What is ESD and Why Does it Matter?
- Sophie Bill
- Jun 22
- 3 min read
Updated: Jun 23
What is ESD?
ESD stands for Electrostatic Discharge. It is the sudden transfer of electrical charge between two objects with different electrical potentials when they come into contact or are brought close together.
For example, the shock you may feel after walking across a carpet and then touching a metal door handle.
Why is ESD important in electronics?
ESD can be a silent killer of electronic components because the discharge is often too small for humans to notice, yet still large enough to damage sensitive devices. Humans feel shocks above 3000 volts whereas electronic components can be damaged with less than 10 volts.
The rapid discharge of static electricity can damage semiconductor junctions and, in severe cases, generate enough heat to cause permanent component failure. Bare PCBs (PCBs without components fitted) are generally far less susceptible to ESD damage than populated assemblies, so ESD concerns are usually focused on electronic components rather than the board itself.
ESD damage is not always immediate. A component may appear to function normally after an ESD event but suffer hidden damage that reduces its lifespan or causes intermittent failures later in the field.
Types of ESD Damage
Catastrophic failure – component stops working immediately.
Latent failure – component appears to work but has hidden damage that may cause future reliability issues.
What can cause ESD?
ESD can be caused by many different things.
Handling - Static electricity from your body transfers directly into the device.
Friction - Packaging, clothing and sliding against surfaces can all generate a static charge.
Dust - Airborne particles and contamination can contribute to static charge generation and increase the risk of ESD events in poorly controlled environments.
Tools - Everyday tools you might find on your workbench can be responsible for generating static charges. E.g. tape dispensers, plastic rulers, soldering irons, fans, printers.
How can ESD be Prevented?
There are lots of ways to prevent ESD, not all will be relevant for your workplace, you will need to analyse your work areas and choose the appropriate prevention methods.
Handling - When handling ESD-sensitive devices you need to ensure you are grounded. There are various ways you can do this, the most common is by using wrist straps. When transporting it is important to use anti-static racks.
Friction:
Packaging - Anti-static packaging is widely available and can come in most forms e.g. vacuum seal bags, bubble wraps, boxes. You want to avoid the use of high static materials such as paper, foam and cardboard.
Note: As long as the primary packaging is anti-static e.g. The boards are secure in anti-static bags, then they are safe to be packed in non-anti-static packaging. Customer requirements should always be checked first.
Clothing - Anti-static clothing should be mandatory for all staff working on ESD-sensitive devices. Anti-static shoes are also great.
Surfaces - Anti-static matting across workbenches is an easy way to prevent static charge build up when working on product.
Dust - Daily cleaning with the use of air ionisers and air purifiers can all be used to help create dust free environments.
Tools - Tools used within an ESD Protected Area (EPA) should be suitable for use around ESD-sensitive devices and form part of an ESD control programme compliant with IEC/BS EN 61340-5-1.
Training - Regular training for staff ensures knowledge is kept up to date and helps reduce risks.
ESD is an often invisible but significant threat to electronic assemblies. With the right training, equipment and processes, the risk can be greatly reduced, helping to improve product reliability and protect sensitive components throughout manufacturing and transportation.
How we control ESD at Advanced Assembly Solutions
At Advanced Assembly Solutions, we have over 35 years of experience manufacturing electronic assemblies and understand the risks ESD presents to sensitive components.
Upon joining our company employees are given ESD training with refreshers completed annually. All employees and visitors must wear the provided anti-static coats and if applicable anti-static shoes. Before starting any work, we use the ESD wrist strap tester before starting at a ESD-safe workstation.
For our customers, we invest in anti-static bubble wrap, packing film and 3 different types of anti-static bags. If needed, we can also ship in anti-static boxes although we highly encourage our customers to allow us to recycle and reuse our packaging.
