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Basics of Electrostatic Discharge
Part Four---Auditing and Training*
Your static control program is up and running. How do you determine whether
it is effective? How do you make sure your employees follow it? Previously,
we suggested that there were at least nine critical elements to successfully
developing and implementing an effective ESD control program. In Part Four,
we will focus on two more of these elements: training and auditing.
Personnel Training
The procedures are in place. The materials are in use.
But, your ESD control program just does not seem to yield the expected results.
Failures declined initially, but they have begun reversing direction. Or perhaps
there was little improvement at all. The solutions might not be apparent in
inspection reports of incoming ESD materials. Nor in the wrist strap log-in
sheets. Sometimes simply turning the pages of the calendar will provide significant
clues. When was the last time your employees attended an ESD training program?
In fact, have your employees been trained at all?
In large companies or small, it is hard to underestimate the role of training
in an ESD control program. There is significant evidence to support the contribution
of training to the success of the program (References 1, 5, 9, 10, 14, 15,
16). We would not send employees to the factory floor without the proper soldering
skills or the knowledge to operate the automated insertion equipment. We should
provide them with the same skill level regarding ESD control procedures.
Elements of Effective Training Programs
Although individual requirements
cause training programs to vary from company to company, there are several
common threads that run through the successful programs.
1 -- Successful training programs cover all affected employees.
Obviously
we train the line employees who test their wrist straps or place finished
products in static protective packaging. But we also include department heads,
upper management, and executive personnel in the process. Typically they are
responsible for the day-to-day supervision and administration of the program
or they provide leadership and support. The training will vary for these different
groups, but awareness and understanding at all levels is key.
2 -- Effective training is comprehensive and consistent.
Training
not only covers specific procedures, but also the physics of the problem and
the benefits of the program as well. Consistent content across various groups,
plants, and even countries (adjusted for cultural differences, of course)
reduces confusion and helps assure conformance.
3 -- Use a variety of training tools and techniques.
Combine
live instruction with training videos or interactive CD-ROM programs. Effective
training involves employees in the process. Reinforce the message with demonstrations
of ESD events and their impact. Bulletin boards, newsletters, and posters
provide additional reminders and reinforcement.
4 -- Test, certify and retrain.
Your training should assure material
retention and emphasize the importance of the effort. If properly implemented,
testing and certification motivates and builds employee pride. Retraining
is an ongoing process that reinforces, reminds, and provides opportunities
for implementing new or improved procedures.
5 -- Feedback, auditing, and measurement.
Motivate and provide
the mechanism for program improvement. Sharing yield or productivity data
with employees demonstrates the effectiveness of the program and of their
efforts. Tracking these same numbers can indicate that it's time for retraining
or whether modifications are required in the training program.
Design and delivery of an effective ESD training program can be just as important
as the procedures and materials used in your ESD control program. A training
program that is built on identifiable and measurable performance goals helps
assure employee understanding, implementation and success.
Auditing
Developing and implementing an ESD control program itself is obvious. What
might not be so obvious is the need to continually review, audit, analyze,
feedback and improve. You will be asked to continually identify the program's
return on investment and to justify the savings realized. Technological changes
will dictate improvements and modifications. Feedback to employees and top
management is essential. Management commitment will need reinforcement.
Like training, regular auditing becomes a key ingredient in the successful
management of ESD control programs. The mere presence of the auditing process
spurs compliance with program procedures. It helps strengthen management's
commitment. Audit reports trigger corrective action and help foster continuous
improvement.
The benefits to be gained from regular auditing of our ESD control procedures
are numerous. They allow us to prevent problems before they occur rather than
always fighting fires. They allow us to readily identify problems and take
corrective action. They identify areas in which our programs may be weak and
provide us with information required for continuous improvement. They allow
us to leverage limited resources effectively. They help us determine when
our employees need to be retrained. They help us improve yields, productivity,
and capacity. And they help us bind our ESD program together into a successful
effort.
An ESD audit measures performance to the defined standards and procedures
of the ESD control program. Typically, we think of an ESD audit as a periodic
review and inspection of the ESD work area covering use of the correct packaging
materials, wearing of wrist straps, following defined procedures, and similar
items. However, a good audit program is a bit more complicated.
Types of Audits
There are several types of ESD audits: the work
place audit, program management audits, and quality process
checking. Each type is distinctively different and each is vitally important
to the success of the ESD program
Program management audits measure how well a program is managed and
how strong management commitment is. The program management audit emphasizes
factors such as the existence of an effective implementation plan, realistic
program requirements, ESD training programs, regular audits, and other critical
factors of program management. The program management audit typically is conducted
by a survey specifically tailored to the factors being reviewed. Because it's
a survey, the audit can be conducted without actually visiting the site. The
results of this audit indirectly measure work place compliance and are particularly
effective as a means of self-assessment for small companies as well as large
global corporations.
Quality process checking applies classical statistical quality control
procedures to the ESD process and is performed by operations personnel. This
is not a periodic audit, but rather daily maintenance of the program. Visual
and electrical checks of the procedures and materials, wrist strap testing
for example, are used to monitor the quality of the ESD control process. Checking
is done on a daily, weekly or monthly basis.
Trend charts and detailed records trigger process adjustments and corrective
action. They help assure that specified procedures are followed on a regular
basis. The records are essential for quality control purposes, corrective
action and compliance with ISO-9000.
Work area audits verify that program procedures are followed and that
ESD control materials and equipment are within specification or are functioning
properly. Audits are performed on a regular basis, often monthly, and utilize
sampling techniques and statistical analysis of the results. The use of detailed
checklists and a single auditor assures that all items are covered and that
the audits are performed consistently over time.
Basic Auditing Instrumentation
Special instrumentation will be required
to conduct work area audits. The specific instrumentation will depend on what
you are trying to measure, the precision you require and the sophistication
of your static control and material evaluation program. However, as a minimum,
you will need an electrostatic field meter, a wide range resistance
meter, a ground/circuit tester, and appropriate electrodes and
accessories. Additional instrumentation might include a charge plate monitor,
footwear and wrist strap testers, chart recorders and timing devices, discharge
simulators, and ESD event detectors.
Although this equipment must be accurate, it need not be as sophisticated
as laboratory instruments. The audit is intended to verify basic functions
and not as a full qualification of ESD control equipment or materials. Remember,
you want the right tool for job. Just as you would not buy a hammer if you
are were planning to saw wood, you would not purchase an electrometer to measure
static voltages on a production line. If you are making measurements according
to specific standards, be sure the instrumentation meets the specifications
of these standards.
With a hand held electrostatic field meter, you can measure
the presence of electrostatic charge in your environment allowing you to identify
problem areas and monitor your ESD control program. These instruments measure
the electrostatic field associated with a charged object. Many field meters
simply measure the gross level of the electrostatic field and should be used
as general indicators of the presence of a charge and the approximate level
of this charge. Others will provide more precise measurement for material
evaluation and comparison.
For greater precision in facility measurements or for laboratory evaluation,
a charge plate monitor can be attached to some field meters or connected
to a voltmeter in the laboratory. With these additional tools you can evaluate
the performance of flooring materials or balance ionizing equipment, for example.
Because resistance is one of the key factors in evaluating ESD control materials,
a wide range resistance meter becomes a crucial instrument. Most resistance
measurements are made at 100 volts, and some at 10 volts. The equipment you
choose should be capable of applying these voltages to the materials being
tested. In addition, the meter should be capable of measuring resistance ranges
of 105 to 1011 ohms. With the proper electrodes and
cables, you will be able to measure the resistance of flooring materials,
worksurfaces, equipment, furniture, garments, and some packaging materials.
The final instrument is a ground/circuit tester. With this device
you can measure the continuity of your ESD grounds and also check the impedance
as well as neutral to ground shorts.
Areas, Processes, and Materials to be Audited
In our last column we stated that ESD protection was required wherever
"wherever ESDS devices are handled." Obviously, our audits need
to include these same areas. Table 1 indicates some of the physical areas
that require ESD protection and auditing of the program.
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Table 1
Typical Facility Areas To Be Audited
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Receiving
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Inspection
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Stores and Warehouses
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Assembly
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Test and Inspection
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Research and Development
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Packaging
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Field Service Repair
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Offices and Laboratories
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Clean Rooms
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Similarly, we need to conduct work area and program management audits all
of the various processes, materials, and procedures that are used in our ESD
control programs. Some of these are shown in Table 2.
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Table 2
Typical Processes, Materials and Procedures
To Be Audited
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Personnel
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Moving Equipment (Carts, lift trucks)
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Wrist Straps
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Floors, Floor Mats, Floor Finishes
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Shoes, Grounders, Casters
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Clothing
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Workstations
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Worksurfaces
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Packaging and Materials
Handling
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Ionization
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Grounding
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Production Equipment
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Production Aids (Soldering irons, fixtures, etc.)
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Labeling and Identification
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Purchasing Specifications and Requisitions
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ESD Control Program Procedures and Specifications
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ESD Measurement and Test Equipment
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Personnel Training
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Engineering Specifications and Drawings
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Check Lists
Check lists can be helpful tools for conducting work place
and program audits. However, it is important that ESD control program requirements
are well documented and accessible to avoid a tendency for checklists becoming
de facto lists of requirements. Table 3 indicates the type of questions
and information that might be included in an auditing check list. Your own
check lists, of course, will be based on your specific needs and program requirements.
They should conform to your actual ESD control procedures and specifications
and they should be consistent with any requirements you may have for ISO 9000.
In addition to check lists, you will use various forms for recording the
measurements you make: resistance, voltage generation, etc. Part of your audit
will also include the daily logs used on the factory floor such as those used
for wrist strap checking.
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Table 3
Sample Audit Check List
ESD Control Program
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Function/Area Audited: Personnel
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Date:
Auditor:
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Audit Questions
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Y
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N
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Comments
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1. Where ESD protective flooring is used for personnel grounding,
are foot grounding devices or conductive footwear worn?
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2. Where conductive floors and footwear are used for personnel
grounding, do personnel check continuity to ground upon entering the
area?
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3. Are personnel wearing grounded wrist straps at the ESD protective
workstations?
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4. Are personnel checking wrist straps for continuity or using
a continuous ground monitor?
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5. Where continuous ground monitors are not used, are wrist straps
checked and logged routinely and at frequent intervals?
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6. Are wriststrap checkers and continuous ground monitors checked
and maintained periodically?
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7. Do wrist straps and foot grounders fit correctly?
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8. Are wrist straps and foot grounders working correctly?
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9. Are wrist strap cords checked, on the person, at the workstation?
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10. Are disposable foot grounders limited to one time use?
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11. Are test records for wrist straps and foot grounders kept
and maintained?
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12. When required, are ESD protective garments correctly worn?
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13. Are nonessential personal items kept out of ESD controlled
areas?
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14. Are finger cots and gloves being used on ESD sensitive hardware
made of ESD protective material, or treated to be ESD protective?
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15. Are personnel working in the ESD controlled area currently
certified or escorted?
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16. Are all personnel with access to the ESD controlled area
trained?
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17. Are ESD Control requirements imposed on visitors?
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Reporting, Corrective Action
Upon completion of the auditing process, Reports should be prepared and
distributed in a timely manner. Details of the audits need to be fully documented
for ISO-9000. As with all audits, it is essential to implement corrective
action if deficiencies are discovered. Trends need to be tracked and analyzed
to help establish corrective action, which may include retraining of personnel,
revision of requirement documents or processes, or modification of the existing
facility.
Conclusion
Auditing and training are key elements in maintaining an effective ESD
control program. They help assure that procedures are properly implemented
and can provide a management tool to gauge program effectiveness and make
continuous improvement.
For Further Reference
- "A Successful ESD Training Program," L. Snow and G. T. Dangelmayer,
EOS/ESD Symposium Proceedings, 1994, ESD Association, Rome, NY
- "A Systematic ESD Program Revisited," G. T. Dangelmayer, EOS/ESD
Symposium Proceedings, 1992, ESD Association, Rome, NY
- "Auditing-The Essential Binding Force," G.T. Dangelmayer, EOS/ESD
Symposium Tutorial, 1996
- "Developing and Maintaining an Effective ESD Training Program,"
F. Dinger, EOS/ESD Symposium Proceedings, 1988, ESD Association,
Rome, NY
- "Effectiveness of ESD Training Using Multimedia," G. Smalanskas,
J. Mason, EOS/ESD Symposium Proceedings, 1995, ESD Association, Rome,
NY
- "Employee Training for Successful ESD Control," G. T. Dangelmayer,
E. S. Jesby, EOS/ESD Symposium Proceedings, 1985, ESD Association,
Rome, NY
- "ESD Demonstrations to Increase Engineering and Manufacturing Awareness,"
G. Baumgartner, EOS/ESD Symposium Proceedings, 1996, ESD Association,
Rome, NY
- Fundamentals of ESD Evaluation and Auditing, S. Halperin, Regional
ESD Tutorial, 1998ESD Program Management: A Realistic Approach to Continuous
Improvement in Static Control, G. T. Dangelmayer, Van Nostrand Reinhold,
1999
- "Implementation of Computer-Based ESD Training: A Case Study Comparing
the Computer Approach with Traditional Classroom Techniques," J. Woodward-Jack,
H. Sommerfeld, EOS/ESD Symposium Proceedings, 1991, ESD Association,
Rome, NY
- "Implementing an ESD Program in a Multi-National Company: A Cross-Cultural
Experience," W. H. Tan, EOS/ESD Symposium Proceedings, 1994,
ESD Association, Rome, NY
- "Internal Quality Auditing and ESD Control," D. H. Smith and C.D. Rier,
EOS/ESD Symposium Proceedings, 1986, ESD Association, Rome, NY
- "Modular ESD Certification Training Program," M. Berkowitz,
B. Hamel, EOS/ESD Symposium Proceedings, 1989, ESD Association, Rome,
NY
- "The Production Operator: Weak Link or Warrior in the ESD Battle?",
G. E. Hansel, EOS/ESD Symposium Proceedings, 1983, ESD Association,
Rome, NY
- "Tracking Results of an ESD Control Program Within a Telecommunications
Service Company," R. J. Zezulka, EOS/ESD Symposium Proceedings,
1989, ESD Association, Rome, NY
- "You've Implemented An ESD Program -- What's Next?", W. Y. McFarland,
R. A. Brin, EOS/ESD Symposium Proceedings, 1993, ESD Association,
Rome, NY
- ESD ADV2.0--ESD Handbook, ESD Association, Rome, NY
- ANSI/ESD 20.20-Electrostatic Discharge Control Program, ESD Association,
Rome, NY
ESD Basics:
Part One---An Introduction to ESD
Part Two---Principles of ESD Control
Part Three---An Overview of ESD Control Procedures
and Materials
Part Four---Auditing and Training
Part Five---Device Sensitivity and Testing
Part Six---ESD Standards
January, 2000
*Article prepared by the ESD Association and originally published in
Compliance Engineering
magazine.
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