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Everything You Need to Know About ESD Safety

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You’ve probably heard the term ESD or electrostatic discharge, or at the very least you’re aware of the danger of touching computer parts without touching the metal of your computer case. Gotta touch the case first, right?

Maybe you’re scared to death of it frying your computer parts. Maybe you have no fear of it at all, slinging computer parts around with reckless abandon. Maybe you have no idea what I’m talking about right now.

ESD is a more lethal threat than most professional techs know, doing untold damage that might not show itself for months to come. You won’t see the damage happen and you won’t feel it. ESD truly is the silent killer.

ESD warning symbol The international symbol for ESD sensitive materials.

What is ESD?

Every material you can think of has the potential to carry to an electrical charge.  Clothes, people, coffee cups, even air all have the potential to pick up a charge.  Electrostatic discharge occurs when one of these materials transfers its charge to another material.

A quick bit about the different types of materials in relation to static electricity.  Materials fall into two different categories, conductors and insulators.

Conductors are things like metal and human sweat that can transfer electricity easily. Insulators are materials like styrofoam and many plastics that have a harder time transferring electricity.They will still hold an electric charge if they are imbued with one. Think about rubbing a balloon on your head in order to get you hair to cling to the balloon. Both of these carry risk in terms of ESD, as the problem occurs when an item with a negative charge gets close to an item with a positive charge and they interact causing an electrostatic discharge.

The most common example of an ESD event is when you walk on a carpet then touch a door handle and feel a slight shock. This is actually a fairly large discharge as it takes 3,000 volts for a human to feel the effects. Meanwhile, circuits can be deformed by as low as 10 volts, depending on their ESD safety rating.

You can think of ESD as basically mini-lighting

Is it really a problem?

The Electrostatic Discharge Association says that ESD is the leading cause of failures in integrated circuits in the field. Despite this, I have personally heard dozens of people say some version of “I never worry about it, and it’s never been a problem.”

ESD today is a bit like Germ Theory was 150 years ago. Before Louis Pasteur came along and proved that germs were responsible for the vast majority of illness, everyone thought that tiny invisible creatures that we couldn’t hear or feel causing that much damage was downright ludicrous. They knew about bacteria, they just thought they were harmless.

Similarly, most people interested in tech today are aware of ESD, but many don’t believe that it is much of a threat. Largely, this is because those people never see the damage caused by ESD.  Not just because it happens at a microscopic level, but because the damage may not initially present itself.  It may take days, weeks, months or even years for ESD damage to cause failure in a device. This is commonly called latent damage, as opposed to catastrophic damage which is immediately noticeable. In fact, it is more common for an ESD event to cause erratic or undesired behavior in electronics.

It is estimated that high-tech companies lose between 4-6% of their gross sales to ESD damage, around 5 billion dollars a year. The thing is the majority of that loss does not happen at their facilities. Manufacturers of processors, boards and other chip-based parts have stringent ESD safety in place. The majority of the loss comes from the field where techs performing installation and repair often ignore ESD safety procedure. One company estimated that a 5 dollar part could cost them up to $30,000 to replace because of ESD damage.

Obviously, that’s an extreme example but imagine wasting hundreds of dollars on an SSD upgrade only to find you may have shortened the life of you fancy new drive. The worst part is you wouldn’t know it until it was too late.

Common Causes

Many things can contribute to ESD. One of the more common, yet overlooked, factors is humidity.  Dryer environments allow for a larger buildup of static energy, as moisture in the air often has a negative charge that dissipates built up positive energy in bodies moving through it.

Various materials in a workplace often contribute to ESD. We are surrounded by common insulators, such as synthetic clothing, paper, plastic bottles and even our own bodies.

Many normal work activities create a static charge that builds up in our bodies and clothing, waiting to jump to the first available ground and create microscopic damage to our computers. Some movements such as walking across carpet or removing an item from bubble wrap can create upwards of 35,000 volts. Even normal body motion can create 6,000 volts in a low humidity environment.

How to prevent ESD damage.

The first thing to think about with ESD is eliminating risks associated with electrostatic discharge. That means taking care of insulators and conductors.

Conductors are easily dealt with by making sure they are grounded.  Since electricity easily flows through them, it will take the simplest route and discharge to a grounded source.

Insulators cannot be grounded.  It is best to make sure they are removed from a work area before starting work. Having them even close to electronics can cause them to create a static field that discharges to the circuit.

It’s important to use static shielded bag whenever you are transporting sensitive electronics. Even if it’s just from one desk to another, anytime you are touching circuits and aren’t grounded they should be in static shielding.

antistatic and ESD safe bags An Anti-Static bag on the left and static-shielding bag on the right.

There are two different kinds of static bags to be aware of. Anti-static bags are often translucent pink. These bags are made of a plastic that does not cause static build up, making them safe for electronics. They will not actually protect parts from an exterior electrostatic discharge. Static shielding bags, on the other hand, are usually silver in color, and will almost always have printing identifying them as static shielding. They also prevent static build up, but they also will shield anything inside of them from ESD. They are made of multiple layers of materials that act as mini Faraday cages.

If you live or work in a dry climate it is worthwhile to add some humidity to the air.  You can either use a cheap humidifier, an evaporative cooler, or place a damp rag over a fan (this can have some hazards of its own, so be careful!).

Keeping insulators, like plastic bags, styrofoam cups, and paper, at least 12 inches away from any exposed parts will prevent any accidental ESD events.

After taking these precautions, the only left to do is to ground yourself and your workstation.

How to set up an ESD-safe workstation

ESD-safe grounding wrist strap An ESD-safe wrist strap connected to ground, to dissipate charges that build up on your body.

The most common method is the use of an ESD mat and bracelet. The mat needs to then be hooked up to ground. The most common way is to buy an outlet adapter that is hooked to the mat and then plugged into a three-pronged wall socket. In most modern buildings the third prong will be ground. The mat can also be attached to the center screw on most wall outlets, as this will also be a source leading to ground. The wrist strap is then hooked up to the mat and worn on the wrist. The strap is basically a wire connecting the wearer to a ground source. From here on out all electricity generated from the wearer’s movement will safely discharge through the strap. This is exactly how we handle all circuits here at Beetstech

Having a dedicated workstation with an ESD mat is not always an option, and they can get a bit pricey.  For small personal repairs, it can be sufficient to use just an ESD wrist strap.  In this case, you will still need to hook the strap to a ground source. The best thing is an unpainted piece of metal that is hooked to a ground.  In desktop PC’s this can be part of the power supply. This may be harder to do in laptops. In that case, you’ll need to find something grounded to hook it up to. Again, an outlet adapter is a good choice. You also need to make sure your work area is safe from static build up.

Another choice, that I honestly cannot recommend, is to constantly discharge your static build up.  People often say that touching a metal computer case or another metal appliance like a radiator before you start working is enough to dispel fears of ESD.  This is true in principle but doesn’t necessarily work in function.  Touching a grounded metal source will discharge any static you have, but as you work you will build up more static.  The only way this method could be effective is if you constantly touch the appliance.  Since this would leave you with only one hand, it just isn’t practical. Touching a computer case even every few minutes might not be enough.

I know there are lots of people out there who say this method is more than adequate. But remember, ESD is invisible and its effects can often take months to manifest. While these people may not see any problems, it is possible and even likely that they have done a microscopic amount of damage that can lead to irregular behavior or even failure down the road. Don’t take the risk, properly ground yourself while working on computers.

Hopefully, you’ve learned a little about ESD. Most importantly, I hope you remember to take the necessary precautions next time you work on a computer. Remember, you can’t see or feel when an electrostatic discharge event happens.  You also may or may not know that any damage was done right away. It simply isn’t worth risking hundreds to thousands of dollars when a few minutes and a few dollars could prevent it.

Have something to add or something to ask? Go ahead and let me know in the comments.

About The Author

Brite Cheney

I am an English major at CSU, Chico with a lifelong interest in computers and technology, and joy for writing about all things tech.

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Linda

Do all capacitors and resisters need ESD protection and how do I tell if they are not marked?

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