How do you know an ESD safety shoe really performs?

Beyond ESD certification

ESD safety shoes help control electrostatic discharge in workplaces where sensitive electronic components and equipment need to be protected.

At the JALAS factory in Jokipii, Finland, ESD performance can be tested and verified under carefully controlled conditions in a dedicated ESD laboratory. Completed in spring 2025, the laboratory gives Ejendals greater possibilities to test, understand and verify the ESD performance of JALAS safety shoes.

Sari Pirkkanen is Laboratory Coordinator at Ejendals. She joined Ejendals one year ago and brings extensive experience of testing safety shoes for ESD performance.

“As a user, you know you have an ESD-certified shoe when you see the black-and-yellow ESD symbol. But the symbol doesn't tell you how far within the requirements the shoe actually performs.”

– Sari Pirkkanen

Why is ESD protection important?

Electrostatic charge can build up on a person and be discharged when they come into contact with another object. In ESD-sensitive environments, even a discharge that a person cannot feel can potentially affect sensitive electronic components.

ESD footwear helps provide a conductive path through which electrostatic charge can dissipate in a controlled way, reducing the risk of electrostatic discharge.

This makes ESD protection particularly important in workplaces where sensitive electronics, components or equipment are handled.

How are ESD safety shoes tested?

At the JALAS laboratory, safety shoes can be tested under controlled climate conditions according to SFS EN 61340-4-3.

Before testing, the shoes are conditioned for three days in a climate chamber at:

• 23°C
• 12% relative humidity
• 72 hours

There is a good reason for using such dry conditions. Humidity generally improves conductivity, so conditioning the shoes in very dry conditions makes the test more demanding and provides a clearer picture of how they perform under challenging conditions.

After conditioning, the shoes are tested individually according to the standard. The ESD measurement is performed using a voltage of 100 V.

What do the ESD test results tell us?

The black-and-yellow ESD symbol makes it easy to identify footwear that meets the requirements for ESD footwear. Laboratory results can tell us more by showing the actual measured performance of the shoe.

All JALAS Tempus safety shoe models are ESD certified. Testing has also demonstrated ESD performance with a substantial margin within the applicable requirements.

ESD performance at a glance

• 100 MΩ – ESD upper resistance limit
• 35 MΩ – Ejendals internal limit
• Below 20 MΩ – Typical JALAS Tempus result

Lower resistance indicates a greater ability to dissipate electrostatic charge.

These results provide additional insight into the ESD performance of the footwear beyond simply demonstrating that it meets the required threshold.

What gives JALAS Tempus its ESD performance?

Reliable ESD performance starts with the construction of the safety shoe and the materials used throughout it. In JALAS Tempus, these are carefully controlled during production, and finished shoes also undergo ESD testing at the supplier site.

Having tested many shoes for ESD performance during her career, Sari is particularly confident in the technical construction of Tempus.

“When I look at the construction of Tempus, I can see that the key elements for good ESD performance are there. And then, of course, we have the test results to confirm it.”

– Sari Pirkkanen

What affects ESD performance in everyday use?

Even a high-performing ESD safety shoe does not work in isolation. Footwear, socks, flooring, environmental conditions and the wearer all form part of the ESD system.

Keeping the outsoles reasonably clean is one simple way to help maintain ESD functionality. Dirt and contaminants, such as mud, can interfere with the contact between the footwear and the floor and affect ESD performance.

Ejendals also recommends using certified ESD socks together with ESD footwear and following the ESD procedures established for the workplace.