With electronic components growing smaller and more sensitive, it is important to make sure they are protected against ESD events including static discharge. Per ANSI/ESD S20.20, “Protective packaging is required to store, transport, and protect ESDS electronic items during all phases of production.” Per the updated 2018 requirements for ANSI/ESD S541, shielding requirements were updated such that subsequent discharge for the bags should be under 20 nanojoules. The Pink Poly bag is one of the more common low charging bags. The bags are made with a tinted polyethylene material with an antistatic coating which may wear away. Over time, this makes the bag become an insulator, as such, it is no longer compliant to ANSI/ESD S541 recommendations. These bags are also missing discharge shielding protection that allows components within the bag to be susceptible to ESD event damage. Metallized Shielding bags are constructed from a metalized polyester film and a low charging polyethylene laminate. This provides them with a shielding layer that creates a Faraday cage that protects the ESD-sensitive components inside the bag from possible ESD event damage. The low charging inner layer and outer layers of the bag prevent tribocharging from occurring, limiting the buildup of ESD charges when handling components.
Have you ever been questioned about the shelf life of ESD bags by your quality manager? Maybe it is an internal quality procedure being written and you’d like to know the manufacturer’s position on the shelf life of ESD packaging. Well today we’ll look at the topic of ESD Static Control bag storage and the expected shelf life. There are 1000’s of variations to consider when discussing shelf life. Heat, conditions of the storage rack, how it was transported, even local climate just to name a few, so the key points are:
- Avoid extremes: heat, cold, sunlight, moisture, add controls when possible
- In a controlled environment, our ESD bags have seen 5 years of provable shelf life.
- As a best practice, follow the FIFO process for inventory control.
- ESD static bag manufacturers that we represent offers a 1 year warranty from the date of purchase. Be sure to audit every year or before use as a best practice and to be sure that your devices are receiving the best possible protection.
- If bags are questionable, recycle the bags at your local recycling center and order more from Restronics Northern California.