25 May

What Are the Standards for Electrostatic Protection?

Standards for Electrostatic Protection

So, you’ve just been tasked with building or designing your first Electrostatic Protection Area (EPA). You’ve started doing your research, but there are so many choices, from so many different companies. Suppliers, manufacturers, third party providers… If only there was some established standard for judging the efficacy and reliability of all those pieces and parts.

Well, you’re in luck! In 2007, the American National Standards Institute (ANSI) in cooperation with ElectroStatic Discharge Association (ESDA) released a unified set of standards for the design, implementation and maintenance of ElectroStatic Discharge control programs.

In the midst of World War I, five engineering organizations recognized the need to develop standards that could eliminate confusion and could be adhered to across all disciplines, without regard to politics, profits or personal preferences. These groups reached out to the U.S. Departments of War, Navy, and Commerce to form an impartial third party non-profit organization, then known as the American Engineering Standards Committee.

Following the war, the organization spent the next 20 years establishing several safety protocols still observed today, like eye protection, hard hat standards and in-house electrical safety while at the same time reaching out to other similarly tasked international organizations.

When the United States entered World War II, the organization, which would eventually come to be known as ANSI, helped to accelerate the war effort and productivity, created more effective quality control measures, as well as helping to advance photography, radio, and even the development of Velcro.

In 1970’s, ANSI established a public review process and began the herculean effort of moving the United States to the metric system. While the general public never really connected with the metric system, the effort did bring ANSI to the forefront of private sector companies who discovered standardization was a way to stay more competitive in an increasingly global economy.

With the advancement of personal computers in the late 70’s and early 80’s, engineers at several companies recognized a need for more understanding of electrostatic discharge and its prevention. They formed the ESD Association, a non-profit, voluntary professional organization that for almost 35 years has sponsored educational programs and developed standards to help eliminate losses due to electrostatic discharges.

Together, leaning on the historical experience of both military and several commercial organizations, ANSI and ESDA developed the definitive standard for ESD protection, the very cleverly named ANSI/ESD S20.20-2007.

Covering about every conceivable area of ElectroStatic Discharge, the ANSI/ESD S20.20-2007 utilizes both the human body model and the machine model to provide a broad set of guidelines for ESD protection.

The Human Body Model is the military standard that defines and rates the vulnerability of an electronic device to the ESD generated by a human being touching it. The Machine Model works similarly, except it rates the vulnerability of a device receiving a machine discharge into ground. It was originally developed by car manufacturers as their plants moved to more mechanized production technology.  The Human Body Model is about 10 times more sensitive than the Machine Model.

There is a lot to explore in the ANSI/ESD S20.20-2007 guidelines, but for the purpose of this primer, the document highlights 3 fundamental ESD control principles:

  1. All conductors should be grounded. This includes the personnel and the surfaces they are working on.  We recommend, at a minimum, personal grounding wrist straps, ESD table or bench mats, and a common ground cord.
  2. Necessary non-conductors – certain circuit board materials, device packaging, etc. – cannot lose their electrostatic charge by being grounded and appropriate precautions must be implemented.
  3. Static protective materials, such as ESD shielding bags or ESD totes and boxes must be utilized when transporting sensitive electronics outside a properly prepared EPA.

There are slightly less stringent standards that apply to floors and bench mats, but ANSI/ESD S20.20-2007 is the highest and most comprehensive guideline so far. So when you’re shopping for the parts needed to establish your EPA area, always look for companies that maintain that standard in their products and services.

We would love to be your full service, seamless ESD solution provider; contact us today for more information.

18 May

Conductive vs. Dissipative Materials

Conductivee Vs Dissipative

In the mid-1820’s, Georg Ohm, a self-taught mathematician and physicist, began doing experiments in the newly discovered field of electromagnetism. Hoping to advance his stalled career, he used the work of Hans Christian Ørsted as a jumping off point, discovering an inverse mathematical relationship between current and resistance.

Georg Simon Ohm

Georg Simon Ohm

Unfortunately, in an effort to make his theories more understandable to non-mathematicians, he managed to alienate the scientific community and his groundbreaking work went unrecognized for almost 15 years.

Today, he’s remembered by the law that bears his name and its legacy, the standardized unit by which we measure electrical resistance – the Ohm (Ω).

Electrical Resistance: The Water in Pipe Analogy

To put it simply, what Ohm had discovered, but failed to adequately communicate, is that electricity acts like water in a pipe. In this analogy, resistance tells us how wide or narrow the “pipe” transmitting the electricity is.

When two items touch each other, they create an electrostatic charge – one item is positively charged, and one negatively charged. When the items are separated, it creates a triboelectric effect – a buildup of potential energy which can result in an electrostatic discharge (ESD).

In our quest to prevent ESD, which can be damaging and potentially catastrophic to sensitive electronics and circuitry, there are several approaches that vary, depending on the situation.

To illustrate those, we go back to Ohm’s electrical “pipe.”

At the narrowest end of the pipe, we have insulative materials – wood, carpeting, plexiglass. Insulative materials prevent or severely limit the flow of electrons across their surface.

While it may seem that this is the highest and best protection, the opposite is actually true. Because insulative materials are self-contained, they do not ground – meaning the potential energy continues to build up without going anywhere, until it comes into contact with another object, at which point, the new item is bombarded with the electrostatic discharge.

At the widest end of the pipe, we find the conductive materials – copper, steel, water. Conductive materials offer almost no resistance to electrostatic discharge. The electrical charge moves quickly through the materials – too quickly, which can lead to significant problems, as well as safety hazards.

In between these two extremes are the two materials most often used for ESD storage containers, matting and flooring: static conductive and static dissipative.

Towards the wider end of our metaphorical pipe, we find static conductive materials. Because of the low electrical resistance, electrons flow easily across the surface, and can be grounded safely. Typically, static conductive materials are most often used for ESD flooring.

Towards the narrower end of the pipe we find static dissipative materials. The higher resistance of these materials keeps the electrical charge more under control as it slowly flows over the surface and into a ground. Static dissipative materials are much more commonly used for ESD prevention and can be found in table top mats, ESD shoes and some flooring.

For storage containers – boxes, bins & totes – both conductive and dissipative materials can be used, depending on individual needs. Just keep in mind that dissipative materials have a higher resistance than conductive materials.

For more information, or an even more technical discussion of the properties of ESD materials, contact us today.  We would love to be your full service, seamless ESD solution provider.

11 May

10 Common Terms in ESD & What They Mean

10 Common ESD Terms

In 1865, Lewis Carrol published Alice’s Adventures in Wonderland, at the time, a thinly veiled political commentary wrapped in a fictional form.

Who knew that 150 years later, the book would have spawned several movies, pop cultural references, and a Grace Slick song.

But the most enduring artifact of the novel in today’s world – possibly reinforced by its own self-reference in the Matrix films, is the term “Rabbit hole.” In Alice’s universe, it meant falling into a world of confusion. Today it means losing track of time as you plumb the depths of a topic.

In our effort to be a provider of full service ESD solutions, we give you… The ESD rabbit hole – 10 Common Terms in ESD and What They Mean…

10 Common ESD Terms

The obvious place to start is with the term itself: ESD

ESD stands for ElectroStatic Discharge, a specific type of Electrical Overstress (EOS), defined as the sudden flow of electricity between two electrically charged objects caused by an electrical short, insulation failure, or simple contact. This is most often observed as static electric shock.

Electrical Overstress (EOS) is the exposure of an item to a current or voltage beyond what it can handle. When we’re talking ESD, it’s not just a static shock – because of the nature of sensitive electronics, even just a tiny bit of energy generated by lifting your hand or sliding across a desk can be dangerous enough to damage a component while you’re working, which is shy we recommend common grounding.

Common Grounding is a grounded device where two or more conductors are bonded, or a system for connecting two or more grounding conductors to the same electrical potential. Think of it as a lightning rod for your workstation.

Triboelectric Charging is the generation of electrostatic charges when two materials make contact, or often are rubbed together, then separated. This is what most people call static cling. The polarity and strength of the charges produced differ according to the properties of the materials.

Surface Resistance is measured in Ohms, and tells you how easily an electrical charge can travel across a type of surface. It might be helpful to think in terms of a water pipe analogy. The higher the resistance, the narrower the pipe. In the ESD world, a surface is either conductive or dissipative.

Conductive – A surface is conductive when it has a low resistance, anywhere from no resistance at all, such as water or copper, to mid-level resistance. This would be the wider of the two water pipes.

Static Dissipative – A surface is dissipative when it has a higher resistance, anywhere from the top end of the conductive to so much resistance that only a tiny trickle of “water” comes through the pipe.

Degradation is static electricity damage that weakens an electronic device, while giving the appearance of operating within normal parameters. However, once degraded, a device may fail catastrophically at a later point or just not last as long as it should.

Catastrophic failure is static electricity damage to a device that causes it to cease to function. The device must be replaced.

Ionization is the process by which a neutral atom or molecule acquires either a positive or a negative charge.

To Neutralize is to eliminate an electrostatic field by recombining positive and negative charges, either by conducting the charge to ground or by introducing an equal opposite charge. The charges cancel each other out, leaving a zero charge on the item.

We would love to be your full service, seamless ESD solution provider. For a deeper explanation of any of these terms and how they affect your workplace,  contact us today for more information.

04 May

Finding ESD Storage Solutions

Finding ESD Storage Solutions

There’s a classic scene that appears, with some variation, in every James Bond film.  Bond gets assigned a new mission and he goes to see MI-6’s Quartermaster, or “Q.” Q gives Bond everything he needs to complete the mission, including a few items that seem unusual or out of place.

Of course, as Bond fans know, these elements will at some point be combined to facilitate a distraction so Bond can escape. And usually that distraction is a rather large explosion.

One wonders how he was transporting the items before so that they didn’t explode in his Armani suit.

Of course, in real life, when items combine, the result isn’t usually an explosion.  Or is it?

As we’ve mentioned before, the amount of Electrostatic Discharge (ESD) required to cause significant damage to sensitive electronics is far below the threshold where a human being can feel it.

By the time our bodies create a static charge that we can feel, it’s somewhere between 3 & 17 times stronger than what most electronics can handle without suffering damage.

Even just the controlled blowing of air, like the old canned air computer dust removal techniques can cause static ESD build-up that can be transferred to your sensitive electronics.  And that tiny electrostatic discharge can cause latent or catastrophic failure, costing you time and money.

We’ve discussed selecting the proper shielding bags in a previous post. Another important weapon in your Electrostatic Discharge defense arsenal is anti-static ESD storage containers.

ESD Storage Containers

ESD storage containers are typically made of a conductive material, such as polypropylene or high density polyethylene and provide an added layer of protection, shielding your work areas and personnel from the harmful effects of ESD.

The conductive material provides a barrier which these fields cannot penetrate and prevents the build-up of electrostatic charge. The bins, totes and miscellaneous storage containers come in both static dissipative and conductive. Both control a potential electrostatic discharge, one by resisting it, the other by neutralizing it.

Additionally, be on the lookout for non-ESD protected items that may stray into the Electrostatic Protected Area – transparent tape, plastic sandwich bags, water bottles, Styrofoam coffee cups, even just pieces of paper – can be the source of an uncontrolled electrostatic discharge.

Of course, all of these storage solutions should be used within the minimum guidelines of an Electrostatic Protection Area, that is, wrist straps, ESD mats and a common ground.

We would love to be your full service, seamless ESD solution provider; contact us today for more information.

27 Apr

Why Moisture is the #1 Enemy to Your ESD Flooring

#1 Enemy of ESD Flooring

It’s hard to walk down a sidewalk these days without seeing a crack in the pavement. Some of these have obvious reasons, like strong tree roots pushing them up, while others seem to appear out of nowhere.

When concrete is initially poured on a flat surface, to create a floor or sidewalk, it is left for a day or more, depending on the location, to cure. Curing is the process by which the concrete is protected from evaporation until it hardens.

The wetter and cooler concrete is while it’s curing, the stronger and less permeable it is.

I know what you’re thinking… Wait. Why does this matter to ESD flooring? The short answer is more than you know.

A Concrete Problem

Because of the unique nature of the concrete curing, moisture is captured within the concrete. Again, this helps the concrete stay stronger and last longer. But it has an unfortunate side effect.

You see, concrete cracks when the moisture inside it evaporates faster than it can draw replacement moisture from the ground under it.

You may have noticed that a bare concrete floor is unusually cooler than its surroundings.  There’s even the old wives tale about walking on bare concrete causing arthritis flare-ups.

But concrete doesn’t just capture moisture during curing. After hardening, it also transmits the moisture and the temperature of the ground below it.

All of this leads to the number one reason electrostatic discharge (ESD) preventative flooring fails: moisture permeation.

Flooring Failure

When too much moisture moves through the concrete, it results in a high alkalinity in the concrete.  The higher pH levels react to the bonding agent, causing the adhesive in many instances to fail. And if that failure isn’t discovered, could even lead to mold between the concrete and the flooring.

A properly constructed system built recently should include a vapor barrier – a plastic shield that lessens the moisture transference of the concrete flooring. But older buildings may not include this and preventative measures should be taken.

The best and most economical solution is to install resilient flooring to the concrete base before laying down the adhesive backed ESD flooring. Resilient flooring is an organic floor surfacing material in sheet or tile form: rubbervinyl, cork, or linoleum are all viable options.

You can also apply a resin-based moisture barrier coating before laying down your ESD flooring tiles.

A more efficient method is to simply pour a static conductive water-based epoxy floor covering. This eliminates the need for an additional layer of ESD flooring as the epoxy itself provides the protection.

What you can’t do is nothing. Moisture-related floor covering failures are responsible for over $1 billion annually in damages.

Contact us today for more information; we would love to be your full service, seamless ESD solution provider.

20 Apr

How Do You Care for Your ESD Floor?

How to Care for Your ESD Floors

So you’ve finally got your brand spanking new Electrostatic Discharge (ESD) preventative flooring installed. It looks great, it works great. But how do you keep it that way?

You’re smart enough to know that just like this is a specialized floor, it requires specialized care. Not just any cleaning products will work. You certainly don’t want to void the warranty, or even worse, compromise the ESD properties of the floor. That could drastically escalate costs – replacement of the damaged electronics, replacing the floor itself – having to apologize to your clients and replace the electronics they trusted you to provide.

You can’t find anything in the installation instructions. You hear the boss’ voice around the corner, you know he’s going to ask these questions. You don’t have the answers. You look down and you’re not wearing any pants!

Well, we can’t do anything about your pants, but we do have some answers to avoid that other nightmarish scenario.

For starters, take a break – for the first 5 days following a new installation, don’t wash or machine scrub the floor. This allows the adhesive to properly bond with the concrete base, as well as to prevent excess moisture – the #1 enemy of ESD flooring – to interfere with the adhesive.

The First Steps

Once the first week has passed, do an initial maintenance cleanup. Sweep or dust mop the surface to clear it of all sand, grit, debris, or dirt. Then mix a neutral pH detergent with a small bit of water in a mop bucket.

Dip the mop in the solution and fully wring it out. It is important to ONLY use a damp mop. Do not flood the floor with cleaning solution. Use as little liquid as possible to clean the surface.

If needed, scrub the floor using a rotary scrubber with scrubbing pad or automatic scrubber with scrubbing pads. Again, using as little water as possible!

Use the wrung out mop or a wet vac to wipe up any excess cleaning solution. Carefully rinse the surface with cool, clear water, but not too much, and again vacuum or damp mop up the water and let it dry.

Never use standard floor wax or standard floor finish!  Doing so will destroy the floor’s ability to prevent ESD. A high gloss appearance can be achieved with a high speed buffing machine with an untreated polishing pad.

Daily Care & Cleaning – Two Options

For your day to day cleaning and upkeep, there are two standard approaches for ESD flooring. Both are viable, but for obvious reasons, we prefer the first method.

Safety First!

Always be aware that a wet floor is more slippery, and therefore more dangerous to personnel. Try to coordinate cleaning of the floor to the end of the workday when fewer people are around, put up appropriate signs, and always exercise caution to prevent workplace injuries.

The first step in either case is to sweep or dust/dry mop the surface.

Dry Maintenance Method (Option 1)

By limiting the amount of liquid your floor is exposed to, you stand they best chance of avoiding the #1 enemy of ESD flooring – moisture. The Dry Maintenance Method is a simple, single step process.

Spray clean or burnish floor using a 1200 – 1500 rpm rotary buffing machine with appropriate pads (usually white) and a spray buff solution containing water, alcohol and a pH neutral detergent.

If heavy cleaning is necessary use a more concentrated pH neutral detergent and a brown pad.

Wet Maintenance Method (Option 2)

Similar to our initial cleanup procedures following installation, the wet maintenance method uses a damp mop and a cleaning solution that includes a neutral pH detergent.

If the floor is exposed to grease or oil, a pH neutral, citrus-based degreasing detergent may be used.

Scrub with rotary scrubber with scrubbing pad or automatic scrubber with scrubbing pads. Again, do not flood the floor with solution, water or any liquid.

Wipe up the solution with a damp mop or wet vac.

Carefully rinse with clean cool water, wipe it up, then let the floor dry (generally overnight).

Two final notes:

Several times we’ve mentioned using a pH neutral detergent. While there are many options, we highly recommend the industry standard – ZeroStat products. They can be purchased through our site or any reputable supplier of ESD preventative products.

Earlier, we recommended not using a standard floor wax. While there are professional ESD waxes available from ZeroStat that maintain the ESD preventative properties of your flooring, even those waxes generally cut five to ten tears off the life of your ESD floor and should be used with caution.

We would love to be your full service, seamless ESD solution provider.  Contact us today for more information.

12 Apr

What Are ESD Mats & How Do They Work?

Static Electricity and ESD Matting

Have you ever been working in your garage and accidentally made contact with a metal part of an ungrounded electrical appliance, like a box fan or a badly wired junction box? The jolt you receive wakes you up faster than a cup of coffee or one of those 5-hour energy drinks. Now imagine what that could do to sensitive electronics—devices and circuit boards with a much lower resistance than your skin.

Considering just the physical activity of moving your arms and legs can build up relatively large electrostatic discharges (ESD) that we may never notice, there’s very little activity that isn’t dangerous to electronic components – even their assembly. But there are steps you can take and tools that have been developed to protect your sensitive electronics. One simple, popular tool is an antistatic or ESD mat.

How Does an ESD Mat Work?

Antistatic or ESD Mats have a high electrical resistance, which allows the electrostatic discharge to “flow” across the surface of the mat at a slow rate – enough to get the ESD away from your electronics, while at the same time neutralizing what little charge inevitably does build up.

The simplest form of an ESD mat is simply that – a tabletop mat, about the size of a placemat, that you use on a desk, table or any flat surface. They typically connect with a personal grounding wrist strap – adding additional protection by drawing any ESD charge away from the person working on the device.

ESD mats also use a common ground to draw the electrostatic discharge away from offending areas. Without that ground, the mat could, in theory, protect the item being worked on at first, but would then transfer the ESD to the very next thing it comes into contact with – the next item, the person holding it (and then to the item), or even right back onto the item it was originally meant to protect.

For larger workspaces, or dedicated ESD workstations, you can invest in rolls of ESD matting or custom-sized mats. You can even get ESD matting with built-in static control monitors and self-adhesive backing.  Just make sure, regardless of the size or quantity used, that all of the mats are grounded.

You can also increase protection as well as worker safety by investing in ESD flooring mats, which not only act as further neutralization of potential electrostatic discharge but also can provide cushioning, easing the fatigue of the person standing while working on the electronic devices. The hazard of slippery floors is also alleviated by an ESD flooring mat.

Bear in mind that not all ESD matting is tested to the same level.  We recommend checking to make sure the mats you are buying are properly assessed to ensure you are getting the protection you need, and ideally, include ISO certification for your company’s protection.

We would love to be your full service, seamless ESD solution provider.  Contact us today for more information.

05 Apr

The Truth About 11 Myths of Electrostatic Discharge: Part 2

11 Myths of Electrostatic Discharge

Last week we shared with you Part 1 of The Truth About 11 Myths of Electrostatic Discharge; here’s Part 2…

Myth #6 – An ESD bag is all the protection I need.

There is a somewhat popular belief that you can use the ESD shielding bag that your circuit board or sensitive electronics was shipped in as adequate “matting” when you are working. This could not be more false.

Regardless of which ESD shielding bag you receive or purchase, it ONLY provides ESD protection while the item in entirely enclosed inside a sealed bag. Outside of the bag, it can actually increase the chances that you will generate an ESD event, because the bag is designed to “push” a charge away from the contents of the bag – right into your electronics.

Myth #7 – Grounded metal offers a safe haven from ESD.

In fact, conductive materials – like metals – are not safe surfaces for sensitive electronic components that could be subject to an electrostatic charge, even if they are grounded. In fact, the charge dissipation is so fast, the resistance to ground has almost zero impact.

The point of grounding is to get everything at the same potential energy level so that current from an ESD can’t flow where it shouldn’t.  Using metal, even grounded metal, voids this effort.

The next three myths are similar in nature…

Myth #8 – Circuit boards without complementary metal oxide semi-conductor (CMOS) are safe.

On its face, this seems obvious, as it is hard to find a circuit board without some CMOS components. However, ALL circuit boards are susceptible to electrostatic discharges and the damage they can cause.

Myth #9 – A printed wiring board (PWB) permanently protects a circuit board.

Just because a component is inserted into a PWB, that does not protect it from potential ESD damage. It does decrease the likelihood that fatal loss will occur, as the voltage the entire board can sustain is increased.

But this is by no means a guarantee of safety. All proper precautions must be taken when handling sensitive electronics.

Myth #10 – Once products are mounted on circuit boards, ESD mishaps cannot occur.

This is similar to the above myth.  But unlike PWB boards, unprinted boards can actually leave sensitive components even more vulnerable because there is less resistance to slow the electrostatic discharge down.

 Myth #11 – Small companies cannot afford proper ESD protection.

On the contrary, small companies cannot afford not to have suitable ESD protocols and tools. The risk of damage and the costs associated with it are just too excessive not to invest in the proper implementation of an ESD protected workstation – even a portable one, if need be.

We recommend at a minimum, personal grounding wrist straps, dissipative ESD matting and grounding cables.

We would love to be your full service, seamless ESD solution provider, no matter what your size or budget.  Contact us today for more information.

29 Mar

The Truth About 11 Myths of Electrostatic Discharge

11 Myths of Electrostatic Discharge

Would it surprise you to know that a good portion of our modern world would be unable to function without the help of electrostatic discharges (ESD’s)?

No one seems to know quite how it happened, but in 1984, Scott M. Kunen applied for a patent for a “touch controlled switch” – a device he had developed to allow lamps to be turned on or off with the touch of a human hand.

Little did he know that less than a decade later, computer companies would begin adapting his technology, covering it with a variety of static controlling sheaths, creating the capacitive-touch screen, the basis for all modern smart phones, tablets and touch screen laptops.

So, here’s the truth about the myths of electrostatic discharge.

Myths About Electrostatic Discharge

Myth #1 – All ESD is bad.

The truth is, most people use ESD everyday to make phone calls, send text messages, and create emails. The touch controlled switch and the capacitive-touch screen both operate by transmitting small ESD charges from your body into the devices to signal turning a light on, or the letters or numbers desired.

Myth #2 – Electrostatic Discharge is a modern day problem.

Believe it or not, ESD and necessary precautions to prevent it are older than the United States. In the 1400’s, forts and places that stored or produced explosives, gun powder, and even sawdust could fall prey to horrible accidents, so early forms of ESD control were developed and implemented.

Except, of course, when the good guys needed to blow up the bad guys’ stash in a Hollywood movie.

Myth #3 – ESD problems are really quite rare.

In truth, because of the extremely low levels of ESD required to damage small electronics and the fact that damage isn’t always visible or catastrophic, we may never know just how prevalent ESD events are.

Visible static sparks generated by our bodies have to build up between 500-1000 volts, and it takes twice that charge to be felt.  Most sensitive electronics can be damaged by 100 volts or less.

And even if the device continues to function as expected, its life expectancy may be severely diminished and in some cases, latent failure can occur, causing even more damage.

Since we cannot fully prevent or even detect an ESD event, all precautions should be taken to avoid an accidental discharge.

Myth #4 – Discharging fingers and tools before using them is sufficient precaution against ESD mishaps.

Unless you are able to hold your body AND tool perfectly still, you can (and often do) build up a replacement charge that can be discharged into your electronics.

As mentioned above, because of the negligible amount of charge necessary to potentially damage the sensitive parts, you have no way of knowing you are not transmitting a dangerous ESD. It’s better to be safe than sorry.

We recommend that you always use personal wrist straps, dissipative mats and grounding cords for the best chance of circumventing ESD problems.

Myth #5 – You have to touch an item to transmit an ESD to it.

As mentioned above, it takes very little for the human body to build up an electrostatic discharge. Just the movement of lifting your foot off the ground can generate up to 1,500 volts.

And that generated charge can easily leap from your hand to your unprotected device inches away.

Stay tuned next week for Part 2 of The Truth About 11 Myths of Electrostatic Discharge…

We would love to be your full service, seamless ESD solution provider, no matter what your size or budget.  Contact us today for more information.

03 Mar

Selecting the Proper Shielding Bags

Choosing the Right Shielding Bag

In Michio Kaku’s book, Physics of the Future, he notes that today’s smart phones have more computing power than NASA had in the 60’s when they were plotting and launching the moon landings.

The latest SONY Playstation can outperform the supercomputers the US Government used in 1997 – 14 years after the movie WarGames.

In 1965, Gordon Moore, one of the founders of Intel, observed what became known as “Moore’s law.” He postulated that computers would progressively become more dense while at the same time increasing their processing speed.

This can be both good and bad news for computers. The bad news being that every time a component gets 10% smaller, it gets 10x more sensitive to electrical shocks, even those coming from simple static electricity. Static in your workplace can be dangerous and expensive if you’re not properly prepared.

One important weapon in your arsenal for defense against Electrostatic Discharge (ESD) is shielding bags.  Which bag is best? They all have their pros and cons to consider.

Pink Poly Bags

The earliest defense against ESD was created in the 1960’s.  Dissipative Poly Bags, usually referred to as Pink Poly bags because of their unique color – introduced as an easy way to differentiate their static control abilities from standard plastic bags – are coated with a chemical that resists static.

Unfortunately, Pink Poly bags have no shielding capability. An ESD of any significance will travel through the bag and potentially damage components inside. They are best utilized today to package support or processing materials that do not themselves need shielding.

The antistatic properties of the bags help to protect sensitive components near the bags. This makes them a helpful solution as opposed to normal plastic bags, but you should always have a grounding system in place – mats and personal wrist straps at a minimum.

Black Conductive Poly Bags

Black Poly Bags are obviously a step up from their Pink predecessors. But in this case, their advantages are also their biggest flaw. Like the Pink Poly’s, the Black bags are antistatic, with the added benefit of some conductivity, designed to help protect its contents from ESD’s.

The problem lies in how quickly the bags dissipate the electrical charge. The rapid discharge of the ESD can actually generate a spark between the person or object creating the charge, and because the bags lack an additional insulation layer inside the bag, that charge can easily penetrate it.

Plus, there’s the added complication of the bag’s color. The conductive carbon leaves the bag opaque, requiring the contents to be removed to be seen, leaving the potential for damage.

The biggest benefit of the Black Poly’s was some shielding at a lower price point.  But in recent years, shielding bags have become much more affordable, and reputable vendors have effectively eliminated them from their inventory.

Shielding Bags

Shielding bags combine the antistatic and dissipative qualities of the poly bags with metal shielding and a polyester insulator (or dielectric) layer. Where Pink Poly’s stop about 10% and Black Poly’s 30%, Shielding Bags stop 97% of electrostatic pulses.

Shielding bags are classified in two ways:

Buried Metal (Metal-In)

Buried Metal bags consist of a dissipative poly layer, glued or laminated on top of a metallized polyester – usually aluminum, but sometimes nickel or copper – laid over an additional dielectric polyester layer.

The metal between two layers of plastic offers better protection than the alternative.

Surface Metal (Metal Out)

In Surface Metal bags, the layers are ordered differently, with the poly and the dielectric polyester glued together, then coated with a nickel sprayed with an abrasion resistance coating.

Unfortunately, the outside metal coating causes a faster dissipation of electrical charges, resulting in sparking issues similar to that of the Black Poly Bags, although not as dangerous.

Moisture Barrier Bags

For long term storage or moisture sensitive items, Moisture Barrier bags provide the ultimate protection. These bags are similar to, but stronger than normal shielding bags and provide an additional protection with a moisture vapor barrier.

There are two types of Moisture Barrier bags: Foil and Tyvek (utilizing the DuPont material) or Heavy Metallization.  Both provide similar levels of protection, the difference primarily being the higher cost of the Tyvek structured bags.

Static protective bags should always be implemented as part of a more comprehensive static control environment, which should always include proper grounding tools.  And while expenditures are always a factor, consider the insignificant price of proper protective measures when compared to the cost of replacing the delicate components inside the package.

Contact us today for more information; we would love to be your full service, seamless ESD solution provider.