5 Essential Tips for Using ESD Shielding Bags
Selecting the right ESD bag is only the first step; equally important is understanding how to use it correctly to protect your sensitive devices. Although we’ll use shielding bags as an example, these tips apply to all types of ESD bags.
Here are 5 essential tips to help you make the most of your ESD shielding bags.
1. Enclose Your ESD-Sensitive Item
Ensure the entire product is enclosed within the shielding bag, making sure that the bag you have chosen is large enough to fit the entire ESD Sensitive item. the bag should then be sealed using tape, a label, or a zipper. This creates a continuous Faraday Cage, providing necessary electrostatic shielding. This is the only way to ensure ESD sensitive devices placed inside the shielding bag are protected. If you are unfamiliar with the term “Faraday Cage”, scroll to the bottom of this page – we’ve included a more detailed explanation at the end of the post.
Tip: Never staple a shielding bag, as this can puncture the shielding layers, providing a conductive path from the outside of the shielding bag to the inside. Charges outside the shielding bag could potentially charge or discharge to ESD sensitive components inside the shielding bag, compromising its effectiveness.
2. Remove Charges Before Opening
When receiving an ESD sensitive device enclosed in a shielding bag, place the shielding bag on an ESD-safe work surface before removing the product. This step neutralizes any static charge that may have accumulated on the bag's surface.
3. Avoid Overusing Damaged Bags
Reusing shielding bags is acceptable if they are free of holes, tears, or excessive wrinkles. Damaged bags should be discarded as they no longer provide adequate protection.
4. Don’t Use Shielding Bags as a Work Surface
Although a shielding bag is safe to use around ESD susceptible products, they are not intended to be a substitute for an ESD work surface. Use a properly grounded ESD-safe surface for handling sensitive devices.
5. Shielding Bags Are Not Gloves
Do not use shielding bags as “ESD potholders” or ESD safe gloves. This type of use offers no ESD protection to the product. Instead, ensure you are grounded using wrist straps or heel grounders for safe handling.
Understanding the Faraday Cage Effect
A Faraday Cage or Faraday shield is an enclosure formed by conducting material or by a mesh of conductive material. Such an enclosure blocks external static and non-static electric fields. Faraday Cages are named after the English scientist Michael Faraday, who invented them in 1836.
An impressive demonstration of the Faraday Cage effect is that of an aircraft being struck by lightning. This happens frequently but does not harm the plane or passengers. The metal body of the aircraft protects the interior. For the same reason, a car may be a safe place during a thunderstorm.
In ESD Protection, the Faraday Cage effect causes charges to be conducted around the outside surface of the conductor. Since similar charges repel, charges will rest on the exterior and ESD sensitive items on the inside will be ‘safe’.
Examples of ESD control products that provide a Faraday Cage or shielding include Metal-In and Metal-Out Shielding bags.
When to Use ESD Shielding Packaging
ESD shielding packaging is essential when transporting or storing sensitive items outside an ESD Protected Area (EPA). Per Packaging Standard ANSI/ESD S541 clause 6.2 Outside an EPA “Transportation of sensitive products outside of an EPA shall require packaging that provides:
- Low charge generation.
- Dissipative or conductive materials for intimate contact.
- A structure that provides electrostatic discharge shielding.“
