Packaging
Depending upon the application, different levels of ESD protection may be required. To specify the best product for a particular task, the correct level of ESD protection should be assessed.
In accordance with BS EN 61340-5-1, these levels are directly associated with the application. As a result, packaging and handling products can be grouped into three main categories as shown below:
Intimate Packaging:
These packaging materials come into direct contact with electrostatic sensitive devices (ESDS). They must be low charging and electrostatic dissipative or low charging and electrostatic conductive as specified in BS EN 61340-5-1.
Proximity Packaging:
Acting as an electrostatic shielding mechanism, proximity packaging is used to transport or store ESDS in uncontrolled conditions. It must be capable of dissipating electrostatic charges and of providing a path to Ground.
Secondary Packaging:
This represents all additional packaging required to provide mechanical or physical protection. Where it is used in conjunction with intimate and proximity materials and its’ electrostatic properties are not a major consideration, it must not be taken into the EPA area. For applications requiring ESD safe secondary packaging, conductive container systems and vacuum formed materials are available.
STANDARD TERMS ARE ALSO DEFINED AS FOLLOWS:
LOW CHARGING
Packaging that exhibits properties which minimise any charge generation (historically called ‘antistatic’)
ELECTROSTATIC DISCHARGE SHIELDING
Barrier or enclosure that limits the passage of current and attenuates the energy resulting from an electrostatic discharge such that the maximum energy from 1000V human body model discharge is less than or equal to 50nJ.
ELECTROSTATIC CONDUCTIVE
Packaging with a surface resistance (Rs) ≥1x10^2 Ω and <1x10^5 Ω
ELECTROSTATIC DISSIPATIVE
Packaging with a surface resistance (Rs) ≥1x10^5 Ω and <1x10^11 Ω
INSULATING
Packaging with a surface resistance (Rs) ≥1x10^11 Ω
TRIBO-ELECTRIC CHARGING
Electrical charging process in which charge is generated by the contact and separation of two surfaces, which may be solid, liquid or particulate-carrying gasses.
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