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Listed below are compiled packaging FAQs for the 'Electrostatic Discharge Sensitive (ESDS)' topic. Our ESDS web page identifies why items are ESD sensitive, the type of preservation method required to protect the item, acceptable packaging materials, and workstation requirements. If your question is not listed, please use either our feedback form to add a Packaging FAQ to this listing or contact us directly by E-mailing your Questions or Comments to: DSCC.packaging@dla.mil
NAVIGATIONAL BAR: | OVERVIEW | PRESERVATION METHOD | ACCEPTABLE MATERIALS | HANDLING PROCEDURES | ESD WORKSTATION | ESD FIELD SERVICE KIT| DOCUMENTS | MARKINGS | TRAINING |
- What is Electrostatic Discharge?
- A transfer of electrostatic charges between bodies at different electrostatic potentials caused by direct contact or induced by an electrostatic field.
- The following are some examples of electrostatic charges:
1. Walking across a nylon carpet on a dry day generates a static electrical charge of 35,000 volts.
2. Opening a plastic bag generates a charge of 20,000 volts.
- Fire control and navigation systems on equipment such as the M-1 tank and F-18 aircraft are controlled by electronic microchips so sensitive that a static charge of 30 - 50 volts of static electricity may cause the equipment to malfunction during deployment or combat missions. Many of these defects are traced to careless handling and packaging of items sensitive to electrostatic discharge.
- For more information on Electrostatic Discharge, we encourage you to visit the Electrostatic Discharge Association's
 web site.
- What is Electromagnetic Interference (EMI)?
EMI sources include sparks, lightening, radar, radio and TV transmission. EMI may cause induce damaging voltage surges to electronic components.
- Why are items sensitive to electrostatic discharges?
While microchips have grown smaller with greater functional capabilities, the components have become increasingly more complex requiring minute amounts of electrical current in terms of microvolts (one-millionth of a volt). These items are sensitive/susceptible to damage caused by static electricity and or electromagnetic forces. Thus, requiring electrostatic/electromagnetic protective packaging materials, special marking, special workstations, clothing, equipment, and handling procedures.
- Are there different types of ESD damage?
Yes. Electrostatic discharge damage can take the form of upset failures or catastrophic failures.
- UPSET FAILURES result in gate leakage.
- CATASTROPHIC FAILURES occur in two forms: Direct and Latent failures.
UPSET FAILURES occur when an electrostatic discharge (ESD) has caused a current flow that is not significant to cause total failure. However, in use it may intermittently result in gate leakage causing loss of software or incorrect storage of information. Upset or latent failures may pass your company's quality control testing program.
DIRECT CATASTROPHIC FAILURES occur when a component is damaged to the the point where it is dead now and will never again function. This is the easiest type of ESD damage to find, since it usually can be detected during testing.
LATENT FAILURES occur when ESD weakens or wounds the component to the point where it will still function properly during testing. However, over time the wounded component will cause poor system performance and eventually complete system failure. Because latent failures occur after final inspection or in the hands of our customers, the cost for repair is very high. Not only is this type of damage hard to find, it severely affects the performance of weapons systems and adversely affects the reputation of the supplying contractor's product. Therefore, it is imperative that ESD packaging and handling procedures be followed completely.
REMEMBER: ESD is an invisible enemy and prevention is the only way you can combat those forces. Our Military Forces are counting on your company to properly handle and package items to ensure they have reliable systems. Let's work together to provide our Military personnel the excellent support they deserve.
- Why do I have to apply MIL-PRF-81705 barrier materials?
ESD protective materials limit static electricity generation by rapidly dissipating electrostatic charges over
its surface or volume or provides shielding against electromagnetic interference forces. These barrier materials are used to fabricate enclosures for electrostatic
sensitive equipment and components. They are especially formulated to prevent the build-up or retention of electrostatic potential, the objective being to maximize
explosive safety, to protect miniature electronic parts, and to preclude ignition of stray flammable materials. Guidance in the application of these materials may be
found in DOD-STD-1686 and DOD-HDBK-263.
- Type I barrier material - is intended for use for the watervaporproof electrostatic and electromagnetic protection of microcircuits, certain semi-conductor devices (such as microwave diodes and field effect transistors, sensitive resistors and other miniature electronic parts requiring this protection). It is also used where contact with oil or grease is contemplated.
- Type II barrier material - is intended for use for the waterproof electrostatic, protective transparent barrier is required and contact with oil or grease is not contemplated.
- How can I identify if an item is electrostatic discharge (ESD) sensitive?
Drawings, specifications, technical sheets, and packaging/marking requirements usually identify items which are ESD sensitive.
- What is a 'Ground'?
A mass such as earth, a vehicle hull, or building frame capable of accepting a large electrical charge.
- Where can I find the requirements of a 'GX' preservation method code?
The 'GX' preservation method code can be found in MIL-STD-2073, within Table J.Ia (Specialized Preservation Codes).
- What are the requirements of a 'GX' preservation method code?
MIL-STD-2073, Table J.Ia requirements state to, 'Preserve by Method 41 as follows: Items subjected to damage by
electromagnetic and electrostatic field forces shall be initially wrapped in material conforming to MIL-PRF-81705, Type II or Type III, or cushioned in material conforming to
PPP-C-1842, Type III, Style A or B, or PPP-C-795, Class 2, or PPP-C-1752, Type VII, Class 1, Grade B, or PPP-C-1797, Type II, to prevent bag puncture, and unit packed in a
heat-sealed bag conforming to MIL-DTL-117, Type I, Class F, Style 1. Reclosable cushioned pouches conforming to MIL-DTL-81997, Type I or Type II, may be used in lieu of initial
wrap or cushioning. Lead or terminals configurations for all items shall be maintained as manufactured without causing loads or stresses capable of causing damage to the item.
Materials used to maintain item position and lead or terminal configuration shall permit item removal without damage to the item. Electrostatic discharge (ESD) sensitive caution
labels shall be applied in accordance with MIL-STD-129.'
- When I have a preservation method code 'GX' listed in a solicitation or contract, what are the acceptable materials I can used?
- Barrier Bag Materials:
- heat-sealed bag conforming to MIL-DTL-117, Type I, Class F, Style 1
- Acceptable substitutes: Reclosable cushioned pouches conforming to MIL-DTL-81997, Type I, or
- MIL-DTL-81997, Type II.
- Wrapping Materials:
- MIL-PRF-81705, Type II, or
- MIL-PRF-81705, Type III.
- Cushioning Materials:
- New Materials
- A-A-3129, Type I or II, Class 1 or 2, Grade B, [replaces PPP-C-1842] or
- PPP-C-795, Class 2, or
- A-A-59135, Class 1, 2, 3, or 5, Grade B, [replaces PPP-C-1752] or
- A-A-59136, Class 1, 2, 3, or 4, Grade B, Type I, III, IV, or V, [replaces PPP-C-1752] or
- PPP-C-1797, Type II [cancelled without replacement].
- Old Materials
- PPP-C-1842, Type III, Style A, or
- PPP-C-1842, Type III, Style B, or
- PPP-C-795, Class 2, or
- PPP-C-1752, Type VII, Class 1, Grade B, or
- PPP-C-1797, Type II.
- Unit Containers: refer to the requirements cited in the solicitation or contract
- Intermediate Containers: refer to the requirements cited in the solicitation or contract
- Marking: Special Marking Code = 39 - 'ESD sensitive electronic device requirements of MIL-STD-129 apply' (Refer to the MARKING FAQ web page for more details)
- How can I determine if I bought the correct barrier material?
Military barrier materials are identified by their markings. For determining if you actually received MIL-PRF-81705, check for the following information. Two groups of markings are used to identify the material.
- The first group include:
- Specification number
- Type
- Manufacturer's name
- Manufacturer's designation
- Month and year of manufacture
- Lot number
- The second group identifies the protective qualities:
- Type I - EMI/STATIC SHIELD
- Type II - ANTISTAT
The two groups appear sequentially, running the length of the barrier, with 1 inch space between the groups. A complete group of markings will appear every 6 inches of the roll width or flat cut sheets. When the material is used to make bags, both groups of markings must be visible.
NOTE: Authorized manufacturers of MIL-PRF-81705 can be found within QPL-81705. ASSIST has this document on their web site.
- Should I cushion a circuit card assembly (or an item with sharp protrusions) with approved cushioning materials before placing it into MIL-PRF-81705?
Yes. We highly recommend items be first cushioned with the approved ESD materials, then placed within a MIL-PRF-81705 barrier bag and heat sealed. This process will ensure the packaged item will not puncture the barrier bag and not compromise the ESD protective barrier during transportation and handling. The DoD distribution system is very diverse the degrees of severity during its handling and transportation modes. Should an item's ESD protective barrier be compromised for this reason, our customers and/or depots will file a complaint reporting your company as being non-compliant. We, in turn, will contact your company requesting replacements of the material which are properly packaged in accordance with the contract packaging requirements. In addition, to either potentially or delaying a mission, decreasing stock readiness levels, and reducing customer satisfaction, the complaint will also affect your company's ABVM rating.
- Are special procedures required when handling ESDS items?
Yes, guidelines for handling ESDS items are provided in MIL-STD-1686 and MIL-HDBK-263.
- Do I need a special workstation?
Yes. All handling and packaging of ESDS items shall be performed at a protective workstation. If this is not possible, the ESD protective field service kit MUST be used.
- What does a ESD protective workstation consist of?
There are different types of ESD protective workstations. The following are some of the available ESD protective workstations:
- 4240-01-087-3458: Static Control Work Station Components (contains 4 ft. x 6 ft. foot floor mat with 15-foot ground, cord, table mat, wrist strap, and 5-foot bonding cord).
- 4940-01-250-4236: Work Station, Electrostatic Control (contains a static dissipative soft table mat, common point ground system, and wrist strap with current limiting resistor; to be used in all areas other than clean rooms or laminar flow booths where ESDS items are handled; includes a small/medium and a large/extra large wrist strap cuff).
- 4940-01-250-4237: Work Station Kit, Electrostatic Control (contains a static dissipative portable work surface, common point ground system, and wrist strap with current limiting resistor;for situations where other static control used in workstations are not available; includes a small/medium and a large/extra large wrist strap cuff).
- 4940-01-250-4238: Work Station Kit, Electrostatic Control (permanent technical workbench or table with static dissipative work surface; may be used in any area where ESDS items are handled. This is a specification for work surface only. Wrist straps and a common point grounding system must be added).
- If your ESD workstation does not include a wrist strap - you need to order: 4240-01-063-4880 (wrist strap 36 inches in length with 250K resistor)
- What does a ESD protective workstation look like?
The following link provides a good illustration of an ESD protective workstation, identifies the various parts, and provides manufacturing and handling tips.
- What does a ESD field service kit consist of?
An ESD protective field service kit (5920-01-253-5368) consists of the following:
- 3 each - pouch, MIL-DTL-81997, Type II;
- 3 each - Bauer bag, MIL-PRF-81705, Type I;
- 2 each - wrist strap;
- 1 each - ground cord; and
- 1 each - mat, static dissipating.
- Are there any special markings for ESD items?
Yes. Visit our Marking FAQ web page for details.
- Where can I get further training on the Packaging and Handling of Electrostatic Discharge Sensitive items?
The School of Military Packaging Technology (SMPT) offers on-site, resident, and correspondence courses covering 'Packaging and Handling of Electrostatic Discharge Sensitive Items' (SMPT-6).
Content Inquiries: DSCC.Packaging@dla.mil
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