2021

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A Simple Demonstration on the Differences Between a Pink Poly Antistatic Bag and a Static Shielding Bag

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Fairly regularly we are seeing low charging or antistatic Pink Poly bags being used for the wrong application. These bags are made from a tinted polyethylene material with an antistatic coating that can wear away. This turns the bag insulative and high charging over time, making it noncompliant to ANSI/ESD S541 recommendations.

They also lack discharge shielding protection which makes components within the bag susceptible to ESD event damage. It is this distinction that is most important – as Pink Poly bags don’t provide shielding, they should not be used to carry ESD Susceptible (ESDS) items outside the EPA, i.e. when the sensitive item isn’t grounded. Per ANSI/ESD S541-2018, Table 1. ESD Protective Packaging Requirements by Location, Discharge Shielding is Required for Outside the EPA (UPA).

SCS Metallized Shielding bags are constructed from a metalized polyester film and a low charging polyethylene laminate. This provides the bags with a shielding layer that creates a Faraday cage protecting the ESD sensitive components within the bag from possible ESD event damage. The low charging inner layer and outer layer of the bag prevent tribocharging from occurring, minimizing the build-up of ESD charges when handling components. This low charging layer is longer lasting than a pink antistatic bag.

Per ANSI/ESD S541-2018 – Table2. Summary of ESD Protective Properties

“Discharge Shielding“

“Protects packaged items from the effects of static discharge that are external to the package and limits current flow through package”

Per ANSI/ESD S541-2018 – Per 7.3.1 Electrostatic Discharge Shielding

“Electrostatic discharge shielding materials are capable of attenuating an electrostatic discharge when formed into a container such as a bag”

Watch our video for a simple demonstration on how pink poly bags differ from static shielding bags:

For more information on the differences between these two materials, and a demonstration on how to test per ANSI/ESD S11.31 and ANSI/ESD S541 visit this page.

Static Shielding Bags
EM EYE – ESD Event Meter
770716 – Static Sensor

A Minute with Miranda – Charge-Guard™ ESD Surface and Mat Cleaner Wipes

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Welcome back to “A Minute with Miranda.” This week we will be covering how to clean your ESD Worksurface Mat.

For optimum performance, the ESD worksurface mat should be cleaned regularly using a recommended ESD mat cleaner. Per the ESD Handbook ESD TR20.20, “Ensure that cleaners that are used do not leave an electrically insulative residue common with some household cleaners.” We recommend using Charge-Guard™ ESD Surface & Mat Cleaner Wipes to clean and maintain ESD mats and other worksurfaces. Charge-Guard™ wipes do not contain silicone or other substances that will leave an insulative residue or inhibit the performance of an ESD surface.

It is recommended to test the surface after cleaning to ensure that all insulative contaminants such as dirt and grime have been removed. Charge-Guard™ ESD Surface & Mat Cleaner Wipes will only leave behind a coating with a surface resistance of less than 1 x 10^9 ohms.

8004 - Charge-Guard™ ESD Surface and Mat Cleaner, 25 Wipes
8004 – Charge-Guard™ ESD Surface and Mat Cleaner, 25 Wipes
SHOP OR REQUEST A SAMPLE OF CHARGE-GUARD™ WIPES

New to ESD Control and need help to set up a Workstation?

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Implementing ESD control measures can be very simple, particularly if you are starting with one or two workbenches. Each workbench would be an individual ESD Protected Area (EPA) and when ESD Sensitive (ESDS) devices are not at the ESD workbench they should be in a closed ESD shielding container or bag. In today’s blog we provide a basic set up for a start-up workbench EPA.

Personnel Grounding

Single-Wire Wrist Straps

Adjustable Wrist Strap, Blue, with 6′ Coil Cord

One size fits all adjustable wrist band with coil cord is used to ground a stationary operator.

4 mm snap, 1 megohm resistor

Meets ANSI/ESD S20.20 and ANSI/ESD S1.1

ECWS61M-1

One size fits all blue adjustable single-wire wrist band with 6-foot coil cord

Static Control Garment

Smock Jacket with Knitted Cuffs, 3 Pockets, No Collar, Blue

Creates faraday cage effect around torso and arms of operator

Groundable static control garment systems meets ANSI/ESD S20.20 (Rtg < 3.5 X 107ohms) Requirement Tested Per ANSI/ESD STM2.1 and ESD TR53

Hip-To-Cuff Grounding – Improves productivity, grounds operator with no need for a cord to be attaches to the operator’s wrist

770012

Static Control Worksurface Mat Kits

R7 Series 2-Layer Rubber Mat Kit

Provides a worksurface that does not generate a static charge and will control the discharge rate from all conductors (including ESD susceptible items) that are placed on the surface

Includes table mat, LPCGC151M Common Ground Cord and 3049 Snap Kit

Dissipative Dual Layer Rubber Material

High Strength Nitrile Rubber Compound – Constructed to withstand abrasion, tearing and may be used in soldering applications with flux and other chemicals.

770776 – 770784

ESD Surface and Mat Cleaner

Charge-Guard™ ESD Surface and Mat Cleaner, 25 Wipes

Ideal for Use After Sanitizing an ESD Worksurface with Alcohol

Removes dust, grease, grime, fingerprints, solder flux and other contaminants from ESD mats and other surfaces

Alcohol-Free Formula – Excessive use of alcohol-based cleaners may dry-out mats (vinyl or rubber) and degrade performance

8004

8004 -Charge-Guard™ ESD Surface and Mat Cleaner, 25 Wipes
770031- Combo Wrist Strap and Footwear Tester with Stand

Wrist Strap and Footwear Tester

Combo Wrist Strap and Footwear Tester with Stand

Tests operator’s resistance loop; wrist strap limits 750 kilohms to 10 megohms; footwear limits 750 kilohms to 100 megohms – Determines that operator’s personal grounding device is functioning correctly.

Separate test circuits for wrist straps and foot grounders

Use with Single-Wire Wrist Strap

770031

Surface Resistance Meter

Resistance Pro Meter Kit

Tests Digital Compliance Verification Surface Resistance Meter Kit – Measures resistance point-to-point (Rtt) and resistance-to-ground (Rtg) of worksurfaces, flooring systems, garments, packaging, and other materials in accordance with ESD Association documents: ESD TR53, ANSI/ESD S4.1, ANSI/ESD S7.1, ANSI/ESD STM97.1 and others

Internal Memory – Stores and recalls up to 100 measurements. Captures resistance, temperature, humidity and test voltage.

770760

770760 - Resistance Pro Surface Resistance Meter Kit
1000 Series Metal-In Static Shield Bag

Static Shielding Bags

1000 Series Metal-In Static Shield Bag

Metal-In Film Laminate 0.0028” thick (2.8 mil) – Protects ESD sensitive contents from electrostatic fields and electrostatic discharges (ESD)

<10 nJ Discharge Shielding Energy Limit Test per ANSI/ESD STM11.31 – Meets ANSI/ESD S20.20 and ANSI/ESD S541 requirements for ESD shielding packaging inside and outside an ESD Protected Area (EPA)

1000 Series

Conclusion

Whilst this guide provides a high quality but manageable avenue into ESD Control, not all ESD Programs are created equal, every company has different processes. So, get in touch with your requirements or complete our Checklist and SCS will support with a custom qualified parts list based on your application.

Get in Touch!

Need Help with ESD?

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Need Help with ESD?

Perhaps you’ve come across this blog post because you find yourself asking:

  • Is my ESD Control Program in compliance?
  • Is ESD costing my company too much time, money or even future business?
  • I’m new to ESD control and don’t know where to start?
  • My company needs to start taking ESD precautions, what do I need for a basic set-up?
  • I am sure we are compliant to ANSI/ESD S20.20, but how can we confirm that?

Complete our ESD Program Checklist to start getting the answers to these questions and more:

ESD CHECKLIST

What You Should Know Before Using ESD Laminate and Continuous Monitors

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There are all kinds of variations and combinations of ESD Laminate and Continuous Monitors used by companies with ESD Programs.. There are some key factors that you need to be aware of if you intend to use ESD Laminate together with a continuous monitor that will monitor the worksurface connections.

It’s important to note that continuous monitors don’t monitor the status/condition of the outer surface of an ESD workstation. The continuous monitor monitors the connection between groundable points on the worksurface (often snaps), not the Resistance to Ground (RTG) of the surface itself. The RTG measurement must be taken separately, per ANSI/ESD TR53-01-18 – Compliance Verification of ESD Protective Equipment and Materials (Pages 6 and 7).

The basic technology is that the monitor applies a low test voltage to the scrim layer in the worksurface. Because the test voltage is so low, the resistance of the scrim layer of the mat must also be low so that the test voltage can complete a circuit of the scrim layer, worksurface connections (snaps) and ground cords. Completing that circuit indicates that the worksurface is electrically connected. The goal is to have the worksurface circuit fail because of a bad connection, not because the scrim layer resistance was too high.  As mentioned earlier, testing the combination of the outer layer and the scrim layer together (RTG) is a separate test.

When choosing a continuous monitor and worksurface combination that will work together it is important to consider the following:

  • Does the worksurface have a separate scrim layer? (vs. a homogenous mat material)
  • Does the continuous monitor spec sheet note the resistance limit of the scrim layer required for the monitor/worksurface alarm system to pass?
    • See the excerpt below from the SCS 724 Continuous Monitor Technical Bulletin – https://www.descoindustries.com/PDF/724-Workstation-Monitor-User-Guide.pdf
      “Red Worksurface LED (M) This indicates that a high resistance condition (> 3.7 Megohms) exists across the conductive layer of theworksurface and/or the ground connections. Check the worksurface, ground cords and their connections for continuity. Note the audible alarm may also sound if enabled.”

What this means is if the resistance of the mat scrim layer is greater than 3.7 Megohms then the continuous monitor mat alarm would alarm for a high resistance condition even if the grounding hardware connections to the worksurface were intact. There are other SCS monitors available that will monitor a scrim layer with a resistance as high as 5 x 108.

In summary, it’s critical to know both the upper limit of the “pass” condition of the continuous monitor and the construction of the worksurface material (does it have a scrim layer and if so what is the resistance of the scrim layer?)

ESD Laminate requires extra attention when being considered for use with a continuous monitor for the following reasons:

  • Laminate material is rigid, which makes it more difficult for grounding hardware to make a good contact with the scrim layer.
    • Consider abrading the outer, decorative surface to expose the scrim layer for better contact. Consider a flat bottom drill for this process.
  • Most importantly, perform a test on the resistance between two points on the worksurface to determine if the resistance meets the requirements of the specified monitor (for the SCS 724 that requirement is less than 3.7 Megohms – 3.7 x 106 ). We recommend using an ohm meter with a test voltage similar, if not identical to the test voltage used by the continuous monitor. We recommend performing this test before the purchase/installation of any number of continuous monitor/worksurface combinations.