We had an ISO finding where paper was on top of circuit boards and I am trying to convince management to invent in ESD sleeves for our production process. Management isn’t happy with the pricing of the ESD sleeves and are wanting to find an alternate solution without drastically changing our current process. I know I have read that paper touching pcb/sensitive devices is a risk and i’ve seen the documents for specs on ESD sleeves. Do any of the standards specifically state the requirements for regular paper if it is going to be next to a pcb? I was thinking that the requirement would be that the paper would have to be inside a ESD package that would contain any static buildup and had to be sealed on at least three sides. One of the suggestions I was given was an ESD clipboard, but the paper would be completely exposed on the top
Would it be possible to use the static shielded bags or the cheap pink antistatic bags? The paper would go inside and that would be placed directly on the circuit board or between two circuit boards.
Josh,
There is no specific ESD requirements for paper on top of circuit boards other than the requirement in ANSI/ESD S20.20, section 8.3.1 on insulators:
• Measure the field at the location where the ESDS item is handled. The electrostatic field shall be less than 5000 volts/meter (125 volts/inch).
or
• For any process essential insulators located less than or equal to 25 mm from an unprotected ESDS item, the voltage on the surface of the insulator shall be less than 125 volts when measured with a non-contact electrostatic voltmeter. When using an electrostatic field meter, the reading shall be less than 125 volts when measured at the meter’s stipulated measuring distance.
• For any process essential insulators located more than 25 mm, but less than 300 mm from an unprotected ESDS item, the voltage on the surface of the insulator shall be less than 2000 volts when measured with a non-contact electrostatic voltmeter. When using an electrostatic field meter, the reading shall be less than 2000 volts when measured at the meter’s stipulated measuring distance.
Most paper have resistances under the insulative range (<10^9 ohms), but you should always verify it.
Since you intend on putting the paper on the circuit board, I recommend using the first method. If you measure the electric field at the circuit board, with the paper present and you don’t see anything over 125 volts/inch, you should be fine
Josh,
Another thing to consider are the requirements listed in ANSI/ESD 541
6.1 Inside an EPA
Packaging, when used within an EPA, shall be:
• Low charging (see 7.1)
• Dissipative or conductive for intimate contact with ESDS items.
6.2 Outside an EPA (UPA)
Transportation of ESDS items outside of an EPA shall require packaging that provides:
• Low charging (see 7.1)
• Dissipative or conductive for intimate contact with ESDS items.
• A structure that provides electrostatic discharge shielding.
I am not quite sure what application you are trying to achieve - but the concept from S541 I believe would apply.
There are also suppliers that make/sell ESD paper as well. You could look them up.
I would not recommend the use of static shield bags as charges may tend to reside on the outside of the bag. you would definitely have to measure this.
I would also not recommend pink poly types of materials as they tend to lose their dissipative properties over time. Also, because of the manufacturing process of pink poly, there is a chance that the material may off gas which could cause you contamination problems.
Late to the party, but a couple of thoughts:
- If you go with the “ESD Safe” sleeves, do testing on some frequency to verify they are still measuring appropriately. We have recently found that some of our sleeves fell out over time. Some manufacturers use a topical or other type of additive to improve the characteristics of the material. This can lose its effectiveness.
- No matter what way you go, make sure employees are not placing the paper, sleeve, bag… between the ESDS and the grounded surface when they place them on a workstation…
You are absolutely right, CAlmeras.
Stright seeing only to standards causes a lot of troubles. Practice, however, leads along the paths of life. Customer, especially auditor, is always right and arguing with such kind of breadwinner for bussines brings bad finish 
Why does customer afraid papers within EPA? That the first reason. Sometimes it is no knowledge enough. But only sometimes and from today’s point of view, such things were years ago.
Regards