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ESD
 | The Abeba Electrostatic Discharge range is very colourful pleasing to look at for a change, they come in lace up trainer styles then the European style with velcro straps then the boots. They all come with two different insoles so you can change to maximise your comfort, Ideal for use in Medical and Surgical Area's of hospitals, car industry, electronics industry, cleanrooms and gerneral use if you want.
Our Swedish clog is EPA for that extra protection from static.
ESD = Elektro Static Discharge
Anyone handling static sensitive devices needs to ensure they take every precaution to protect these devices from the effects of Electro Static Discharge. This applies at every stage throughout the entire production process and it is important that if footwear is being used as part of these precautions that it meets the proper standards with regards to ESD protection.
ESD shoes have much tighter criteria than general anti-static shoes and it should be noted that not all anti-static shoes will provide the proper level of protection required from a full ESD shoe. All Abeba ESD shoes offer this full protection.
What is ESD?
ESD (= electrostatic discharge) is caused by an imbalance of potential on charged objects or people by contact or close proximity. The discharge often lasts only a split second, frequently in form of a spark.
In many cases electro static discharge causes “latent damages” that manifest as defects or trouble only after a certain period or under specific circumstances.
Everybody knows the most popular ESD effects, e.g. discharges when touching a door knob or the crackling noise or even the sparking when taking off synthetic clothes. During the production of electronic or electromagnetic devices (microchips, metal blanks, magtapes, etc.) even the smallest electrostatic discharge can cause invisible damage.
The ESD effect
The triboelectric charge effect is the process during which the charge is generated by the contact and the following separation of two surfaces, while the surfaces can be hard, fluid or gaseous (with particles). It requires approximately 3000 Volts for the human body to sense by touch.
- 100 Volt to delete information from a magnetic data carrier
- 50 Volt to generate sparks which can ignite explosive gases
- 30 Volt to damage electrical components
- 5 Volt to damage highly sensitive hard-disc reading heads during their production
Because of this awareness the following questions should be answered when equipping an electro static discharge protective area (EPA):
- Which voltage can the device tolerate?
- How sensitive is the device to be produced?
The ESD shoe
Shoes are classed as ESD shoes when their on-state resistance value is between 1.0 x 105 Ohms and 3.5 x 107 Ohms or between 0.1 and 35 MOhm according to DIN EN 61340. ESD shoes should be used when the electronic charge has to be reduced by diverting its build-up.
The electrical resistance of ESD shoes lies in the lower area of antistatic shoes for the general professional use.
Electrical resistance
The ESD influencing factors
Shoes used for primary grounding in ESD protection have to be selected in combination with the floor covering to be used. The combination of different groundings and different sole materials is important for the discharge. Further influencing factors in the triboelectric charge are clothes (trousers, shirts, underwear, socks etc), the way of touching, the speed of movement, the grade of contamination and the humidity in the environment.
Generally there has to be a new test after every change of the shoe or everytime the EPA is entered, if the shoe is used for primary grounding. Improper insoles for example will alter the electrical resistance of the shoe and this will in turn affect the performance of the shoe with regards to the required standard.
It is recommended to users of ESD products to make on-site tests of the electrical resistance at regular intervalls and to adhere to correct marking.
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