

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