ESD Control Program Periodic Verification
Fred Tenzer and Gene Felder, Desco Industries, Inc.
Want to accomplish something important? A familiar formula is write a plan, select the speciﬁcations, and then periodically test to verify that the plan is being implemented according to the test results. This is basically the requirements of an ESD control program, per the ESD Association standard, ANSI/ESD S20.20. This important standard, entitled Development of an Electrostatic Discharge Control Program, covers the requirements necessary to design, establish, implement, and maintain an ESD control program to protect electrical or electronic parts, assemblies and equipment susceptible to ESD damage.
S20.20 is a process document, and provides ESD control plan guidance; one of its requirements is having a “compliance veriﬁcation plan” as a component of the ESD control plan. Per S20.20, paragraph 6.1.3., Compliance Veriﬁcation Plan:
To view more information on ESD Control Program Periodic Veriﬁcation CLICK HERE
Application Photo of Surface Resistance Test Kit
A significant increase in the discipline of implementing the fundamentals of ESD control noted in ANSI/ESD S20.20 Foreword, calls for:
- Ground all conductors in the EPA including people
- Remove all insulators from the EPA or use ionizers for process necessary insulators
- Package ESD sensitive items going outside the EPA in packaging that provides electrostatic discharge shielding
We encourage developing a hatred for insulators. The alternatives are:
Remove the insulative item from the EPA
- Substitute the item with an ESD protective version (such as tape, document holders, material handling containers, plastic bottles, etc.)
- Periodically treat insulative surface with a topical antistat
- Neutralize electrostatic charges using ionization
Other ESD Control Items
Other EPA ESD control items to add to the ESD control program might include shelving, mobile equipment (carts), gloves, and/or seating.
Improve Compliance Verification Plan
- Consider greater frequency of internal audits per ESD TR53
- Use of computer data collection system for wrist straps and footwear testing, continuous monitors, and ionizers
- Use of ground continuous monitors for worksurfaces and other ESD elements
- Test ionizers more frequently, consider self monitoring ionizers, consider computer based data collection
- Increased testing using static field meter to verify that automated processes (like auto insertion, tape and reel, etc) are not generating charges above acceptable limits.
Application Photo of Volt Meter and Software in Factory STM97.2 Testing Voltage Charge on Person (Photograph courtesy of TREK, INC.)
- ESD awareness training for all in the EPA or who may come into the EPA including suppliers
- Testing to verify comprehension and training adequacy
- Training on the proper use of test equipment
- Training on proper compliance verification test procedures
Application Photo CD-ROM ESD Training
Just to maintain a company’s current level of quality and reliability may require a substantial improvement in a company’s ESD control program. Now is the time for improvement as ESD sensitivity withstand voltages continue to get lower and companies may soon be handling class 0A HBM items. To combat HBM failures improved personnel grounding is required. For example, heel grounders should be replaced with full coverage foot grounders. However, most failures are CDM. To combat CDM failures, ionization should be added or improved, and conductive surfaces should be covered with dissipative material. In general, disciple should be enhanced implementing ESD control fundamentals, compliance verification testing should be increased, and training should be improved.
From published article “Now is the Time for ESD Control Programs to be Improved” by Fred Tenzer and Gene Felder. See full article at InCompliance Magazine- September 2012