In regards to ESD Safe Tools (Tweezers, Vacuum Pick-Up Tools, etc.) what level of documentation / certification do we need to maintain for ESD compliance? Is it necessary to obtain certification to ESD specs from the tool manufacturer to document compliance to ESD standards or can we test and/or audit internally?
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Hello and welcome to the forum.
There are two responses for this question. First answer is easy. For product qualification of ESD control items there are three ways they can be qualified. They are:
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Product specification from manufacturer
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Independent laboratory evaluation (third party)
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Internal laboratory evaluation
All these items require testing to table 2, 3, or 4 in ANSI/ESD S20.20 - 2021 which call out specific standards.
Second answer is more specific to your question. Items that you have listed tweezers, vacuum pick-ups and other item, are not listed in the table. In this case, qualification is up to the user to determine. For something like tweezers, there may be a requirement for the tweezer itself but it is used with a person, so a quick resistance to ground check while holding the tweezer may be enough.
If you have any further questions, please feel free to post.
Hi John,
please,
“…there may be a requirement for the tweezer itself but it is used with a person, so a quick resistance to ground check while holding the tweezer may be enough”
What resistance value should we measure between the tip of the tool through the person and the ground? a value of <1x10e9 ohm can be the reference ?
Many thanks
GS
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The ESDA is currently working on a technical report on the evaluation of non powered hand tools. We encourage anyone interested to join us at the Standards meetings. This TR falls under working group 13.
For a reference 10^9 for a system measurement including the operator is a good starting point, some may use up to 10^11 depending on what they are working on. Checking the resistance of the tool tip itself is another check to perform. Very low resistance tips can provide their own problems. The other consideration would be the sensitivity of the components/product being processed.
Hi CAlmeras,
many thanks for quick answer.
GS
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No problem. Glad to see others taking interest in the topic of hand tools. It tends to be a forgotten item in controls.
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** As of now, neither of the two global standards ( ANSI/ESD S 20.20.2021 & IEC61340-5-1-2016) have any specific Information defined on the evaluation of hand tools like Brushes-Tweezers- Pliers etc, except the one on Soldering /De soldering per ANSI/ESD S.20.20.2021 **
However; there are some procedures in IEC TR 61340-5-4 a technical report in support to IEC 61340-5-1 (though not defined specifically in this ) for evaluation of hand tools that could be used. The main idea is to measure the resistance of the person holding the tool to ground. Generally, a loop resistance measurement from the hand, through the tool, to a metal plate. This technique can be applied to brushes, tweezers, and most hand tools. Some tools can be measured for electrical resistance using a two-point probe or static decay using a charged plate monitor. The application test mentioned above gives the most meaningful information about the actual performance of the hand tool.
Few months before there was a Tech-talk (webinar ) from ESDA on the hand tools testing topic . The recorded version can be viewed on ESDA site www.esd.org
As Chris stated, ESDA is working on a hand tool document. Until that time, consider what is in ANSI/ESD S20.20. First of all if the tool has a metal tip, measure the tip to ground resistance as in use. If it is less than 1x10e9, not really a problem. If greater than 1x10e9 and the tip comes into contact with an ESD senstive item, then it could be treated as an isolated conductor. In that case, see if it is a threat. A threat with an isolated conductor is a tip which has a voltage greater then 35 volts or less than -35 volts.
Use these guidelines for evlaution of hand tools that come into contact with ESD senstive items.
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Hello,
As per me regularly scheduled internal audits and tests should be conducted according to established ESD standards, and detailed records of these tests should be maintained. These records should include information on the methods and equipment used for testing, as well as the results. This approach allows for ongoing verification that ESD tools remain compliant over time, ensuring consistent protection against electrostatic discharge.
Thanks