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PEZZOL is proven as a partner in electronically sensitive fields of work.
For people who work in the microelectronic field or with high-frequency technology, apart from absolute cleanliness at the workplace, above all the protection of product and working material against electrostatic influences counts. This is especially true in semiconductor technology, the automotive industry, in physical research laboratories or in electromedicine. That is why experienced technicians and engineers in particular rely on the ESD PEZZOL safety shoes.
ESD = Electro Static Discharge
The ESD PEZZOL safety shoes actively ensure a permanent, gentle discharge of the wearer (warning: the ESD range does not have an insulating effect!). - A quality feature that is clearly visible from the outside on PEZZOL ESD shoes through the circular, yellow ESD emblem with the hand in a black triangle.
Why is the human body electrically charged?
Especially friction ensures electrostatic charge. We know this from the child experiment with a balloon, which causes friction to make the hair of the head stand on end. But also from driving a car: Some synthetic fibres in clothing load the driver by electrostatic chafing on the car seat. Since no discharge is possible in the car (Faraday cage, so shielded by the rubber tires to the earth), the voltage difference to the environment continues to grow. Only when the driver is "grounded" at the exit and touches the metal of the car, the tension built up by his body can compensate. It works like a lightning bolt that "seeks" a building or a tree on earth at atmospheric voltage differences and can cause serious damage.
A known form of such static electricity discharge is lightning discharge during thunderstorms. Before a discharge (equipotential bonding) can occur, an electrostatic charge must have taken place. This occurs in nature in that light drops of water and ice crystals are carried upwards by thermal updrafts. The particles rub against each other and exchange charge in the form of electrons. When the voltage in the cloud becomes too high, it discharges through the air to the neutral earth.
Charging of the human body occurs by walking with rubber or plastic soles over plastic or carpeted floors, wearing clothing with synthetic fibres, getting up from seating, etc.
Electrostatic discharges of the human body can cause damage in microelectronic components, because in proportion to the component size, the energy of a static discharge behaves in a semiconductor like the energy of a lightning strike in a tree.
Formation of the electrostatic charge
Physical basics
Electric charge - charge carriers
The Bohr atomic model describes the charge of the atomic nucleus as positive and the charge of the electrons as negative.
The positive elementary charge of the atomic nucleus is just as large as the negative elementary charges of the electrons. The atom is neutral to the outside.
Electrically neutral atoms have as many positive as negative electrical charges.
If an atom gives off electrons, the atom has more positive charges than negative ones. It is thus positively charged and exerts an electrical effect to the outside and attracts negative charges.
If an atom absorbs electrons, it is negatively charged and attracts positive charges.
Positively or negatively charged atoms or atomic groups are called ions.
Contact Charge
In order to charge a body (human or material) electrostatically, charges must be separated.
This requires contact and the subsequent separation of materials. Contact refers to the molecular distance of the material surfaces, so that electrons can be released from one material to another or absorbed.
Determining parameters for the height of the remaining charge are the separation rate and the specific material properties.
In addition, surface roughness, surface geometry and material moisture affect the remaining charge level. Other variables include the surface resistance, which in turn is strongly influenced by the humidity and contamination by foreign substances.
Charging of people
Charges occur in people by walking tension when walking, by garment friction, when changing clothes, movements in the workplace, when getting up from chairs, when dealing with plastics, by bulk or filling.
Influencing factors
This maximum safety value applies in ideal conditions in dust-free, climate-neutral rooms with low humidity. These and other factors can have a significant impact on the performance of the PEZZOL ESD shoes. Please use only original insocks which are certificated together with the PEZZOL safety shoes.
It should also be noted that any external changes to the shoe e.g. inserts, bending, dirt and dampness can have a negative influence on the protective function of the shoe and require the ESD shoe to be checked to ensure that its electrostatic discharge features are retained.
- Series insocks and orthopedic insoles or footbeds must not adversely affect the electrical resistance
- Dust
- Climate - Temperature
- Climate - Humidity
- Type of floor (Epoxid - Magnesit - etc.)
Advice
An on-site inspection by a security expert is strongly recommended.
Caution
Antistatic and ESD shoes do not offer guaranteed protection against electric shocks.
In addition to the indoor climate and the degree of soiling, the material and surface of the floors, the intrinsic resistance of components and apparatus at the workplace but also their use can change the actual antistatic conditions. PEZZOL ESD safety shoes therefore recommends regular climate measurements, strict cleanliness and ESD-optimized workstations to ensure complete safety against unwanted discharges.
Scientific tests prove that most people are unaware of the effects of a spontaneous discharge in the technical area: while 3000 volts of voltage on the body will mean a fatal electric shock, only 100 volts is required to delete a magnetic disk, and only 50 volts provide enough energy to ignite with a spark of gas or very fine dust.
In contrast to the flowing charge in an electrical circuit, static electricity is a static charge.
As a rule, it only becomes noticeable when it comes to charge balance between two bodies with different potential.
Although the voltage in electrostatic charges of persons or material can be more than 10.000 V, it is harmless to humans because of the low energy.
But it is sufficient to damage semiconductor devices or assemblies constructed therewith.
ESD Floor
Dissipative footwear causes a reduction of electrostatic charge on normal floors, a safe protection is only guaranteed in connection with a conductive floor.
All floor systems consist of a layer of primer, levelling compound, conductive layer and conductive top layer. They differ mainly in the material composition of the top layer, the layer thickness and laying technology execution.
Dissipative footwear must also be tested in conjunction with the floor, whether the charge resulting from walking by step voltage remains less than 100V and in <1 sec to the ground potential is derived (walking test according ISO 61340-4-5).
PEZZOL is proven as a partner in electronically sensitive fields of work.
For people who work in the microelectronic field or with high-frequency technology, apart from absolute cleanliness at the workplace, above all the protection of product and working material against electrostatic influences counts. This is especially true in semiconductor technology, the automotive industry, in physical research laboratories or in electromedicine. That is why experienced technicians and engineers in particular rely on the ESD PEZZOL safety shoes.
ESD = Electro Static Discharge
The ESD PEZZOL safety shoes actively ensure a permanent, gentle discharge of the wearer (warning: the ESD range does not have an insulating effect!). - A quality feature that is clearly visible from the outside on PEZZOL ESD shoes through the circular, yellow ESD emblem with the hand in a black triangle.
Why is the human body electrically charged?
Especially friction ensures electrostatic charge. We know this from the child experiment with a balloon, which causes friction to make the hair of the head stand on end. But also from driving a car: Some synthetic fibres in clothing load the driver by electrostatic chafing on the car seat. Since no discharge is possible in the car (Faraday cage, so shielded by the rubber tires to the earth), the voltage difference to the environment continues to grow. Only when the driver is "grounded" at the exit and touches the metal of the car, the tension built up by his body can compensate. It works like a lightning bolt that "seeks" a building or a tree on earth at atmospheric voltage differences and can cause serious damage.
A known form of such static electricity discharge is lightning discharge during thunderstorms. Before a discharge (equipotential bonding) can occur, an electrostatic charge must have taken place. This occurs in nature in that light drops of water and ice crystals are carried upwards by thermal updrafts. The particles rub against each other and exchange charge in the form of electrons. When the voltage in the cloud becomes too high, it discharges through the air to the neutral earth.
Charging of the human body occurs by walking with rubber or plastic soles over plastic or carpeted floors, wearing clothing with synthetic fibres, getting up from seating, etc.
Electrostatic discharges of the human body can cause damage in microelectronic components, because in proportion to the component size, the energy of a static discharge behaves in a semiconductor like the energy of a lightning strike in a tree.
Formation of the electrostatic charge
Physical basics
Electric charge - charge carriers
The Bohr atomic model describes the charge of the atomic nucleus as positive and the charge of the electrons as negative.
The positive elementary charge of the atomic nucleus is just as large as the negative elementary charges of the electrons. The atom is neutral to the outside.
Electrically neutral atoms have as many positive as negative electrical charges.
If an atom gives off electrons, the atom has more positive charges than negative ones. It is thus positively charged and exerts an electrical effect to the outside and attracts negative charges.
If an atom absorbs electrons, it is negatively charged and attracts positive charges.
Positively or negatively charged atoms or atomic groups are called ions.
Contact Charge
In order to charge a body (human or material) electrostatically, charges must be separated.
This requires contact and the subsequent separation of materials. Contact refers to the molecular distance of the material surfaces, so that electrons can be released from one material to another or absorbed.
Determining parameters for the height of the remaining charge are the separation rate and the specific material properties.
In addition, surface roughness, surface geometry and material moisture affect the remaining charge level. Other variables include the surface resistance, which in turn is strongly influenced by the humidity and contamination by foreign substances.
Charging of people
Charges occur in people by walking tension when walking, by garment friction, when changing clothes, movements in the workplace, when getting up from chairs, when dealing with plastics, by bulk or filling.
Influencing factors
This maximum safety value applies in ideal conditions in dust-free, climate-neutral rooms with low humidity. These and other factors can have a significant impact on the performance of the PEZZOL ESD shoes. Please use only original insocks which are certificated together with the PEZZOL safety shoes.
It should also be noted that any external changes to the shoe e.g. inserts, bending, dirt and dampness can have a negative influence on the protective function of the shoe and require the ESD shoe to be checked to ensure that its electrostatic discharge features are retained.
- Series insocks and orthopedic insoles or footbeds must not adversely affect the electrical resistance
- Dust
- Climate - Temperature
- Climate - Humidity
- Type of floor (Epoxid - Magnesit - etc.)
Advice
An on-site inspection by a security expert is strongly recommended.
Caution
Antistatic and ESD shoes do not offer guaranteed protection against electric shocks.
In addition to the indoor climate and the degree of soiling, the material and surface of the floors, the intrinsic resistance of components and apparatus at the workplace but also their use can change the actual antistatic conditions. PEZZOL ESD safety shoes therefore recommends regular climate measurements, strict cleanliness and ESD-optimized workstations to ensure complete safety against unwanted discharges.
Scientific tests prove that most people are unaware of the effects of a spontaneous discharge in the technical area: while 3000 volts of voltage on the body will mean a fatal electric shock, only 100 volts is required to delete a magnetic disk, and only 50 volts provide enough energy to ignite with a spark of gas or very fine dust.
In contrast to the flowing charge in an electrical circuit, static electricity is a static charge.
As a rule, it only becomes noticeable when it comes to charge balance between two bodies with different potential.
Although the voltage in electrostatic charges of persons or material can be more than 10.000 V, it is harmless to humans because of the low energy.
But it is sufficient to damage semiconductor devices or assemblies constructed therewith.
ESD Floor
Dissipative footwear causes a reduction of electrostatic charge on normal floors, a safe protection is only guaranteed in connection with a conductive floor.
All floor systems consist of a layer of primer, levelling compound, conductive layer and conductive top layer. They differ mainly in the material composition of the top layer, the layer thickness and laying technology execution.
Dissipative footwear must also be tested in conjunction with the floor, whether the charge resulting from walking by step voltage remains less than 100V and in <1 sec to the ground potential is derived (walking test according ISO 61340-4-5).
