Conformity Magazine - December 2007 - (Page 24) any potential distributor mix-ups (accidents can happen), and will provide a secondary verification of the manufacturer’s certifications. Don Kennedy, the Chief Engineer at Pulizzi Engineering, Inc., a division of Eaton Corporation, notes that “many certifications for components and materials are very general, aren’t based on actual lot test results, aren’t traceable to specific manufacturing or material lots, and are therefore not reliable. We’ve found that XRF scanning of receiving inspection samples has been much more effective in preventing non-conforming materials from making their way into our products.” In one manufacturing environment, the results of the XRF scanning were surprising. At least 25% of the RoHS certifications which accompanied the incoming parts were invalid because the parts failed this critical inspection step. The suppliers claimed to have documented compliance from their vendors, and suggested that the inspection process was at fault. To back up the in-house quality control department, the manufacturer committed money for a number of independent inspections by outside labs, which did indeed verify the internal scans. Based on this experience, it’s easy to see why a company’s purchasing department needs to be represented on the RoHS conformity committee, as questions can arise over whether to reject all or partial amounts of the incoming material, or possibly to accept the entire lot. It is necessary to be flexible and interactive with suppliers to help them transition to the RoHS restrictions and compliance processes. Incoming material that is destined for RoHS-compliant products should be so marked and kept separate until pulled for the RoHSdedicated assembly line. This physical separation prevents components from entering and contaminating the lead free circuit board manufacturing process. Then, the assembled product should be subjected to a thorough final RoHS compliance check before being marked as “RoHS Certified” and shipped to the customer. To conform to the RoHS regulations, the “Certificates of Compliance” (verifiable, written statements of assurance that any material or components do not contain any amounts of the proscribed elements above the allowable limits) must be retained for a minimum of four years. As the RoHS limitations apply to the total amount of these materials, statistics on the cumulative amounts must be generated and maintained, since it is not the percentage of hazardous material related to the total product weight but the percentage of these materials in any physically separable element of the shippable unit. These records must be readily accessible so that it is easy to provide the totals for each end item. Additionally, the recordkeeping database must include a sufficiently robust inventory control protocol to keep noncompliant components from accidentally entering a product which will be RoHS-certified. This may require a complete rework of a company’s part numbering/inventory system to assure that RoHS-compliant elements do not possess the same part numbers as previously purchased non-compliant parts. Conclusion Conformity with the RoHS Directive is difficult and more costly than “non-green” manufacturing protocols, but is rewarded not only by benefits to the planet, but the ability to trumpet ones “green” product as against the negative publicity which could be generated by your RoHS-compliant competitors. The investment is huge, both in financial and human terms, but if you plan on staying in business during this movement to more environmentally friendly products and manufacturing, it is going to be necessary to actively and diligently pursue these RoHS conformance issues and regulations. Roger Edelson is a senior technical staff writer with Pulizzi Engineering, Inc., a division of Eaton Corporation, and can be reached at rogharv@comcast.net. FAST Link www.conformity.com/1240 24 Conformity DeCember 2007 http://directory.conformity.com http://www.conformity.com/1240
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