RoHS: Ask your EMS provider these five questions

By Bruce Calder

So, you have spent considerable effort on converting your products to RoHS compliant. But, you do not build your products. That is the responsibility of your Electronics Manufacturing Services (EMS) provider. For all of your efforts, your products, your sales, and your reputation are dependant on your EMS partner(s).

There are many places that an EMS partner can cause a RoHS non-compliance event that may result in a business interruption for your company.

How do you reduce your risk?

With the push for cost reduction in products and manufacturing processes, many EMS providers are applying leaner measures. Such measures often result in less foresight and less attention to potential issues.

If you do not ask explicitly for RoHS compliance assurance and verification, do not expect it to be completed.

What you need to ask

There is a wide range of questions you could be asking your providers. Questions related to reliability, supply chain, mechanical components, contamination, incoming inspection, surface mount, second-tier suppliers, and inventory management are a few areas to be considered.

But, what are the priority items to discuss?

There are five (5) critical questions to ask your EMS provider. These five questions are by no means an exhaustive list, but are items that should be discussed and will provide a starting point in reducing the risk of interruptions to your business.

Question 1: Will your Pb-free process meet my business needs?

One primary reason an EMS provider is your EMS provider is that he meets your manufacturing needs. Until now, this has generally been based on products using leaded solder. Just because an EMS provider produces acceptable leaded solder products does not mean he will produce acceptable Pb-free products.

The question above is a general question, but there are a number of specific areas of concern.

Recommended areas to investigate include: experience with Pb-free solder, range of board type and board layers processed, processes to prevent Pb contamination and process control, reliability, experience with new board technologies, and cost.

In particular, reliability is a concern; not just for tin whisker growth (which is often the first question in people's minds), but for more standard reliability-related to a significant change in the process.

The risk of early life failure or related issues due to process inexperience have been seen to be a far more significant risk during the transition to Pb-free than the ignominious tin whisker problem.

Question 2: How are you managing your supply chain to ensure my supply chain business continuity?

When a product is converted to RoHS compliant, generally 50 to 70 percent of the internal components are replaced.

How is your EMS provider going to ensure new RoHS-compliant parts are the parts that are placed into the product? What is the EMS provider's inventory policy? How does he handle parts that are only identified as RoHS compliant by the date of manufacture? What procedures has your EMS provider put in place for incoming inspection to ensure that the part requested is the part received?

These may seem like a lot of straight forward questions, but it only takes one part to make a product non-compliant.