Only ESDP hand tools should be used in the EPA. Manufacturer recommendations for usage and cleaning shall be followed. Component holding trays, microscopes, and other devices or fixtures commonly found in an EPA shall be constructed of metal or permanent static dissipative plastic and shall be maintained at ground potential by placing them on a grounded tabletop while in service at the workstation.

A good practice is to have the technician always touch the metal portion of a tool when picking it up. This practice will assure that any charged metal in the tool will discharge through the technician’s wrist strap to ground.

Soldering Equipment

Soldering iron and desoldering/rework system tips shall be grounded. The resistance between the tool’s tip and its ground shall not exceed 10 ohms. All soldering iron tip grounds in an EPA shall be periodically verified. The test methodology is found in ESD DS13.1 “ESD Association Standard Test Method for Measuring Electrical Potential from Soldering/Desoldering Hand Tools”.

Desoldering Equipment

Only ESD-protective desoldering equipment shall be used when working on ESD sensitive hardware. Only antistatic solder suckers made from metal or having at least a metallized plastic barrel and dissipative tip shall be used in an EPA.

Common Ground at the Workstation

All tools, equipment, or fixtures (such as lead forming tools, test fixtures, lights and solder pots, etc.) that are too large to be placed on the protective work surface shall be connected to the common ground point.

 

Relative Humidity Control

Humidity control is important for an effective ESD program for two primary reasons;

At lower humidity levels (< 30% RH), the dissipation of commonly generated static charges does not take place, thus adding to the probability of ESD events.

Materials (such as pink poly) rely on the moisture in the air to combine with the material’s antistatic agent to form a microscopic conductive layer over the entire surface of the material. At lower humidity, (typically below 15% RH) these antistatic materials can become charged, creating an ESD hazard.

The optimum relative humidity in an EPA is 50% (plus or minus 10%).

When humidity falls below 30% RH, ESDS devices and assemblies shall be processed using special controls and procedures such as air ionization and increased awareness of the greater potential for triboelectric charging. The Facility ESD Monitor must verify the humidity prior to each shift or operation if work is not shift based unless an automatic low humidity alarm system is monitoring the work area. It is highly recommended that facility air handlers include automatic humidifiers to maintain humidity control. EPAs shall control relative humidity within a range of 30 to 70 percent relative humidity.

Air Ionizers

Air ionizers can neutralize the static charge on insulators or isolated objects by charging the molecules of the surrounding area that causes the accumulated charge to be neutralized. Air ionizers are generally used when it is not possible to properly ground everything at the workstation using previously described methods and equipment or as a back up to those methods.

As an example, most adhesive tapes are nonconductors and would require an ionizer to neutralize the charge on the tape if used in close proximity to ESDS devices. An ionizer shall be used at all, times when work is being performed in a Class 1 facility and must be available for use when needed in a Class 2 facility. Ionizers are specifically required for use in some manufacturing operations that generate static charges such as vapor degreasing, vacuum packing, spraying conformal coating, wave soldering, and the use of pressurized air guns. In addition, ionizers are a recognized static charge deterrent when humidity falls below 30 % RH. Any part sensitive to damage below 250 volts requires that an ionizer be used any time the part is removed from its ESDS packaging. Calibration of the air ionizer to verify balance and performance is required.

All permanent and semi-permanent metallic structures and test equipment utilized during handling or manufacturing of ESDS components or hardware shall be grounded using a common point ground. A major goal of this document is to ensure that all conductive materials are tied together at the same potential. An equal potential workstation is the secret to preventing damage to ESDS components.

The practice of having a separate ESD ground from the third wire (green) alternating current (AC) ground is wide spread but has the potential for damaging components because it places the operator and the work surface at a different ground potential with respect to any soldering irons and/or test equipment. The recommended practice is to use the third wire AC line ground for grounding all items at the ESDP workstation. When a separate grounding line is present or used in addition to the equipment ground, it must be bonded to the equipment ground at each ESDP station to minimize the difference in potential. ANSI EOS/ESD S6.1 “ESD Association Standard for the Protection of ESDS Items – Grounding-Recommended Practice” contains detailed hookup diagrams for ESDP workstations and support equipment.

The resistance of the conductor from the groundable point of the work surface, wrist strap, walking surface or other items to the common point ground should not be greater than 1.0 ohm. If a series resistor is used in the circuit, the total resistance shall be the value of the resistor.

The resistance of the conductor from the common point ground to the equipment ground should not be greater than 1.0 ohm.

The impedance (AC resistance) of the equipment-grounding conductor from the common point ground to the neutral bond at the main service equipment should not be greater than 1.0 ohm.

Each ESDP workstation should have a grounding block that provides sufficient wrist strap connections for all potential users. These grounding points shall not utilize portions of the protective work surface as a series element to complete the ground circuit. Receptacle grounds in an EPA shall be verified at least semiannually.

A good example of ESDP workstation setup is shown in Figure 6.5.1 Typical ESD Protective Station Grounding Systems and in ESD TR20.20-2008, Figure 13.

Stools and Chairs

Personnel performing ESDS tasks while seated should use ESDP stools and chairs. Only chairs of metallic frame construction shall be used in an EPA. Class 1 facilities shall provide ESDP chairs or stools at the workstation if seating is required. Test methods are found in ESD STM 12.1 “ESD Association Standard Test Method for the Protection of ESDS Items – Seating – Resistive Characterization”

Personnel grounding devices are the primary means of ESD control. For static charges generated during ordinary body movements, personnel-grounding devices provide a permanent path to ground. Such devices may take various forms such as:

  • Wrist Straps
  • Leg Straps
  • Heel Straps
  • Conductive Shoes

Wrist Straps

Wrist straps are considered to be the first line of defense against ESD and shall be required in the majority of ESDS work environments. Metallic contacts are preferred over conductive plastics. The wrist strap cuff shall always be in direct contact with the operator’s bare skin. It must never be worn over clothing. Bead-type chain wrist straps are prohibited.

Wrist straps shall always be worn snugly against the skin and shall not dangle freely. The electrical integrity of each wrist strap shall be checked during initial certification and verified by the operator at the beginning of every shift during which it is used. A wrist strap checker specifically designed for that purpose shall be used to verify the wrist-strap is functional. The wrist straps shall be connected to ground using one common ground point for each workstation. ESD S6.1 “Grounding Recommended Practice” outlines the recommended grounding practices.

Continuous, in-line continuity checkers are highly recommended. (Reference ESD TR20.20-2008, Section 5.3.9 – Continuous Monitors). The electrical resistance of the wrist strap measured between the opposite hand and the (ungrounded) grounding end of the wrist strap assembly shall not exceed 9M ohms above the value of the incorporated current-limiting resistance. The static dissipative work surface material shall never be used as part of the series path to ground for a wrist strap.

More information on wrist strap testing and set up is available on ESDS1.1 “ESD Standard Test Method for the Protection of ESDS Items – Wrist Straps”.

Leg Straps, Heel Straps, and Conductive Shoes

A conductive/dissipative floor and/or conductive floor mats are required when using leg straps, heel straps, and conductive shoes as acceptable alternatives to a wrist strap in those instances where the use of a wrist strap is impractical or unsafe. Examples of such instances would include working near moving conveyor belts or wave soldering machines and when working on large systems. The foot strap should have a built-in resistance of 1X106 +/- 20 percent. If the resistance does not meet this recommendation, the value should be approved by the ET&V Officer.

The ET&V Officer shall measure the conductivity of leg straps, heel straps, and conductive shoes during the initial certification. The operator shall verify this conductivity for each work shift. Test methodology is found in ESD S9.1 “ESD Association Standard Test Method for the Protection of ESDS Susceptible Items – Footwear – Resistive Characterization”.

 

Conductive floors or grounded conductive floor mats are mandatory in any EPA where personnel handling ESDS items are not wearing wrist straps. Under these circumstances, personnel shall use leg straps, heel straps, or conductive shoes.

ESDP flooring or floor mats shall be used in all Class 1 facilities.

The proper cleaning and maintenance of a conductive floor is of extreme importance since the use of normal floor wax on conductive floors or floor mats can defeat their effectiveness. Personnel cleaning these items shall use the manufacturer approved cleaning agents and cleaning recommendations as minimum requirements. With guidance from the ET&V Officer, the Facility ESD Monitor will determine the cleaning regimen for the flooring and mats if the manufacturer’s recommendations are not acceptable.

Conductive/dissipative floors or grounded conductive/dissipative floor mats shall have a maximum resistance to ground of 1×109 ohms and a minimum resistance of 1×105 ohms. The test methodology for flooring is found in ESD S7.1 “ESD Association Standard Test Method for the Protection of ESDS Items – Resistive Characteristics of Materials – Floor Materials”.

Standard carpeting shall not be used in an EPA. Even the use of ESDP carpet woven with conductive fibers, which have previously been approved for use at JSC, can still be very problematic. If the conductive fibers are not dense enough, the resistance to ground will increase as the carpet wears. The selection of carpet in an EPA environment shall require pre-installation approval of the ET&V Officer.

The ESDP work surface (Reference ESD TR20.20-2008, section 5.3.1 – Work surfaces) will provide a safe path to ground for static charges within the operator’s general working area. Either the ESDP work surface may be fabricated as a part of the workbench or it may be a separate addon item. In either case, the ESDP work surface shall be grounded and static dissipative with a resistance to ground measurement between 1×106 to 1×109 ohms. Applications where hard grounding of the LRU is required are excluded. ESD S4.1 “ESD Association Standard Method for the Protection of ESDS Items – Workstation – Resistive Characterization” describes the test methods for work surfaces. Grounding of the work surface may be accomplished with the use of a current limiting resistor that is generally a ¼ watt, 250V part. The maximum voltage rating of the resistor defines the maximum working voltage of the surface. The use of a series resistor is recommended for personnel safety if the currents from accessible voltages at the workstation could exceed 5mA through the static-dissipative protective work surface. For personnel safety, the use of a ground fault circuit interrupter (GFCI) is recommended in situations where personnel may come in contact with hazardous current levels.

The ET&V Officer shall check the work surface ground continuity during initial certification. Thereafter this check can be done by lab personnel on a weekly basis. It is strongly recommended that electronic monitors be used to monitor continuously the integrity of the work surface ground.

The manufacturer’s recommended chemicals and methods that will not damage the work surface shall be used to clean the work surface as required.

Exposed metalwork surfaces are not acceptable for ESD workstations. If a special situation requires a conductive work surfaces, it must be hard grounded. If a painted metal bench is used, the metal must be covered with a static dissipative material. See Figure 6.5.1 and Figure 6.5.2 for examples of how a workstation should be connected to meet ESD requirements.

Typical ESD Protective Station Grounding Systems

Figure 6.5.1 Typical ESD Protective Station Grounding Systems

Typical Barrier Strip Common Ground Point

Figure 6.5.2 Typical Barrier Strip Common Ground Point

 Dispersion Leakage Elimination Electrostatic Method

For synthetic fiber fabrics, the conductivity of the fabrics can be increased by reducing the resistance. The main method of reducing resistance is to use surfactants to hydrophilicize the fibers or fabrics, so as to improve the hygroscopicity of the fibers, thereby reducing the resistance of textiles, speeding up the charge dissipation, dispersing the charge and eliminating static electricity through propagating, leaking. The antistatic effect of this method is difficult to preserve for a long time, the washing resistance is poor, and the antistatic performance is not shown under low humidity conditions. In addition, in order to reduce the production of electrostatic charge, antistatic oils coated on the interface of textile materials make the friction and contact between materials insufficient and direct, thus reducing the charge transfer. 。 Another mechanism is that the hydrophobic end of surfactant molecule is adsorbed on the surface of the fiber, and hydrophilic groups point to the space, forming a polar interface, adsorbing water molecules in the air, reducing the surface specific resistance of the fiber or fabric, and accelerating the charge dissipation. This is the main way most antistatic agents work. Another way that antistatic agent works is ionization. Ionized antistatic agent itself has good conductivity. Under the action of surface water molecule, this kind of oil agent molecule ionizes, which significantly improves the conductivity of the fiber surface. At the same time, it can eliminate charges by neutralizing the surface charge.

 Dispersion Leakage Elimination Electrostatic Method

Chemical Modification Methods

Antistatic fibers were prepared by blending, copolymerization, grafting modification of fibre-forming polymers, introducing hydrophilic polar groups, or adding antistatic agents inside the fibers. Its common characteristic is to improve the hygroscopicity of fibers and accelerate the charge dissipation. Textiles made from antistatic fibers or blended with high proportion of synthetic fibers can eliminate electrostatic problems in processing and use, but the high humidity environment is still a necessary condition for charge dissipation.

Chemical Modification Methods

Corona discharge method for eliminating static electricity

Fabrics are made of uniformly mixed textile fibers and conductive fibers. Conductive homogeneous conductive fibers such as metal fibers, carbon fibers and conductive polymers or conductive materials such as carbon black coated on the outer layer of synthetic fibers are used to coat conductive fibers, and conductive materials such as carbon black or metal compound polymers are used to prepare conductive composite conductive fibers by composite spinning. The application of conductive fibers makes textiles have remarkable antistatic effect, durability and not affected by environmental humidity, and can be applied to special functional textiles such as antistatic work clothes. Using different electrostatic sequences, different fibers are blended or interwoven to reduce electrostatic.

corona-discharge-method-for-eliminating-static-electricity

The application and development of conductive fibers in the above three methods are the direction of antistatic product development. At present, more and more attention has been paid to them. However, there are many problems that need to be further discussed in the application. For example, the anti-static mechanism of conductive fiber inlay and the evaluation method of anti-static property of fabric containing conductive fiber need to be further studied and discussed.

Cleanroom testing is a very necessary process before the cleanroom is used by the owner after construction. Whether the cleanroom testing meets the standards will directly lead to whether the cleanroom meets the production requirements.

According to the standard of IES-RP-CC006.2 cleanroom test, the working state of cleanroom may fall into three states: empty, static and dynamic. The testing mode depends on the type of cleanroom design and the working state of cleanroom.

Working state of cleanroom

In the construction contract of cleanroom, only the most basic air test is usually specified, while the static and dynamic test is often omitted because of the tight schedule. However, we still recommend that both contractors and owners test the cleanroom under static and dynamic conditions. This will ensure that the construction of the cleanroom meets the design requirements. The comparison of test results under two different conditions, static and dynamic, will provide a very effective help for the analysis of the problems existing in the cleanroom.

For example, under static conditions, the cleanliness reaches the standard, while under dynamic conditions, it doesn’t meet the standard. This may be due to poor cleanroom management: non-standard cleaning when installing machines, inappropriate cleaning procedures, inadequate discipline management, incorrect machine placement (blocking the vent or blocking the air supply of filters), etc.

Therefore, we recommend that the cleanroom be tested in both static and dynamic conditions.

Cleanroom Performance Testing and Reference to Relevant Certification Standard

Cleanroom testing standards and practices

All cleanroom tests are basically based on internationally recognized standards (e.g. ISO14644-1; IEST-RP-CC006.2; NEBB manual and terminated FS-209E). These standards and practices provide the most basic guidance for cleanroom testing and certification. In fact, owners and builders of cleanrooms have different agreements on technical indicators, testing methods and acceptance standards of cleanrooms due to product and process requirements.

Therefore, most acceptance criteria are agreed upon by the owner and builder of the cleanroom through consultation and referring to the recommendations of the professional cleanroom testing and certification company. Since independent third-party testing and certification companies can usually propose suitable solutions for cleanroom testing, we recommend that owners and builders invite testing and certification companies to participate in the discussion of cleanroom technical parameters, testing methods and acceptance criteria. In case of disagreement on relevant parameters or standards, the testing and certification company will act as a mediator between the owner and the builder with their own expertise.

Selection of test items

The recommended cleanroom test items include the uniformity of the air velocity of the filter, leak detection of the filter installation, differential pressure, airflow parallelism, cleanliness, noise, illumination, humidity/temperature and so on. These are the basic test items, which include the main and auxiliary test items. These items should be consistent with the original design criteria and parameters of the clea room, and the test certification should be completed before the cleanroom is transferred to the owner.

Four main items (filter wind speed and uniformity, filter installation leak detection, differential pressure and cleanliness) are the most important and basic in all test items. It must be completed before the equipment enters the cleanroom. Other auxiliary test items such as airflow parallelism (only applicable to one-way flow clean room), temperature, humidity, illumination, noise also need to be completed, because they are related to the movement and environmental parameters of air in clean room. We believe that these auxiliary tests need to be done at least under dynamic conditions.

The performance test of cleanroom is a means to check whether the cleanroom project meets the standards, which will directly affect whether the cleanroom meets the production requirements. Therefore, enterprises should pay attention to the performance test of clean rooms.

1.This presentation addresses the walking test as described in ANSI/ESD STM 97.2. The use of this test method is required by any ESD control program claiming compliance to ANSI/ESD S20.20 when an ESD floor or ESD floor mat is used as primary ground for personnel. In these situations, the walking test must be performed during the qualification of the footwear flooring system. Testing must be performed for every footwear type used in 2020 compliant ESD program.

A test report, containing the findings, must be available as evidence that qualification testing was performed.

Footwear/Flooring System Walking Test Demonstration

2.For qualification testing, a sample of the intended floor is assembled according to the flooring manufacturer’s instructions and the sample is connected to ground. The size of the flooring sample shall be at least 91 cm x 91 cm so that an effective walking pattern can be established.

The test subject is connected to a charged plate monitor and a device that can record the voltage seen by charged plate monitor.

The ESD footwear that will be used with the static control flooring must be used for this test. ESD footwear can be ESD shoes, booties, heelstraps or sole grounders. Whichever type footwear is selected the footwear must be worn on both feet.

Footwear/Flooring System Walking Test Demonstration

3.ANSI/ESD STM97.2 requires that the test subject walk in a set pattern as shown in this slide. The test subject starts with their feet at positions 5 and 6. Once started the test subject moves without stopping until they return to the starting position. At this point the test subject pauses for at least two seconds before repeating the walking sequence. The walking pattern needs to be repeated a minimum of 10 times according to the test method or until the voltage stabilizes.

It is necessary to have equipment to measure and record the voltage on the person performing the test.

Footwear/Flooring System Walking Test Demonstration

4.The video on this slide demonstrates the walking pattern. As you can see the test subject pauses at the end fo the test cycle as required by the test method.

5.The slide shows an example of a walking test. The peak voltages for this footwear flooring combination are less than 100 volts which meets the requirements of ANSI/ESD S20.20.

Footwear/Flooring System Walking Test Demonstration

6.Please send any question concerning this presentation to [email protected]

 

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The electronics industry is continually shifting. Device density and technology is more complex. Electronics manufacturing is more heavily reliant on out-sourcing. The ESD industry seems to have jumped into this swirling eddy headfirst. ESD control programs have mushroomed. Black has been replaced by green, blue and gold. Shielding bags dominate the warehouse. Ionizers exist along side wrist straps and ground cords. An early history of “smoke and mirrors,” magic and lofty claims of performance is rapidly and safely being relegated to the past.

Today, more than ever, meeting the complex challenge of reducing ESD losses requires more than reliance on faith alone. Users require a way to legitimately evaluate and compare competing brands and types of products. They need objective confirmation that their ESD control program provides effective solutions to their unique ESD problems. Contract manufacturers and OEM’s require mutually agreed-upon ESD control programs that reduce duplication of process controls.

That’s where standards come into play. They provide guidance in developing programs that effectively address ESD process control. They help define the sensitivity of the products manufactured and used. They help define the performance requirements for various ESD control materials, instruments, and tools. Standards are playing an ever-increasing role in reducing marketplace confusion in the manufacture, evaluation, and selection of ESD control products and programs.

The Who and Why of Standards

Who uses ESD standards? Manufacturers and users of ESD sensitive devices and products, manufacturers and distributors of ESD control products, certification registrars, and third party testers of ESD control products.

Why use ESD standards? They help assure consistency of ESD sensitive products and consistency of ESD control products and services. They provide a means of objective evaluation and comparison among competitive ESD control products. They help reduce conflicts between users and suppliers of ESD control products. They help in developing, implementing, auditing, and certifying ESD control programs. And, they help reduce confusion in the marketplace.

In the United States, the use of standards is voluntary, although their use can be written into contracts or purchasing agreements between buyer and seller. In most of the rest of the world, the use of standards, where they exist, is compulsory.

Key Standards and Organizations

Just 20 years ago, there were relatively few reliable ESD standards and few ESD standards development organizations. Today’s ESD standards landscape is not only witnessing an increase in the number of standards, but also increasing cooperation among the organizations that develop them.

Today’s standards fall into three main groups. First, there are those that provide ESD program guidance or requirements. These include documents such as ANSI ESD S20.20-2007–Standard for the Development of an ESD Control Program, ANSI/ESD S8.1-Symbols-ESD Awareness , or ESD TR20.20-ESD Handbook.

A second group covers requirements for specific products or procedures such as packaging requirements and grounding. Typical standards in this group are ANSI/ESD S6.1-Grounding and ANSI/ESD S541 –Packaging Materials for ESD Sensitive Items.

A third group of documents covers the standardized test methods used to evaluate products and materials. Historically, the electronics industry relied heavily on test methods established for other industries or even for other materials (e. g., ASTM-257-DC Resistance or Conductance of Insulating Materials). Today, however, specific test method standards focus on ESD in the electronics environment, largely as a result of the ESD Association’s activity. These include standards such as ANSI/ESDA-JEDEC JS-001-2010-Device Testing, Human Body Model and ANSI/ESD STM7.1: Floor Materials — Resistive Characterization of Materials to cite just a few.

Who Develops Standards?

Standards development and usage is a cooperative effort among all organizations and individuals affected by standards. There are several key ESD standards development organizations.

Military Standards

Traditionally, the U.S. military spearheaded the development of specific standards and specifications with regard to ESD control in the U.S. Today, however, U.S. military agencies are taking a less proactive approach, relying on commercially developed standards rather than developing standards themselves. For example, the ESD Association completed the assignment from the Department of Defense to convert MIL-STD-1686 into a commercial standard called ANSI/ESD S20.20.

ESD Association

The ESD Association has been a focal point for the development of ESD standards in recent years. An ANSI-accredited standards development organization, the Association is charged with the development of ESD standards and test methods. The Association also represents the US on the International Electrotechnical Commission (IEC) Technical Committee 101-Electrostatics.

The ESD Association has published 36 standards documents and 23 Technical Reports. These voluntary standards cover the areas of material requirements, electrostatic sensitivity, and test methodology for evaluating ESD control materials and products. In addition to standards documents, the Association also has published a number of informational advisories. Advisory documents may be changed to other document types in the future.

ESD Association Standards Classifications and Definitions

There are four types of ESD Association standards documents with specific clarity of definition. The four document categories are consistent with other standards development organizations. These four categories are defined below.

  • Standard: A precise statement of a set of requirements to be satisfied by a material, product, system or process that also specifies the procedures for determining whether each of the requirements is satisfied.
  • Standard Test Method: A definitive procedure for the identification, measurement and evaluation of one or more qualities, characteristics or properties of a material, product, system or process that yields a reproducible test result.
  • Standard Practice: A procedure for performing one or more operations or functions that may or may not yield a test result. Note: If a test result is obtained, it may not be reproducible between labs.
  • Technical Report: A collection of technical data or test results published as an informational reference on a specific material, product, system, or process.

As new documents are approved and issued, they will be designated into one of these four new categories. Existing documents have been reviewed and have been reclassified as appropriate. Several Advisory Documents still exist and may be migrated to either Technical Reports or Standard Practices in the future.

International Standards

The international community, led by the European-based International Electrotechnical Commission (IEC), has also climbed on board the standards express. IEC Technical Committee 101 has released a series of documents under the heading IEC 61340. The documents contain general information regarding electrostatics, standard test methods, general practices and an ESD Control Program Development Standard that is technically equivalent to ANSI/ESD S20.20.  A Facility Certification Program is also available.  Global companies can seek to become certified to both ANSI/ESD S20.20 and to IEC61340-5-1 if they so choose. Japan also has released its proposed version of a national electrostatic Standard, which also shares many aspects of the European and U.S. documents.

Organizational Cooperation

Perhaps one of the more intriguing changes in ESD standards has been the organizational cooperation developing between various groups.  One cooperative effort was between the ESD Association and the U.S. Department of Defense, which resulted in the Association preparing ANSI/ESD S20.20 as a successor to MIL-STD-1686.  A second cooperative effort occurred between the ESD Association and JEDEC, which started with an MOU and resulted in the development of 2 documents: a joint HBM document was published in 2010; a joint CDM document will be published in 2011.

Internationally, European standards development organizations and the ESD Association have developed working relationships that result in an expanded review of proposed documents, greater input, and closer harmonization of standards that impact the international electronics community.

For users of ESD standards, this increased cooperation will have a significant impact. First, we should see standards that are technically improved due to broader input. Second, we should see fewer conflicts between different standards. Finally, we should see less duplication of effort.

Summary

For the electronics community, the rapid propagation of ESD standards and continuing change in the standards environment mean greater availability of the technical references that will help improve ESD control programs. There will be recommendations to help set up effective programs. There will be test methods and specifications to help users of ESD control materials evaluate and select products that are applicable to their specific needs. And there will be guidelines for vendors of ESD products and materials to help them develop products that meet the real needs of their customers.

Standards will continue to fuel change in the international ESD community.

Sources of Standards

ESD Association, 7900 Turin Road, Building 3, Rome, NY 13440. Phone: 315-339-6937. Fax: 315-339-6793. Web Site: http://www.esda.org

IHS Global Engineering Documents, 15 Inverness Way East, Englewood, CO 80112. Phone: 800-854-7179. Fax: 303-397-2740. Web Site: http://global.ihs.com

International Electrotechnical Commission, 3, rue de Varembe, Case postale 131, 1211 Geneva 20, Switzerland. Fax: 41-22-919-0300. Web Site: http://www.iec.ch/

Military Standards, Naval Publications and Forms Center, 5801 Tabor Avenue, Philadelphia, PA 19120

JEDEC Solid State Technology Association, 3103 North 10th Street, Suite 240-S
Arlington, VA  22201-2107, http://www.jedec.org

Principle ESD Standards

U.S. Military/Department of Defense

MIL-STD-1686C: Electrostatic Discharge Control Program for Protection of Electrical and Electronic Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices) This military standard establishes requirements for ESD Control Programs. It applies to U.S. military agencies, contractors, subcontractors, suppliers and vendors. It requires the establishment, implementation and documentation of ESD control programs for static sensitive devices, but does NOT mandate or preclude the use of any specific ESD control materials, products, or procedures. It is being updated and converted to a commercial standard by the ESD Association. Although DOD has accepted the new ANSI/ESD S20.20 document as a successor, it has not yet taken action to cancel STD-1686

MIL-HBDK-263B: Electrostatic Discharge Control Handbook for Protection of Electrical and Electronic Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices)
This document provides guidance, but NOT mandatory requirements, for the establishment and implementation of an electrostatic discharge control program in accordance with the requirements of MIL-STD-1686.

MIL-PRF 87893—Workstation, Electrostatic Discharge (ESD) Control
This document defines the requirements for ESD protective workstations.

MIL-PRF-81705—Barrier Materials, Flexible, Electrostatic Protective, Heat Sealable
This documents defines requirements for ESD protective flexible packaging materials.

MIL-STD-129—Marking for Shipment and Storage
Covers procedures for marketing and labeling ESD sensitive items.

ESD Association

Standards Documents

ANSI/ESD S1.1: Evaluation, Acceptance, and Functional Testing of Wrist Straps
A successor to EOS/ESD S1.0, this document establishes test methods for evaluating the electrical and mechanical characteristics of wrist straps. It includes improved test methods and performance limits for evaluation, acceptance, and functional testing of wrist straps.

ANSI/ESD STM2.1: Resistance Test Method for Electrostatic Discharge Protective Garments
This Standard Test Method provides test methods for measuring the electrical resistance of garments used to control electrostatic discharge. It covers procedures for measuring sleeve-to-sleeve and point-to-point resistance.

ANSI/ESD STM3.1-: Ionization 
Test methods and procedures for evaluating and selecting air ionization equipment and systems are covered in this standard. The document establishes measurement techniques to determine ion balance and charge neutralization time for ionizers.

ANSI/ESD SP3.3: Periodic Verification of Air Ionizers.
This Standard Practice provides test methods and procedures for periodic verification of the performance of air ionization equipment and systems (ionizers).

ANSI/ESD S4.1: Worksurfaces – Resistance Measurements
This Standard establishes test methods for measuring the electrical resistance of worksurface materials used at workstations for protection of ESD susceptible items. It includes methods for evaluating and selecting materials, and testing new worksurface installations and previously installed worksurfaces.

ANSI/ESD STM4.2: Worksurfaces – Charge Dissipation Characteristics
This Standard Test Method provides a test method to measure the electrostatic charge dissipation characteristics of worksurfaces used for ESD control. The procedure is designed for use in a laboratory environment for qualification, evaluation or acceptance of worksurfaces.

ESDA-JEDEC  JS-001: Electrostatic Discharge Sensitivity Testing — Human Body Model
This Standard Test Method updates and revises an existing Standard. It establishes a procedure for testing, evaluating and classifying the ESD sensitivity of components to the defined Human Body Model (HBM).

ANSI/ESD STM5.2): Electrostatic Discharge Sensitivity Testing — Machine Model
This Standard establishes a test procedure for evaluating the ESD sensitivity of components to a defined Machine Model (MM).  The component damage caused by the Machine Model is often similar to that caused by the Human Body Model, but it occurs at a significantly lower voltage.

ANSI/ESD STM5.3.1: Electrostatic Discharge Sensitivity Testing – Charged Device Model — Non-Socketed Mode
This Standard Test Method establishes a test method for evaluating the ESD sensitivity of active and passive components to a defined Charged Device Model (CDM).

ANSI/ESD SP5.3.2: Electrostatic Discharge Sensitivity Testing. – Socketed Device Method (SDM) – component Level.     
This standard practice provides a test method generating a Socketed Device Model (SDM) test on a component integrated circuit (IC) device.

ANSI/ESD SP5.4:  Latchup Sensitivity Testing of CMOS/BiCMOS Integrated Circuits. – Transient Latchup Testing – Component Level Suppl Transient simulation.
This standard practice method was developed to instruct the reader on the methods and materials needed to perform Transient latchup testing.

ANSI/ESD STM5.5.1:Electrostatic Discharge Sensitivity Testing – Transmission Line Pulse (TLP) – Component Level.
This document pertains to Transmission Line Pulse (TLP) testing techniques of semiconductor components. The purpose of this document is to establish a methodology for both testing and reporting information associated with TLP testing.

ANSI/ESD SP5.5.2Electrostatic Discharge Sensitivity Testing – Very Fast Transmission Line Pulse (VF-TLP) – Component Level 
This document pertains to Very Fast Transmission Line Pulse (VF-TLP) testing techniques of semiconductor components.  It establishes guidelines and standard practices presently used by development, research, and reliability engineers in both universities and industry for VF-TLP testing.  This document explains a methodology for both testing and reporting information associated with VF-TLP testing.

ANSI/ESD SP5.6:   Electrostatic Discharge Sensitivity Testing – Human Metal Model (HMM) – Component Level
Establishes the procedure for testing, evaluating, and classifying the ESD sensitivity of components to the defined HMM.

ANSI/ESD S6.1: Grounding  
This Standard recommends the parameters, procedures, and types of materials needed to establish an ESD grounding system for the protection of electronic hardware from ESD damage. This system is used for personnel grounding devices, worksurfaces, chairs, carts, floors, and other related equipment.

ANSI ESD S7.1: Floor Materials — Resistive Characterization of Materials 
Measurement of the electrical resistance of various floor materials such as floor coverings, mats, and floor finishes is covered in this document. It provides test methods for qualifying floor materials before installation or application and for evaluating and monitoring materials after installation or application.

ANSI ESD S8.1: ESD Awareness Symbols
Three types of ESD awareness symbols are established by this document. The first one is to be used on a device or assembly to indicate that it is susceptible to electrostatic charge. The second is to be used on items and materials intended to provide electrostatic protection. The third symbol indicates the common point ground

ANSI/ESD S9.1: Resistive Characterization of Footwear
This Standard defines a test method for measuring the electrical resistance of shoes used for ESD control in the electronics environment.

ANSI/ESD SP10.1: Automated Handling Equipment
This Standard Practice provides procedures for evaluating the electrostatic environment associated with automated handling equipment.

ANSI ESD STM11.11: Surface Resistance Measurement of Static Dissipative Planar Materials 
This Standard Test Method defines a direct current test method for measuring electrical resistance. The Standard is designed specifically for static dissipative planar materials used in packaging of ESD sensitive devices and components.

ANSI/ESD STM11.12: Volume Resistance Measurement of Static Dissipative Planar Materials
This Standard Test Method provides test methods for measuring the volume resistance of static dissipative planar materials used in the packaging of ESD sensitive devices and components.

ANSI/ESD STM11.13: Two-Point Resistance Measurement
This Standard Test Method provides a test method to measure the resistance between two points on an items surface.

ANSI ESD STM11.31: Evaluating the Performance of Electrostatic Discharge Shielding Bags 
This Standard provides a method for testing and determining the shielding capabilities of electrostatic shielding bags.

ANSI/ESD STM12.1: Seating-Resistive Characterization
This Standard provides test methods for measuring the electrical resistance of seating used to control ESD. The test methods can be used for qualification testing as well as for evaluating and monitoring seating after installation. It covers all types of seating, including chairs and stools.

ANSI/ESD STM13.1: Electrical Soldering/Desoldering Hand Tools
This Standard Test Method provides electric soldering/desoldering hand tool test methods for measuring the electrical leakage and tip to ground reference point resistance and provides parameters for EOS safe soldering operation.

ANSI/ESD SP15.1: Standard Practice for In-Use Testing of Gloves and Finger Cots
This document provides test procedures for measuring the intrinsic electrical resistance of gloves and finger cots as well as their electrical resistance together with personnel as a system.

ANSI ESD S20.20: Standard for the Development of an ESD Control Program
This Standard provides administrative, technical requirements and guidance for establishing, implementing and maintaining an ESD Control Program.

ANSI/ESD STM97.1: Floor Materials and Footwear – Resistance in Combination with a Person.
This Standard Test Method provides for measuring the electrical resistance of floor materials, footwear and personnel together, as a system.

ANSI/ESD STM97.2- Floor Materials and Footwear Voltage Measurement in Combination with a Person
This Standard Test Method provides for measuring the electrostatic voltage on a person in combination with floor materials and footwear, as a system.

Advisory Documents

Advisory Documents and Technical Reports are not Standards, but provide general information for the industry or additional information to aid in better understanding of Association Standards.

  • ESD ADV1.0: Glossary of Terms
    Definitions and explanations of various terms used in Association Standards and documents are covered in this Advisory. It also includes other terms commonly used in the ESD industry.
  • ESD ADV3.2: Selection and Acceptance of Air Ionizers
    This Advisory document provides end users with guidelines for creating a performance specification for selecting air ionization systems. It reviews four types of air ionizers and discusses applications, test method references, and general design, performance and safety requirements.
  • ESD ADV11.2: Triboelectric Charge Accumulation Testing
    The complex phenomenon of triboelectric charging is discussed in this Advisory. It covers the theory and effects of tribocharging. It reviews procedures and problems associated with various test methods that are often used to evaluate triboelectrification characteristics. The test methods reviewed indicate gross levels of charge and polarity, but are not necessarily repeatable in real world situations.
  • ESD TR53.1: ESD Protective Workstations
    This Advisory document defines the minimum requirements for a basic ESD protective workstation used in ESD sensitive areas. It provides a test method for evaluating and monitoring workstations. It defines workstations as having the following components: support structure, static dissipative worksurface, a means of grounding personnel, and any attached shelving or drawers.
  • ESD TR 20.20: ESD Handbook
    New handbook provides detailed guidance for implementing an ESD control program in accordance with ANSI/ESD S20.20.