Category Archives: ESD Control Boxes
A Faraday cage or Faraday shield is an enclosure formed by conducting material or by a mesh of such 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 to be in a thunderstorm.
ESD control products that provide a Faraday Cage or shielding include Statshield® Metal-In and Metal-Out Shielding Bags, Protektive Pak™ impregnated corrugated with shielding layer when using a lid, and Conductive Totes. Statshield® ESD Smocks creates a Faraday Cage effect around the torso and arms of the operator and shields charges from the operator’s clothing from damaging ESD sensitive devices. (Technically, suppressing the electrical field from clothing worn underneath).
There are standard tests measuring the energy penetration of electrostatic discharges to the interior. The Shielding test method per Packaging standard ANSI/ESD S541 is ANSI/ESD STM11.31 and the required limit is less than 50 nanoJoules of energy.
ESD shielding packaging is to be used particularly when transporting or storing ESD sensitive items outside an ESD Protected Area. Per Packaging standard ANSI/ESD S541 section 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.”
Definitions from the ESD Association Glossary ESD ADV1.0 include: Faraday cage “A conductive enclosure that attenuates a stationary electrostatic field.”
Electrostatic discharge (ESD) shield “A barrier or enclosure that limits the passage of current and attenuates an electromagnetic field resulting from an electrostatic discharge.”
Electrostatic shield “A barrier or enclosure that limits the penetration of an electrostatic field.”
Note: the ESD Association sells most documents, however, the Packaging standard ANSI/ESD S541 and the Glossary ESD ADV1.0 are free downloads from www.ESDA.org (click Standards and then Documents, scroll down to find documents that can be downloaded at no charge).
Protektive Pak’s Dissipative Impregnated Corrugated material features a unique characteristic, a buried shielding layer. This provides a better value because unlike dissipative or conductive painted material, the buried shielding layer will not rub/scratch off or lose its ESD properties. This translates into a superior, longer lasting ESD safe package.
Third party testing has been performed on Protektive Pak’s Impregnated Corrugated material demonstrating that the buried shielding layer in our corrugated material provides a better value than dissipative or conductive coated (or painted) material.
- Protektive Pak impregnated corrugated material has a buried shielding layer
- Protektive Pak impregnated corrugated material equals or exceeds the discharge shielding capabilities of a coated box
- Protektive Pak impregnated corrugated material has discharge shielding capabilities equal to a metal-out shielding bag
- Protektive Pak Dissipative Corrugated Material meets the ANSI/ESD S541 recommendation, avoiding rapid discharge when contacting ESD sensitive items –
conductive coated boxes DO NOT!
Protektive Pak Dissipative Impregnated Corrugated Material meets ANSI/ESD S20.20 and Packaging standard ANSI/ESD S541 tested per ANSI/ESD STM11.11 and modified ANSI/ESD STM11.31
For complete third party test results, click HERE.
Watch our Material Test video:
“Returnable Packaging,” as defined by Returnable Packaging Association (RPA), is packaging which includes “…reusable pallets, racks, bulk containers, hand-held containers and dunnage that move product efficiently and safely throughout the supply chain. Reusable packaging is typically used by manufacturers/processors and their suppliers/customers in a well-organized supply chain, with very tightly managed shipping loops.”
So what does this mean? Returnable packaging is manufactured of durable materials and is specifically designed for multiple trips and extended life.
When a vehicle leaves a facility to drop off product and then returns to pick up more product, you have what is called a “milk run”. Milk runs are perfect for returnable packaging.
Utilizing returnable packaging cuts down on material costs as well as total cost. There is much less need for repeated purchasing of disposable containers. The money saved will now go towards your profit line! In addition, returnable packaging cuts down on waste by re-using packaging rather than just using it once and throwing it away. No more dumpsters full of unneeded waste!
Protektive Pak In-Plant Handlers are a great choice for reusable packaging. Made to protect ESD sensitive components, the boxes are constructed with double thick sides and double or triple thick ends and are extremely durable. They withstand the abuse of transporting. After transporting product to another facility, the boxes can be reused to ship more product or collapsed and stored for future use.
ElectroStatic Discharge (ESD) is silent, quick and potentially lethal to electronic parts. When electronic parts are not properly handled during manufacturing, assembly, storage, or shipping, damage from ESD can reach into the millions of dollars each year.
For an ESD control container to be effective against ElectroStatic Discharge, it must possess certain electrical characteristics:
- Surface resistance <1 x 1011 ohms per ANSI/ESD STM11.11
- Energy penetration <50 nanoJoules per ANSI/ESD STM11.31
Non-shielding containers might be cheaper, but they are not less costly when it comes to handling ESD sensitive items. Anytime ESD sensitive parts and assemblies are handled, regular containers are not a sound option, even part of the time, as the risk of ESD damage is always lingering. As a result, costs will be incurred, either via ESD damage or as an additional investment in discharge shielding packaging and material handling containers.
The disadvantages of cross-using shielding and non-shielding containers include:
- Increased cost
- Risk from ESD damage
- Handling inconvenience
The cost of a discharge shielding container is far less than the cost associated with damaged parts or extra handling that result with a “less expensive” non-shielding container.