Why Most Static Programs Fail
For many years, electronics companies have invested in static-preventive wrist straps, bins, bags, table mats, and ionizers—all in the hopes of eliminating electrostatic discharge.
What did these firms get for their money?
Some organizations realized immediate improvements—both in yield and in reduction of field returns. Others simply found an ESD program necessary for successful solicitation and retention of contracts. Many are not sure just what they got and worse, why they got it. ESD has been recognized as a threat to electronic devices since the introduction of blasting caps and detonators to the mining industry. Numerous technical articles, awareness seminars, and preventive products are readily accessible to industry. The cause, effect, and solution to ESD is widely accepted and well documented. Why, then, is it so difficult for engineers to convince management to provide the funds essential for establishing an in-house static program? Many times, ESD-control programs do not measure up to the anticipated objectives, or even more disheartening, are completely ineffective. To a wide extent, these programs never really had a fighting chance; they were doomed from inception. A major manufacturer of computer peripherals was quite proud of its ESD program and was not shy to point out its considerable expenditure. However, an audit became necessary when the new gate arrays used in a recently introduced product were failing at an astounding rate. Also, field returns were eating away at profits and at a hard-earned reputation. A thorough investigation of the situation uncovered numerous broken links in a chain of protection dependent upon total continuity.
The audit confirmed that the use of wrist straps, conductive containers, dissipative table mats, and ionizers were in compliance with the guidelines set by the manufacturer’s prospective customers. However, half of the wrist straps failed a simple continuity test, and many of those that did pass were either connected improperly or worn too loosely to ground the wearer reliably. The table tops, installed by the bench manufacturer, were grounded without the mandatory one mega ohm resistor in line. When questioned about ESD training, most assembly people commented that they recalled viewing “some film about zaps and zings.” The ionizer blowers contained enough dust and dirt to allow only a whisper of the original air flow to pass through them. The tote boxes, originally supplied with lids, were being utilized uncovered because the lids were cumbersome and did not appear to serve any purpose beyond that of dust collector. The incident described is not an isolated circumstance. It is not uncommon for manufacturers to feel that the success or failure of an ESD program is based on the amount of money invested. What they often do not realize is that for any ESD program to be successful, there are a number of factors that need to be addressed prior to implementation. If obstacles are recognized in advance and cannot be resolved, the project should not be undertaken. In most cases though, the obstacles that lead to failure can be avoided, sometimes before a single nickel is wasted.
The Eight Most Common Reasons Why ESD Programs Fail
Little support from top management
Most engineers seek management’s support before soliciting capital funding for a project. However, the appropriation of funding should be the tip of the iceberg when it comes to management’s role in the development of a successful ESD program. The most common reason for the failure of ESD programs is the lack of visible support by top management. Management needs to show, by example, that everyone— CEO and customers included—must exercise the precautions specified by the static expert. Furthermore, management should be prepared to show support by appearing at training seminars and by giving a brief preliminary pep-talk relating the features and benefits of the ESD program and the impact each individual will have upon it. Management should also praise departments with satisfactory records of ESD prevention and should provide assistance for those departments that fall short of the mark. To be successful, ESD prevention requires teamwork— achieved through consistence and dedication—between all levels of the organization.
The band-aid approach as opposed to a permanent solution
Many ESD programs appear to have been based on the theory that there is never time to do it right, but there is always time to do it over. Many companies, faced with budgetary restraints, employ spot solutions rather than take a long-range look at their options. Examples include the benefits of conductive tile over dirty floor mats, Faraday cage boxes over disposable shielding bags, or permanently installed bench mats over expendable soft table pads. Also, grounds are often installed to the nearest electrical outlet with easily disconnected snaps or low-gauge wire that will break after its first encounter with a tote box. Regardless of the extent of any static program, preventive measures should be installed correctly the first time — when the cost is the lowest. It is far less expensive to static-proof the environment (i.e., the floors, tables, footwear, and material-handling system) than it is to employ and police band-aids that will soon require costly repairs or even replacement.
Poor training or no training at all
Most companies are not prepared to train the entire work force effectively in the “dos and don’ts” of static control. A recent survey of 50 electronics companies found that most training programs required attendees to watch a film about ESD in a crowded room followed only by a brief explanation of the features and benefits of static control. Many of the companies surveyed limited mandatory attendance at training seminars to assembly-level personnel. Effective static control is an all-or-nothing proposition. To thrive (and to provide a payback), the program must be a priority for every employee of a corporation. The CEO can destroy a sensitive component with the same ease as the night janitor. Many dollars are wasted on the purchase of high-quality ESD-prevention equipment that sits in unopened boxes, or worse, is utilized improperly by uneducated or ill-informed personnel. If in-house resources are not able to develop a convincing and informative seminar, then it would be wise to seek outside assistance.
No follow-up after program implementation
Many ESD-prevention items require periodic functional testing, occasional maintenance and, often times, replacement. Employees frequently require further education and positive reinforcement regarding their role in the ESD program. Wrist straps become ineffective from the build-up of insulative skin oils at the point of contact between the wearer’s wrist and the conductive fabric. Unless a continuous testing program is in place, bad wrist straps could be in use for weeks or even months. Static bags wear out and should be replaced. Dirty conductive tables and floors can become insulative, defeating their purpose altogether. The importance of proper maintenance and training reinforcement cannot be overemphasized. The reliability of any ESD program depends upon constant monitoring and fine-tuning where necessary. ESD programs are most successful when one individual is delegated management responsibility. His or her authority must be supported by supervisors and recognized by fellow employees.
Programs implemented only to placate the customer
Quality-conscious organizations and corporations require all suppliers and subcontractors to maintain a static-free environment. The fulfillment of this obligation is usually confirmed by a visit from a vendor engineer. During this visit, the vendor engineer searches for the presence of the static-preventive measures specified by the particular contract. Noncompliance can result in withdrawal of the contract. Short-signed management teams sometimes implement an ESD program purely for the purpose of satisfying a vendor audit. Often, the “solution” is a program hastily installed and comprised of the least expensive materials available. It is not uncommon for these organizations to slap an ESD program together several times a year. Preventive maintenance, follow-up, and training are virtually nonexistent.
At the insistence of those most interested in the elimination of costly throw-away solutions (e.g., the accounting department), the problem is often eventually corrected. A solid understanding of the problem, coupled with the commitment to purchase a long-term solution, is essential to the establishment of a dependable and worthwhile ESD program. In the long run, a well-planned and properly implemented ESD program easily pays for itself through improvements in quality, reliability, and reputation.
Over-reliance on industry standards
It is wise to test any proposed equipment, under in-house factory conditions, regardless of the manufacturer’s compliance with regulatory standards. Before using specifications to compare products, it is imperative to obtain a copy of the standard and to determine the actual parameters of the test. It is important to note that items that behave one way under controlled conditions may perform differently in a factory environment.
Inability to locate a deal with reputable suppliers
The price factor, for many companies, still largely determines the selection of both product and vendor. Little consider ation is given to either the reliability of the vendor or to the range of services that he or she is prepared to supply. At times, even the quality of materials is overlooked in the quest for low-budget solutions. Neglecting to investigate a vendor’s credentials could lead to the downfall of a well intended, albeit cost-controlled program. Reliable vendors can be easily identified by a brief examination of their products and by selective screening of their customer base. Vendors should be prepared to speak knowledgeably on all aspects of the ESD program, including training, maintenance, and calibration.
ESD control is limited to the manufacturing environment
Sensitive electronic parts are most vulnerable to damage in the environment of the end user—the customer. Once outside the manufacturing facility, the components are subjected to static-charge environments. Ill-informed users within these environments are unaware of the thousands of volts of potentially destructive static that they carry on their clothing alone. Despite the hazardous and potentially crippling conditions, the problem remains unrecognized, oftentimes leading to redundant field service calls, excessive downtime, and conceivably, loss of the customer.
The control of ESD is a matter every electronics company must confront. Maintaining the competitive edge in today’s marketplace can hinge on an organization’s ability to deal successfully with the fundamental but elusive phenomenon first recognized by the ancient Greeks over two thousand years ago. The problem, while certainly not insurmountable, demands a formidable opponent in the form of a well-organized, comprehensive static protection program. The successful ESD program depends upon careful planning by conscientious individuals, followed by precise implementation, effective training, and thorough follow-up, originating at the assembly line and progressing straight to the customer.