17 Dec

Do You Need Static Control Flooring?

Do You Need Static Control Floors?

Does your business have a substantial investment in electronics or computers?

Have you ever experienced an unexplained failure? Perhaps one of your critical systems went down with no warning at a critical time (there’s never really a convenient time for that, is there?), or perhaps a component was working beautifully one minute and performing erratically the next.

One of the most nefarious—and hardest to detect— culprits behind failures of this kind is electrostatic discharge. By some estimates, it could be responsible for more than fifty percent of hardware failures, costing upwards of $5 billion each year.

So, if you have devices, people, and floors, then you face risks from the devastating effects of static electricity—specifically electrostatic discharge (ESD).

How Can Floors Protect Equipment from ESD Damage?

Since static control flooring provides an attractive “escape route” for static electricity that builds up in the most common of circumstances, it can be a relatively simple and inexpensive way to protect your valuable data & devices from getting zapped.

Aren’t specialized static control floors ugly?

If the thought of specialized protective flooring conjures up images of server rooms, data centers, or ugly hospital wards, then we’ve got good news!

Today, ESD floors come in an amazing array of materials, styles, and colors. Sure… we install rubber floors. We epoxy concrete.

But we also have attractive broadloom carpet that provides decent ESD protection for your sensitive electronics in beautiful designs—so beautiful, in fact, that no one would ever suspect that the carpet is actually serving a valuable purpose beyond that of ordinary carpet!

In addition to broadloom carpet, we also carry carpet tiles and vinyl tiles and sheet flooring. Each is suitable for different situations, and they are available in configurations that provide varying degrees of protection depending upon your specific situation.

Which Static Control Floor is Right for You?

Whether you run a manufacturing facility or a cubicle farm, a call center or a clean room, the fantastic assortment of options available today means that you can find a flooring solution that meets your needs. Obviously, there are a number of factors involved in making the right decision.

Some of the considerations you’ll need to include in your decision-making process include:

  • Durability: Will the floor be in a high-traffic area? The volume of foot traffic will certainly affect how long your floor will last, and therefore should be considered as part of the overall cost of ownership.
  • Maintenance: Since your floor contains components—from conductive carpet fibers to embedded veins of specialized materials—to give static electricity a place to go, you’ll want to weigh out the maintenance needs of the flooring.
  • Static Control Performance: ESD flooring comes in various levels of effectiveness (measured by its “conductivity”). How conductive or dissipative your floor needs to be depends upon the nature of your equipment, the installation environment, and the nature of the usage.
  • Other Factors: Does the floor need to help absorb sound to help control the noise in the environment? Do you need slip protection? What chemicals might be spilled on your floor?

As you can see, the flooring choices available to you can be a bit of a dizzying maze. But there’s good news: we’re here to help you navigate! Reach out today, and let our team of experts help you find the most effective solution at the right budget to match your situation perfectly!

14 Sep

Dissipative vs. Static Conductive Flooring: Which Works Best?

Dissipative vs. Static Conductive Flooring: Which Works Best?

Previously, we talked in greater detail about how ESD flooring works. But when it comes to choosing what type of static control flooring to use, the biggest question you need to answer is this:

Should I use static dissipative flooring or static conductive flooring?

Perhaps the most important factor you’ll need to consider in making this decision is safety.

Shouldn’t I Always Choose the Fastest Pathway to Ground?

At first glance, it might seem like a no-brainer: just put in the flooring that has the lowest resistance so that electrostatic discharge is carried most quickly and efficiency to ground. If that’s true, then static conductive flooring is an obvious choice.

But if the floor is too conductive, then we introduce another set of risks to personal safety.

This is where we start to get into safety standards developed by OSHA and the National Fire Protection Association (NFPA), among others.

Put simply, “static dissipative” flooring and “static conductive” flooring are two very specific classifications based upon levels of conductivity which is measured in terms of the materials’ resistance to electricity.

Resistance of ESD Flooring Options

Resistance, or impedance, is measurable, and is expressed in ohms. The ohm is a unit of measurement named after Georg Ohm, the German physicist who discovered Ohm’s law. In specifications documents, schematics, and other materials, the ohm is represented by the symbol Ω (the Greek letter omega).

Put simply, higher resistance = lower conductivity.

A substance with resistance measured at zero ohms (0 Ω) would highly conductive conductive (carbon, silver, and copper all have resistance measured in a fraction of an ohm). On the opposite end of the spectrum, a substance with 1 billion ohms (1 × 109 Ω) would have very low conductivity (rubber, which is so resistive that it’s used as an insulator, has a resistance in the 1.00×1013 Ω range, or 10,000,000,000,000 Ω, AKA ten trillion ohms).

In general terms defined by the ESD Association, “conductive” is describes any flooring with a resistance of up to 1 million ohms. “Dissipative” is used for anything greater than 1 million ohms and up to 1 billion ohms. 

ESD Flooring Type Resistance (Ω) Range (Low End) Resistance (Ω) Range (High End)
Static Conductive 1 × 106
Static Dissipative 1 × 106 1 × 109

Unfortunately, these categories are so broad that they aren’t entirely useful.

Thankfully, the ANSI 20.20 specification helps clarify things for us. It indicates that the maximum resistance of the flooring and the person (measured together) should be less than 3.5 × 10ohms.

The NPFA has also specified that flooring should have no less than 25,000 ohms resistance. Below this number, the conductivity of the floor is considered to be too high and therefore unsafe due to risk of electric shock and other hazards.

As you can see, neither the minimum resistance specified by the NFPA nor the maximum specified by ANSI 20.20 lines up perfectly with our terms for “static conductive” or “static dissipative” flooring.

So… we’re left with making a selection based upon the specific needs of your industry. What is the application of the flooring? Will it be used in a clean room? Will it be used in electronics manufacturing? What are the considerations around flammable materials?

Other factors will affect the decision as well. Will the humidity and temperature of the environment be maintained within specific parameters? Both will affect conductivity, not just in the floor, but in the environment as a whole. What other building materials will be used?

Additionally, when specifying the levels of conductivity in flooring, there is a diversity in testing and measurement that exists which will cause test results to vary widely depending upon the methodologies used. It’s important to understand how these measurements will affect the final outcome where conductivity is concerned.

The Bottom Line?

There are a number of factors involved in the decision when you’re selecting between static conductive or static dissipative flooring. Our ESD control experts will be more than happy to help walk you through the decision-making process and the range of options available to you — both from a performance standpoint and from an aesthetic one. Contact us today!

07 Sep

How Does ESD Flooring Work?

How Does ESD Flooring Work?

When it comes to controlling Electrostatic Discharge in a commercial setting, one of the most important areas to address is the flooring. The floor is one of the single biggest surfaces, and almost every piece of furniture, major equipment, and even people will come into contact with flooring surfaces on a regular basis.

How does this impact your choice of flooring?

Well, obviously certain materials in carpeting are known to generate static electricity when the carpet fibers rub up against other materials, like the rubber in the soles of workers’ shoes. Since we quite obviously don’t want the flooring to make the ESD problem worse, we can rule out carpet that contributes to the buildup of static electricity.

This means that we start to look at the materials in the other available choices to see how they impact static electricity buildup and discharge.

Flooring & Electrostatic Discharge Pathways

It’s been said that electricity always follows the path of least resistance, but this is not actually completely true. Electricity will follow all available pathways when “circuits” are created (intentionally or not). The flow of electricity will, however, prefer pathways that have a lower impedance (resistance to electricity).

ESD flooring serves to create a preferred pathway for the flow of electricity, allowing the build-up of static electricity in devices, personnel, and equipment to have an immediate pathway to grounding.

Depending upon the situation, ESD flooring choices include ESD carpeting, ESD conductive tiles, or ESD dissipative tiles.

In the case of conductive tiles or ESD carpeting, the flooring materials contain conductive elements (e.g. carbon lines or conductive yarn fibers) that transmit electrical current through the flooring materials. ESD carpeting options are made with a conductive backing that helps facilitate this, whereas ESD tile is laid using a specially made conductive adhesive to adhere it to the subfloor. Current is then transmitted to conductive tape or copper strips placed beneath the surface of the floor.

Static Grounding Terminal - ESD Carpet

A static grounding terminal attaches one of our ESD carpet installations to a grounding point

From there, grounding is achieved by connecting the conductive materials below the ESD flooring directly to a grounding point, or by placing a special grounding tile at regular intervals which is, in turn, connected to a grounding point.

The ESD conductive tiles and ESD carpets are manufactured and tested to have minimal resistance to electrical current, which increases the likelihood that any static charge will pass through the flooring and on to ground instead of damaging sensitive equipment or igniting flammable or explosive substances.

ESD dissipative floors work in a similar fashion, but are engineered to have a higher resistance than flooring classified as “conductive.” This causes electricity to flow to ground in a slower, more controlled manner.

Which flooring should you choose? We’ll talk about that further in our next blog post. In the meantime, contact one of our static control experts to help you create the solution that’s perfectly tailored to your situation!

View Ground Zero's ESD Flooring Options!!

 

07 Jul

Are ESD shoes and Conductive shoes the same thing?

 

Q:

Are ESD shoes and Conductive shoes the same thing?

A: There are two types of ESD shoes, Static Dissipative and Static Conductive.

The Static Conductive shoe will guarantee a combined resistance of personnel and footwear of less than 1.0E6 Ohms.  I have a pair of Static Conductive shoes that when I’m standing on a static conductive flooring system (2.5E4 Ω to 1.0E6 Ω), my combined resistance from my body through the ESD footwear and through the ESD conductive flooring system to electrical ground or earth is less than 1.0E6 ohms per DoD 4145.26-M, C6.4.7.5.1: “The maximum resistance of a body, plus the resistance of conductive shoes, plus the resistance of the floor to the ground system shall not exceed 1,000,000 ohms total”… “The contractor can set the maximum resistance limits for the floor to the ground system and for the combined resistance of a person’s body plus the shoes, as long as the total resistance does not exceed 1,000,000 ohms.”

This Static Conductive shoe is typically used for electrical safety requirements for facilities that deal with explosive environments such as ordinance, munitions, explosive powders, flammable liquids, etc.  This is outside of the realm of ANSI/ESD S20.20-2007 and MIL-HDBK-263B.

If you’re goal is the protection of static sensitive devices, then Static dissipative shoes on a static conductive flooring system or a static dissipative flooring system will suffice so long as the combined resistance of personnel, footwear, and flooring to electrical or earth ground is less than 3.5E7 Ω as per ANSI/ESD STM97.1-2006.  In that case, a good static dissipative shoe will be more than 1.0E6 or a meg ohm, but the resistance will probably be less than 35 Meg ohms.  The best way to measure the footwear is to have personnel wear them for at least 10 minutes prior to going to the tester and checking for pass/fail low/fail high, as that’s the most practical way to test them.  You can measure the resistance of the shoe from insole to outsole, but they aren’t used that way on the ESD flooring system.  The ESD shoe relies on sweat from the personnel that wears them.

My combined resistance from my body, through my Static Conductive C4327 (men’s) or C437 (woman’s) shoes and through a static conductive floor to electrical/earth ground is about 7.0E5 Ω.  My combined resistance from my body through my Static Dissipative C4341 shoes and through a static conductive floor to electrical/earth ground is about 1.6E6 Ω.

I hope this answers your questions.  Please comment.

Thank you very much, Pat

Static Conductive shoe C4327 Resistance per ANSI/ESD STM97.1-2006

Static Conductive shoe C4327 Resistance per ANSI/ESD STM97.1-2006

0708090842

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Static Dissipative shoe C4341

Static Dissipative shoe C4341

18 Jun

We don't need no stinking wrist straps, do we?

Q: I have read the White Paper 1: A Case for Lowering Component Level HBM/MM ESD Specifications and Requirements and found the ESD Control Programs and Resulting Data (Chapter 1, Page 20-23) particularly interesting.

Assuming a production environment with ESD flooring, footwear (and clothing), by the time a person walks to a workstation and sits down, the voltage of this persons should not exceed 500V (or even 100V as seen in Figure 3). That would mean even a seated operator in this case would not need to wear wrist strap, that theory would be correct right? After sitting down and this person sits on a stool (feet off the floor) with resistance to floor < 1.0x10exp9ohms, any HBM risk would be further reduced wouldn’t it?

A: Hello ****.  Nice try.  Even if you have an ESD flooring system and even if you have ESD footwear and even if you have an ESD task chair with ESD casters or an ordinary task chair with an ESD chair cover (very effective as well), ESD smock on… you STILL have to wear the wrist strap when seated at an ESD workstation.

The only time, per ANSI/ESD S20.20-2007 page 4, 8.2 Personnel Grounding, that personnel in the EPA (ESD Protected Area) should be without a wrist strap is when doing standing or walking about operations, and then two conditions must be met;
·         “When the total resistance of the system (from the person, through the footwear and flooring to the grounding / Equipotential bonding system) is less than 3.5E7 Ω…”
·         “When the total resistance of the system (from the person, through the footwear and flooring to the grounding / Equipotential bonding system) is greater than 3.5E7 Ω and less than 1.0E9 Ω and the BVG is less than 100 v per 97.2…”

This is what is said about seated personnel:

“When personnel are seated at ESD protective workstations, they shall be connected to the grounding / Equipotential bonding system via a wrist strap system.”

Hope this helps.   I guess you could say redundancy is good in the realm of ESD.  It’s the weak link in the chain that will cause an ESD event.  If someone lifts their ESD footwear from the ESD flooring system while seated, they can tribocharge to above 100 volts.  It takes only 0.3 seconds of charge time to exceed 20.20 requirements.  If personnel is seated and getting up to go to break, it seems best to stand up, remove the wrist strap from the wrist, carefully set it down and walk away from the ESD workstation.  Worst case is to take the wrist strap off while still seated, set it down, put your hand on the ESD workstation and near ESDS devices, then stand up out of the task chair before leaving the work station.  Under proper conditions and with good bench mats, clean ESD floors, ESD task chairs, etc. in place, no ESD event.  The problem with ESD events is that we cannot see, hear, feel them.

The only alternative to not wearing a wrist strap while seated may be the used of a smock with a grounding coil cord attached to it.  You can see the footnotes on the 20.20 document at the bottom of page 4 for further details.

 We adhere to and meet or exceed requirements put forth in ANSI/ESD S20.20-2007 or IEC 61340-5-1, which assumes a target HBM of 100 volts and less.

05 May

Why 3.5E7 Ohms limit for flooring/footwear?

Q: Does anybody know the reason behind the upper limit resistance (3,5×10E7Ohms)of a grounding system (personnel+conductive shoes+conductive flooring)? Why not 1×10E8Ohms?
We have tried many waxes and all of them either give an overall reading for the system that is barely, when it is, within the limits above (IEC 61340-5-1 Table 1 – Note 2.

A: That reading is for ANSI/ESD STM97.1-2006 Floor Materials and Footwear- Resistance Measurement in Combination with a person.

So make sure you’re measuring a clean spot on the floor, someone wearing good clean heel grounders, sole grounders, or static dissipative shoes with one probe from a megger in the palm of their hand to earth or machine ground and the voltage on the meter set for 100 volts, as the resistance is greater than 1.0E6 ohms. Now if they fail this test and are less than 1.0E9 ohms, then they pass if they generate less than 100 volts as per ANSI/ESD STM97.2-2006 Floor Materials and Footwear- Voltage Measurement in Combination with a person.

Sorry so long for the response time.

Q2: Many thanks for you help.
What you are actually saying, if I understand it correctly, is that “if the combined resistance of an operator wearing whatever shoes over a a conductive flooring is greater than 1 x 3,5E7Ohms he will generate more than 100 Volts” and
currently in many electronic plants static generation above 100 Volts is not tolerated.

A2: No, that’s not what I’m saying.  I’m saying, as per ANSI/ESD S20.20-2007, that if you fail the < 3.5E7 ohms test, you may pass the less than 100 volts test and still be compliant to 20.20
 
Look on table 2 of page 4 of 20.20 and you’ll see what I mean.
 
Let me know if that helps.

 

ADD: I guess what needs to be understood with 20.20-2007 is that the < 100 volts and the < 1.0E9 Ohms still stands as well.  But if you’re testing per 97.1 and you get >3.5E7 ohms, then you can still pass 20.20-2007 if you have < 1.0E9 ohms per 97.1 AND < 100 volts per 97.2.

If you go to the table 2 chart on page 4 of 20.20-2007, it makes more sense.

26 Feb

Can ESD Wax be applied to bring back dissipative properties?

Q: Into our manufacturing area we have a dissipative floor installed, some areas has lost the dissipative properties, we are using ESD wax to correct those areas.

We are not having good results, we measure point to point and point to ground and these areas still measure insulative, my question is:
The ESD wax only works in floors with dissipative properties, or could it be applied on areas where the floor has lost the dissipation properties?”

A: Thanks for contacting us.  This is one of those questions that I like to pounce on, because it brings up many current misconceptions in the ESD flooring industry.  I’m going to answer your question about using chemicals to perhaps patch up certain areas in your flooring system, but I’m going to reach beyond that question and give a comparison of the ESD flooring system vs an otherwise non-ESD flooring system with an ESD sealer applied to it.  We supply both options here, by the way.  I hope you find what you need here and that this response helps guide you in your application.
Read More

26 Jan

What is the importance of using ESD Footwear on ESD Floor?

Q. What is the importance of having the personnel within an EPA to wear ESD footwear on an ESD Flooring system?

A. Thanks for the inquiry. It was good speaking with you earlier. You had stated that you had concerns about the grounding of your flooring system and my first question to you was about the use of ESD footwear. I believe that you had stated that not everyone was using esd footwear.

You pose a situation here that needs to be addressed as a top priority at all levels of ESD Awareness for every client that we come into contact with. I don’t mean to over-simplify this but I am seeing a common trend in the ESD industry; your ESD system is only as strong as the weakest link in the chain. Another way to say this is; If you buy a Plasma TV, it needs to come with a power cord and you need to plug that in. Read More

05 Dec

The difference between Low Static and Static Dissipative

Q: What is the difference between Low static 3.5kv carpeting and static dissipative carpeting? When used on walls is 3.5kv carpeting ok in electronic equipment rooms?

A: When people refer to 3.5 kV carpeting I believe they are referring to the threshold voltage that people can feel as a nuisance static shock. We deal primarily with manufacture, test, assembly, and application environments where the end-user is protecting expensive electronic components, explosives, assemblies, etc. and the threshold for their needs is down to 100 volts and less.

I believe the 3.5 kV carpeting is considered to be somewhat antistatic (resists or has reduced tribocharging abilities) and is treated topically with some temporary chemical. These types of carpet do not satisfy our needs to provide long-term solutions for the commercial, industrial, and even consumer electronics industry.

I’d like to find out more about what you’re using the carpet for. Are you using it on the walls to deaden noise or create some special environment for audio design? If you need some kind of ESD protection, can you find out what your voltage threshold is- or what is the highest acceptable voltage that your environment can tolerate?

We offer ESD carpet in broadloom form and in tile form in both static conductive (typically around 2.5e04 or 25,000 ohms to 1e06 or 1 Meg Ohm) and static dissipative (1E06 – 1E09 ohm). As the resistance increases, the generated charge dissipates less rapidly to the point that a charge potential exists somewhere in the system and an ESD event occurs. This ESD event may occur without the end user knowing, but it may damage or destroy sensitive devices. Having a textile with a resistance in the static conductive range will discharge this charge potential more rapidly and work to prevent a charge from getting too high in the first place. Different textiles tribocharge at different rates and increase to different potentials, depending which textiles are making contact with and separating from them. Many carpets perform fairly well compared to other textiles in a humid environment. The humid environment may knock the created voltage down from 10’s of thousands of volts to thousands or hundreds of volts, but not low enough to prevent ESD Sensitive Devices from getting damaged or destroyed.

I hope I’ve touched on some of your questions but need to know more about your current application to help you better.

05 Dec

Copper Mesh Grid with two and three layer flooring

Q: Some ESD material suppliers claim that Copper Mesh Grid is not required in case of two layer flooring. Is it correct and if so, why only in case of three layer?

A: This question may be off topic. It sounds like you are talking about ESD flooring, not bench or floor matting. If that’s the case, some manufacturers of esd flooring make a conductive backed tile or sheet good. This backing may be so conductive and along with a conductive esd adhesive, they claim that you don’t have to lay down an expensive copper grid. That’s fine. But if I’m installing the floor, I’ll use copper (or aluminum if requested) tape and run a standard grid the length of the room (along the x-axis) and cross it up (y-axis) so as to ground the floor at least once every 2500 square feet or a couple of times per room minimum. I’ve found that this helps prevent hot spots from tile to tile or gives more consistent RTT (Resistance Top-to-Top or Point to Point). One roll of copper tape would enable me to ground a room that was 60’ x 40’ without a problem. If I have more tape to use, I’ll use it. A liberal amount of copper tape and ESD adhesive is provided free of charge with the purchase and installation of an ESD floor from Ground Zero Electrostatics, Inc.

Copper mesh grid just doesn’t apply to 2 layer or 3 layer mats. They use ground cords. One per every 10 feet, I believe.