Which Arm Should Wristbands Be Worn On?

Which wrist you decide to wear your anti static wrist strap on is often a matter of personal preference. 

If you have the grounding point for the wrist strap cord on your left you may find wearing the wrist strap on your left makes the most sense.  That way the cord isn’t dragging across your work. 

However, you may find that it is better for you to move the grounding point to your right and then wear the wrist strap on your right hand.

How Often Should An Anti Static Wrist Strap Be Replaced?

There is no specific rule on a lifespan of a wrist strap. Any company policies should be followed on replacements but a good general rule of thumb is to look at the overall use, possible wear and cleanliness of your individual wrist strap.

Often companies determine a guideline on replacing them annually, semi-annually or quarterly. 

This small change can often feel good for those that use a wrist strap daily and especially those who share a wrist strap at a common workbench or workstation.

It can be a small investment in employee satisfaction to have an upgrade to the tools and equipment on a regular basis.  Replacing a wrist strap can be a small but strong signal from management that the company cares about proper ESD procedures.

Why Use An Anti Static Wristband?

The goal of using ESD wrist straps is to safely provide a way for static electricity to dissipate without causing electrostatic damage. The less ESD events that occur the better. An ESD protected work environment will enhance safety which helps to increase efficiency and production. While ESD wrist straps are highly effective pieces of equipment, it’s always best to support safety initiatives with the addition of ESD mats and other essential supplies. Short-term investments in high-quality ESD gear will pay off in the long-term.

Operators should use an anti static wristband to ensure any static discharge has a way to go from themselves to the ground safely. Without wearing a wristband whilst working on a static sensitive device/component you could effectively transfer static discharge onto the item and cause significant damage. This can be very costly to replace and time-consuming.

By wearing a wrist strap, you are not only taking an important step to prevent ESD from inflicting damage but you are also setting an example to your peers and managers.

How Do ESD Wristbands Work?

ESD wrist straps come in a variety of materials, but the general concept for each is the same; to provide a path for electrostatic ground.

For an ESD control wrist strap to work, it is either connected to earth bonding points fitted into workstations, typically via 10 mm press studs, or come with a removable coiled cord and crocodile clip for mobile applications.

The strap is fastened around your wrist using an adjustable band. The wristband should be worn snug to the skin with its coil cord connected to a common point ground which is connected to ground, preferably equipment ground. Typically, the alligator clip is attached to the computer or sensitive electronic device being worked on.

An anti static strap must be connected to a grounding source like a bonding plug in conjunction with a ground lead in order for them to be effective.

Once an ESD wrist strap has been secured to the wrist and connected to the earth bonding point or sensitive piece of equipment, you are safe to work without fear of ESD occurring. This allows you and your workforce to go about your daily tasks freely and drastically reduces the chances of static electricity building up.

 

How Well Does Relative Humidity Of The Surrounding Atmosphere Control The ESD?

The relative humidity (RH) directly affects the ability of a surface to store surface charges. The higher the RH, the less time an item will hold a charge. The method of surface charge reduction (due to increased RH) can be attributed to recombination and or conduction. As the RH increases, so does the natural conductivity of the air, but even at 100% RH the increase in the natural discharge rate cannot be substituted for proper ESD control practices.

Are Wrist Straps Necessary If All Other ESD Precautions Are Taken?

Wrist straps are not necessary if an operator is wearing two-foot grounders on a conductive grounded floor and doesn’t lift both heels/toes at the same time; like some people do when sitting down. If an operator is also wearing an ESD jacket but is not electrically connecting the jacket to either their body’s skin or ground, then the jacket is providing only partial protection.

Charges on the jacket may have nowhere to go or discharge to if the jacket is not grounded. A popular way to ground the jacket is with a coil cord either attached to a snap on the waist area of the jacket or via a wrist strap snapped to the inside cuff of an ESD jacket.

Click here to view our full range of ESD wrist straps.

What Is Static Electricity?

All items are made from small atoms. These atoms are made up of even smaller items called protons, neutrons and electrons. The protons are charged positive, the neutrons have no charge and the electrons are charged negative. Under normal conditions there are the same amount of protons and electrons giving atoms no charge.

However, these electrons can move. When separating or rubbing together of materials, electrons can move from atom to atom or from one material to another (triboelectric charging). This can mean that atoms can hold a positive or negative charge, (dependent on movement and direction of electrons). If the material in question is an insulator, this charge can be held and not move. This is called static electricity.

The rapid movement or decay of these charges can cause expensive problems, whether it is huge and dangerous charges such as lightening or simply an annoying (and sometimes painful) “electric shock” when touching a filing cabinet or when getting out of a car. (The charges are normally on you!).

These charges can be a huge problem for small sensitive electronic devices. Some devices can be damaged or destroyed by as little as 10 volts. Charges on your body, simply by walking or even sitting at your chair, can be in excess of 5000 volts, (human body model). This can be caused by items of clothing rubbing together or by shoes separating from insulating flooring such as carpets.

Imagine the damage this could cause. This is why it is important that insulators should be avoided and all possible static electricity generators (such as you) should (must) be grounded to eliminate any build up of charges.

How Should I Set Up An ESD Workstation?

Before setting up your ESD workstation, you will firstly need to refer to the most up to date IEC61340-5 standard which will give you all of the information you will need to set up an ESD workstation safely and within the current specification.

What do you need to set up your ESD workstation?

A Work Station.

There are ESD protective workbenches, and selecting one would be the best practice. However, most companies use regular workbench. Materials used can vary, but it is best to use a workbench that is constructed of metal and wood, and not one containing large portions of high charging insulative plastic.

A Working Surface Mat.

Most workstations will use pliable ESD matting to cover the bench and be the ESD work-surface on which to handle ESD sensitive (ESDS) items. The mat needs to be grounded and the best practice is to use metal grounding hardware snaps and ground cords connecting the work-surface mat to the common point ground. The entire bench-top should be covered by the ESD mat. Matting can be conductive or dissipative. Per ANSI/ESD S20.20 the required limit is less than 1 x 10E9 ohms and ANSI/ESD S4.1, the work-surface standard, recommends a low limit of 1 x 10E6 ohms. Per S4.1

A Working Surface Mat Grounding Cord and/or a Floor Mat Grounding Cord.

A basic ESD control rule is to ground all conductors including people at the ESD workstation. Grounding works great and will reliably remove ElectroStatic Charges to ground.

A Common Ground Point – An Earth Bonding Point (EBP) Plug or Bracket.

The first step in ensuring that everything in an EPA (ESD Protected Area) is at the same electrical potential is to ground all conductive components of the work area (work-surfaces, people, equipment, etc.) to the same electrical ground point. This point is called the common point ground. The next step in completing the ground circuit is to connect the common point ground to the equipment ground (third wire, green). Most locate the common point ground at the side edge of the workbench or towards the back of the bench-top.

An ESD Wrist Strap.

Most workers, required for sitting workers, will be grounded via a wrist strap. The wrist strap needs to be selected and there needs to be an adequate number of ground points available. Even if typically the workstation is for only one worker, more than one ground point should be available to ground an additional worker, supervisor, or other ESD control element.

ESD Floor Matting.

It is not required to have ESD flooring, but it could be selected to be low charging and/or a means to ground mobile equipment. Per S20.20, the required limit for Flooring is less than 1 x 10E9 ohms. For a standalone ESD workstation, a floor mat can be used with a ground cord connected to the workstation’s common point ground. We recommend conductive floor matting less than 1 x 10E6 ohms to be able to meet the Flooring/Footwear required limit of less than 3.5 x 10E7 ohms.

Foot Grounders (or ESD Shoes)

Instead of a wrist strap, a standing or mobile worker can be grounded using a Flooring/Footwear System. So ESD shoes or foot grounders can be selected. This means of personnel grounding requires both ESD flooring and ESD footwear. The ESD footwear is to be on both feet. Unless body voltage testing has been completed, the required limit per Compliance Verification ESD TR53 is of less than 3.5 x 10E7 ohms. The best practice is to use sole grounders or full coverage grounders and not heel grounders.

Ionizers

A bench-top ionizer or overhead ionizer can be selected to neutralize ElectroStatic charges at the workstation. This is the only ESD control method available to neutralize ElectroStatic charges on essential insulators or isolated conductors that may be at the workstation. The required limit per S20.20 is less than +/- 50 volts offset voltage (balance). In addition, the Discharge Times should be measured, both the time necessary to reduce +1,000 volts to +100 volts and the time necessary to reduce -1,000 volts to -100 volts.

ESD Bags, ESD Packaging, and ESD Storage.

Packaging and material handling containers at the ESD workstation should be low charging and have resistance (conductive or dissipative) so ElectroStatic charges can be removed to the ground. Shielding bags are also used additionally having the ESD control property of discharge shielding.

A Set-Up Of An ESD Workstation

Can I Install Over An Existing Floor?

In many cases it is possible depending on your current flooring. We recommend a site survey to establish whether this is possible or if your existing floor needs to be removed before the new ESD floor can be laid.

If you would like to discuss this further with our team, please contact us and we’ll get back to you as soon as possible.

What Is The Difference Between ESD and Anti Static Flooring?

If you are looking for a flooring solution for your workplace that controls static charge, you may be wondering what the difference is between ESD and anti static flooring and which one to purchase. Ultimately, each type of flooring prevents a person from building up a charge as they walk across the floor so they do not get a shock when they touch something that conducts electricity. However, the top layer of an anti-static floor has a coating that dissipates static across its surface so you never build up enough charge to get a shock, whereas ESD is a much more robust solution because it is actually earthed. ESD flooring gives a much higher level of protection than anti-static matting. This is because it is actually grounded.

The term anti-static refers to a very specific electrical resistance range of between 10⁹ and 10 to the 11 and only means that the floor itself will not generate static. It does not mean that the floor will eliminate static build up or dissipate static that may have already been built up in the body. This can only be achieved with a conductive (resistance range of between 10⁴ x 10⁶) or a dissipative (10⁷ to 10⁹) floor covering.

In general, you will need an ESD floor if you are manufacturing, repairing, servicing, handling or using equipment that is susceptible to damage from electro-static discharge, typical sectors would include the manufacture of components for the electronics industry, aviation, automotive, IT, medical, oil and gas, telecoms and IT for example. For electronics manufacturing applications that require the use of ESD footwear it’s fine to use charge-generating flooring materials like conductive vinyl.

Click here to view our full range of ESD Flooring.