Loss of mass or volume of shoe components (e.g. soles, shaft leather) during mechanical stress.
Resistance of the material to loss of mass or volume. The European standard specifies the minimum wear resistance for the following shoe components: Vamp lining and quarter lining, insole and outsole. Wear resistance is one of the basic requirements of the EN.
The name comes from an adhesive developed by an Italian chemist at the beginning of the 20th century. This adhesive dissolved with acetone is able to bond leather to leather. AGO = Another Great Opportunity.
Bonding process for connecting shaft and insole based on the AGO adhesive. The AGO process forms the basis for the adhesive technology used today. In the AGO procedure, the lasting edge of the shoe shaft is fixed underneath the insole by gluing (glued lasted).
Component extracted from coal tar. Aniline is the starting material for many dyes. Even today, when using transparent dyeing processes with water-soluble substances, one still speaks of aniline dyeing, although the component aniline is usually no longer contained for environmental reasons.
Leather without topcoat, dyed exclusively with water-soluble aniline dyes. Because no opaque colours are used, the grain structure of the leather is clearly visible. The natural character of the leather is preserved.
On PU runners, the sole material polyurethane is injected into the respective injection mould and, in this way, foamed directly onto the shoe shaft as a midsole and/or outsole.
The term “antistatic” defines the range of electrical contact resistance. For antistatic shoes, it shall be not less than 100 kΩ and not greater than 1000 MΩ in both a dry and a humid atmosphere. If the body has become electrostatically charged, a painful discharge can occur when touching other people or metal objects. Antistatic footwear is recommended if the electrostatic charge should be reduced. Safety shoes are always equipped with antistatic outsoles and midsoles. Changing the manufacturer’s removable insole to any other sole can lead to the loss of all antistatic properties of the safety shoe (see also the information on “Permanent Antistatic”). Of course, the Texon insoles used are also antistatically equipped.
During the vulcanisation process, a rubber compound is formed into a shoe base under the influence of pressure and heat and bonded to the shoe shaft.
Term from leather production. Liming is a working process in the water workshop of a tannery. The hides are cured. Limping involves the loosening of the fibre structure, the epidermis, and the hair as well as the partial removal of fatty substances and proteins. The name liming is derived from lime (calcium hydroxide). This operation is essential for the later properties of the leather.
The lasted or strobelled shaft is placed on a last (e.g. for injection moulding of PUR-DUO soles). The inserted last is firmly attached to the machine.
The surface of the shoe part in question is roughened to optimise the adhesion of adhesives or other compounds. The nitrile rubber outsoles, for example, are chemically roughened by means of an adhesion promoter (see halogenation) to ensure better adhesion with the PUR midsole which is injected later. The shaft edge of the shoes is also roughened (edge roughening) to ensure lateral adhesion of the injected PUR sole. By roughening the lasting edge, the smooth grain layer of the leather is removed, thus increasing the adhesive surface. The adhesive can adhere better.
Incorrect roughening can lead to sole or sole edge detachment.
A cavity is created by fixing the lasting edge under the insole. The cavity is then filled. In this way, a smooth sole contact surface is restored. Cork filling pieces are often used for filling.
When laying out, the individual shaft components are placed on the animal’s skin. Various quality aspects must be taken into account (see explanations on skin structure and punching).
During the production of injection-moulded or vulcanised soles, sole material may escape from the mould after the required filling quantity has been reached. This results in the flash. This protruding material is removed with the appropriate tools.
Construction shoes meet the requirements for safety shoes according to safety level S3. In addition to the basic requirements, they meet the following additional requirements:
Closed heel area
Energy absorption capacity in the heel area
Requirements regarding water absorption and water penetration
Resistance to penetration
Tread pattern of the outsole
Construction shoes have a raised insole and an angled stainless steel midsole. This steel midsole protects the wearer’s feet, especially against the penetration of sharp or pointed objects (e.g. nails) into the shoe. The set-up provides additional protection in the particularly sensitive inner area of the foot. The steel midsole is angled in order to significantly improve the rolling comfort.
Occupational shoes (for the commercial sector)
Occupational shoes for the commercial sector is standardised according to EN 347. It does not need to have a toe cap. If a toe cap is present, it is not subject to testing. The individual safety levels are marked with O1, O2, O3, (O stands for occupational).
Components of safety shoes:
See fatigue bending behaviour.
A piping is a strip of leather that is sewn on as an ornament when the shaft parts are sewn together.
Designation for the front part of the shaft of a shoe (see components of safety shoes).
Inner lining of the front part of the shaft.
Depending on the design of the shoe shaft, a distinction is made between different shaft designs. With an Oxford, the front part of the shaft (vamp) is stitched to the rear part of the shaft (quarter). The leather cut edges of the vamp can be recognised by the finished quilted shoe shaft.
Rawhide that has not yet been tanned. Pelt is the term used to describe the hides and skins that have undergone the working processes of the water workshop but have not yet been tanned (i.e. all non-tannable components of the skin have been removed). The hides and skins are in a tanned condition.
Abbreviation for the shoe base or the bottom part of the shoe (see components of safety shoes).
The insole is one of the inner base parts of the shoe. According to the provisions of EN 344, the insole must be incorporated into the shoe construction in such a way that it cannot be removed without destroying the shoe. The insole connects the shaft with the base of the shoe. The shaft of the shoe is sewn to the insole or AGO-lasted far below the insole depending on the design. Below the insole, the midsole and outsole are injected or glued on. Depending on the type of shoe, a steel midsole and/or an ankle joint with a cushioning element may also be fitted between the insole and outsole. The insole is highly important for the quality of the shoe because a high degree of strain is caused by foot sweat, and the insole must last for the entire life of the safety shoe. In order to meet these special requirements and to offer the wearer the greatest possible comfort, leather insoles or insoles made of antistatic material are used. According to EN regulations, the insole must have a minimum thickness of 2 mm. For leather insoles, the pH value shall not be less than 3.5. In addition, there are regulations for wear resistance, water absorption, and water release capacity.
Textile lining material characterised by a special softness, abrasion resistance, and water vapour permeability.
The new European standards for safety, protective, and occupational shoes for the industrial sector have been adopted by the European Committee for Standardisation. The abbreviation CEN stands for the French name of the committee: Comite Europeen de Normalisation.
Chrome tanning is one of the mineral tanning processes (see tanning processes). The animal hide is transformed into leather using chromium salts. Today most upper and lining leathers are chrome tanned. Chrome tanning is simpler, faster, and cheaper than vegetable tanning. Chrome-tanned leathers also have a more beautiful grain pattern and thus a better appearance. Chrome-tanned leather is about twice as tear-resistant as vegetable-tanned leather. With the introduction of chrome tanning, it became possible to treat split leather in such a way that it is suitable for further processing (e.g. as shoe leather).
Collective term for chrome-tanned leather.
Most leathers are chrome tanned or tanned in combination with other tanning agents. Only chromium salts in the form of non-toxic, trivalent compounds (which are also important for the human body as trace elements) are effective in tanning chrome. Chrome-tanned leathers do not contain any skin-damaging chromates (hexavalent chrome). Chromium salts are obtained from chromium iron ore.
Chrome tanned split leather
“La croupe” = back (French) Croupon is the name for the bend or back piece of animal skin (see skin structure). These are the highest quality zones of animal hide.
Fatigue bending behaviour
The fatigue bending behaviour of a shoe is tested according to a procedure defined by DIN EN 344. This involves stressing an outsole with three stitches in the area of the ball of the foot and then bending it 30,000 times at this point at an angle of up to 90°. If cracks appear during this test, these cracks shall not be longer than 4 mm.
Opaque colours (muted leather)
In contrast to aniline leather, muted leather is treated with opaque colours. The opaque colours consist of pigments, which are applied to the grain surface with the help of a binder. Compared to aniline dyeing, the opaque colours cover the grain structure of the leather. The opaque finish increases the resistance of the leather and offers the possibility to cover possible defects in the skin. Leather with an opaque colour application is referred to as opaque leather.
Cover soles are part of the interior of a safety shoe. They cover a part of the insole in the inner part of the shoe and increase the comfort for the wearer. As a rule, half foot beds are used; these are equipped with a joint pad to improve stability in the inner foot area.
This is a special shaft cut. In contrast to the Oxford, the rear part of the shaft (quarter) is sewn onto the front part of the shaft (vamp). The cut edges of the quarter parts are visible.
DIN = Deutsche Industrie Norm [German Industry Standard]. DIN 4843 was the standard for protective shoes valid until the end of 1994. DIN 4843 has been replaced by the new European Standard. (EN 344 - 347), which was already valid in the transition phase from January 1993. For the time being, Part 100 of DIN 4843 remains valid for the definition of the slip resistance of sole materials because no complete European solution has yet been found here.
Three-layer lining material for a pleasant foot climate. Because of the composite of hydrophobic and hydrophilic fibre layers, moisture produced inside the shoe does not accumulate. Hydrophilic fibres absorb moisture and transport it to the layers facing outwards. The hydrophobic layer facing the interior always feels dry, while the hydrophilic layer ensures that moisture is removed. DRI-LEX® is colour-fast and extremely abrasion resistant.
Generic term for all two-layer soles. DUO soles consist of a step-elastic PUR midsole combined with a more highly compressed PUR outsole, a TPU (thermo-plastic polyurethane) outsole, or a nitrile rubber outsole. The step-elastic midsole ensures good wearing comfort through high shock absorption, and the outsole guarantees important properties such as wear and cut resistance. The use of DUO soles considerably minimises the risk of sole breakage compared with layered soles.
Complete dyeing means that the entire leather cross section is dyed. The tanning colour of the leather is no longer visible.
Resistance to penetration
If the wearer of safety shoes is at risk of stepping on sharp or pointed objects at work, a safety shoe must be equipped with a puncture-resistant base. The penetration resistance is achieved by installing a stainless steel midsole, which is glued between the insole and the outsole or midsole. This prevents foot injuries caused by the penetration of sharp objects into the shoe interior. Safety shoes according to EN 345 S3 are used mainly in the construction industry (see construction shoes).
ESD shoes do not protect people but rather electrostatically sensitive components from insufficiently dissipated electrostatic energy. The contact resistance of ESD shoes is 105–107 Ω.
Many safety shoes are equipped with a removable insole. The insole is precisely matched to the shoe size and shoe shape and thus cannot slip. It has an antibacterial (sanitised) finish and is washable up to 40°C. This effectively supports the foot hygiene of the shoe wearer. The removable insole is anatomically shaped and also serves as a foot bed. This sole can be replaced and reordered.
Electrical contact resistance
In terms of electrical contact resistance, EN 344 distinguishes between conductive and antistatic shoes. The corresponding values for the permissible contact resistance are explained under the respective terms “antistatic shoes” and “conductive shoes”. The contact resistance is measured by filling the test piece with 4 kg steel balls and placing it on a copper plate. A test voltage of 100 V DC is applied between the copper plate and the steel balls, and the corresponding resistance is measured.
Abbreviation for Europäische Norm [European Standard]. Shoes for the commercial sector are standardised according to EN 345 (safety shoes), EN 346 (protective shoes), and EN 347 (occupational shoes). EN 344 contains all the essential requirements for safety, protective, and occupational shoes and specifies the necessary test procedures. The European standards mentioned above have been developed by ENT/TC 161 “Foot and leg protection”.
Energy absorption in the heel area
According to EN 344, the energy absorption capacity in the heel area of safety shoes must not be less than 20 joules. The energy absorption in the heel area is very important in order to relieve joints, prevent accidents, and reduce the consequences of injuries. In order to optimise this particularly important area beyond the requirements of EN 344, additional cushioning systems are used in the heel area.
English shoe size
Shoe length measuring system based on the English inch. The shoe sizes are indicated by numbers from 0 to 14. One length corresponds to ⅓ inch (= 8.46 mm). Labelling e.g. 7 / 7.5 / 8 etc.
A bellows tongue is incorporated, for example, into the upper part of the shaft of high boots. The bellows tongue allows the upper width of the shaft to be individually adjusted to the calf circumference of the wearer and thus contributes to an optimum fit.
The leather hide used for leather production essentially consists of two layers, the grain layer and the fibre layer. The border between the two layers is formed by the ends of the hair pores. The fibre layer consists of coarser fibres than the grain layer. The fibre layer determines, for example, the resistance, density, and tear resistance of the leather, whilst the grain layer determines the appearance of the leather. The fibre layer is the layer facing the flesh side of the skin (see skin structure).
The colouring of leather through the use of different dyes. Depending on the type of dyeing, a distinction is made between different types of leather (see aniline leather and muted leather/cover colours).
The lasting edge of the shoe shaft, which is located in the area of the heel, is attached under the insole. This process is called heel lasting. Only with the AGO method is the fastening carried out on a heel lasting machine using tacks and glue.
Applied to the production of safety shoes, this means that the shoes are subjected to a surface treatment during the finishing process. Special finishing preparations (e.g. shining and polishing agents) are sprayed onto the shoe. The finish is important for the appearance of the leather (make-up of the shoe).
After the individual shaft sections have been sewn together, the protruding thread ends of the shaft seams are singed with a gas flame. This operation is known as singeing.
Side of the hide/leather facing the carcass. “Underside of the leather”. The upper part of the leather is referred to as the hair or grain side.
The flesh split is the lower part of the split leather obtained (see also split leather).
The forestry boot is a high boot made of hydrophobic full cowhide. In addition to the usual safety features of an S2 shoe, the forestry boot is equipped with a saw-resistant intermediate layer in the vamp area, in areas of the quarter, and in the tongue. This takes into account the particular risk of injury during wood and sawing work. It meets the requirements of EN 345 part 2 with respect to protection against cuts by hand-held chain saws with a chain speed of 20 metres per second (cut protection class 1). Furthermore, it is recognised by the Board of Trustees for Forest and Forestry Work, Groß-Umstadt.
Also known as the “Paris point”. A point according to the French length measure is ⅔ cm long. The size of the shoes is indicated by their numbering. From 15 (smallest child size) to 50. With the exception of the Mondopoint system, shoes are marked according to the French size indication (e.g. 39, 40, 41, 42).
Because of its anatomical shape, the foot bed supports the foot inside the shoe. The shape of the foot bed corresponds to the shape of the sole of the human foot and thus ensures a good foot bedding in the shoe. Safety shoes can be equipped with a foot bed. This can be done, for example, by integrating special removable insoles or by an additional joint cushion as part of the leather cover sole inside the shoe.
see following points
maximum distance between toe and heel of the foot
Circumference of the foot measured via the ball of the foot.
Projection of the foot circumference onto a horizontal plane.
Leather for the inner lining of the shoes. A distinction is made between vamp, quarter and tongue lining. The lining leather must have a good absorption capacity, good wear resistance, and resistance to perspiration. A vamp liner is prescribed according to EN 344, but the quarter liner is not mandatory.
Joint pieces or parts belong to the base parts of the shoe. Safety shoes are mainly equipped with a joint below the insole. This joint can be made of plastic, wood, or steel. It is anatomically shaped and thus supports the arch of the wearer’s foot and provides optimised stability in the heel and metatarsal area. The joint part is not used if a steel midsole is fitted because the mode of action is the same in this case.
Tanning means the transformation of animal hide into leather using various tanning agents. The tanning process is a chemical reaction that takes place between protein molecules of the skin and the tanning agents. The networking of the structural chains is irreversible. The tanning process transforms the animal side in such a way that it does not rot when wet, does not break when dry, and cannot be destroyed by hot water.
The tannery is essentially divided into the following areas and operations:
Raw materials warehouse
Control of hides and skins
Soaking (return to the original condition, clean)
Liming (loosening of the epidermis including hair)
Fleshing (mechanical removal of the subcutaneous/fatty tissue)
Pickling (process for preparing the tanning by adding salts)
Tanning according to different methods, mostly in large barrels
Wet preparation (dyeing and greasing)
Drying and staking (softening)
Dry preparation (folding and splitting)
The most important tanning processes:
Combination of all three
Extract from leaves and bark containing tanning agents
Synthetic tanning agents
Combination of the two
Combination of mineral and vegetable tanning
Fat tanning with whale oil and synthetic fats
Leather of which surface has been buffed. Depending on which side of the skin has been buffed or on the amount of buffing, a distinction is made between different types of buffed leather (see also corrected grain leather, nubuck leather, roughout leather).
This is a special boot from the safety shoe range. The shoe has safety level S, a hydrophobic grained cowhide upper leather, and a nitrile rubber sole. The special feature of the shoe is a special closure system that allows the wearer to remove the foundry boot very quickly in certain emergency situations.
Chemical roughening for improved adhesion of adhesives. Nitrile rubber soles are chemically halogenated with an adhesion promoter to ensure the best possible adhesion to the foamed PUR midsole.
Skins of large animals such as cattle or horses are known as hides; skins of sheep or calves, on the other hand, are called skins.
With respect to skin structure, there are three main layers:
Subcutaneous connective tissue
The epidermis with the hairs is removed by liming before the tanning process; the subcutaneous connective tissue is separated mechanically by fleshing. Only the dermis is used for leather production.
The dermis in turn is composed of the grain layer (upper skin layer) and the fibrous layer (lower skin layer). The boundary between the two layers is formed by the ends of the hair or bristle skins. The grain layer consists of a very fine fibre net. This determines the appearance of the leather through the arrangement of the hair pores. The fibre layer is composed of coarser fibres.
Skin structure (tannery)
Depending on the balance of the skin fibre structure, different quality zones are distinguished in animal skin. The most valuable part of the hide is the bend or croupon. The thickness and structure of the leather is uniform here, and all physical properties have the best values. For this reason, the vamps of the shoe shaft are punched from the bend piece because this is where the greatest stress occurs in the creases. Towards the flanks and the neck, the physical properties decrease; the structure of the skin changes. Qualitatively less stressed shaft parts can also be cut from these skin zones.
The heel cap is one of the shaft components of a safety shoe. High-quality Lefa (leather fibre material) heel caps and thermoplastic heel caps are used. The heel caps are inserted by hand in the heel area of the shaft and then moulded in a heel cap moulding machine. Lefa heel caps give the foot the necessary stability in the heel area when walking and standing and keep the shoe in shape in the heel area.
The impregnation of leather is referred to as hydrophobisation. The leather is treated with an impregnating agent that coats the individual leather fibres and pores, making them water repellent. However, the spaces between the individual fibres remain free. This ensures good water resistance as well as good water vapour permeability. Depending on the requirements of the finished shoe, there are different levels of hydrophobisation. In any case, safety shoes according to S2 are equipped with hydrophobic cowhide leather in order to meet the requirements of the EN in terms of water penetration, water absorption, and water vapour permeability.
Making the leather water-repellent (see hydrophobisation).
ISO 9001:2000 Quality management system
The International Standard specifies uniform requirements for a quality management system in a company. All processes in the company are analysed and documented, and any weak points that may occur are eliminated. Among other things, recurring processes, for example, are simplified by a uniform procedure and thus shortened to the benefit of the customer. The requirements set out in the standard are designed to achieve customer satisfaction by preventing errors at all stages – from development to shipment.
ISO 14001 Environmental management system
The International Standard specifies uniform requirements for an environmental management system in a company. The standard applies to all environmental aspects that the company can monitor and where influence appears possible. The basic idea is to improve the company’s environmental performance or reduce its environmental impact by introducing an environmental management system.
Russia leather is a strongly greased cow or calf leather as an imitation of the leather originating from Russia. Russia leather is waterproof and very supple. It is tanned using birch bark tar and then heavily greased.
Categories of safety shoes
The new European Standard makes a fundamental distinction between basic and additional requirements. The majority of the safety shoes used meet one or more additional requirements in addition to the basic requirements. For this reason, the structure of the labelling of safety shoes has been simplified by standardising certain possible combinations in the form of short symbols. For safety shoes according to EN 345, the following applies:
S1: Safety shoe that, in addition to the basic requirements of EN 344, also meets the additional requirements of closed heel area, antistatic, and energy absorption capacity in the heel area.
S2: like S1 but water penetration and water absorption is also required.
S3: like S2 but penetration resistance and the tread of the outsole is also required.
Safety shoes for winter or cold use protect the wearer against the cold through the cold insulating properties of the PUR soles in combination with additional warming insoles. In addition to the corresponding safety categories, these shoes are also marked with the “CI” suffix for cold-insulating.
Labelling according to CEN
Safety shoes must be marked with the following information according to the EN regulations:
Mark of the manufacturer
Type designation of the manufacturer
Date of manufacture (at least quarter and year)
Number of the applicable EN
Symbols corresponding to the protection function
Designation for the qualitatively best piece of animal skin (see skin structure).
Combined tanned leather
Leather tanned with at least two different tanning agents (e.g. chrome tanning with vegetable retanning; see tanning process).
Corrected grain leather
Corrected grain leathers are leathers where the grain layer has been lightly sanded (e.g. to remove imperfections).
With rubber outsoles of safety shoes, there is a risk that marks difficult to remove from the floor covering are created by the abrasion of the rubber. One speaks of the shoes “scuffing”. Shoes with PUR outsoles have the advantage that they do not scuff.
Part of the shoe shaft. Tongues are sewn on in the closure section of the shaft and thus prevent foreign bodies from penetrating the inside of the shoe. Safety shoes in boot form are often additionally equipped with a dust tongue closed at the side. In addition, the tongues of the shoes are still largely padded to prevent pressure points in the instep area. According to EN 344, the tongue must meet basic requirements with regard to tear strength and pH value.
The outsole is the sole that is in direct contact with the ground. The outsole material offers an extensive range of problem and application solutions for safety shoes:
Nitrile rubber soles
The nature and properties of the outsole material are crucial for the selection of individual safety shoes for specific purposes. As basic requirements for the outsole, EN 344 specifies the thickness, tearing force, wear resistance, bending behaviour, hydrolysis, fuel resistance, and the separating force between the layers in multi-layer soles. The outsole must also be sufficiently firmly attached to the shaft construction.
General term for animal hides and skins that have been rendered imperishable by tanning (see tanning). Leather production is one of the oldest crafts in the world. Leather is a versatile natural product, which is characterised in particular by its flexibility, toughness, malleability, and stretchability. Leather is also soft, breathable and hard-wearing. Leather is processed to make shoes, jackets, trousers, furniture, gloves, and occupational safety articles, among other things.
Today, more than 200 different types of leather are known. A subdivision of the individual leather types can be made as follows:
by the origin of the raw hide/animal species (e.g. cowhide, pigskin)
by the split condition (grain leather or split leather)
by tanning (chrome leather, vegetable leather, chamois leather, combined tanned leather)
by dyeing (aniline leather, muted leather)
by finish (full grain leather, corrected leather, buffed leather)
by the intended use (shoe leather, furniture leather)
The part of the skin that can be used for leather production (see skin structure).
Abbreviation for leather fibre material. Safety shoes are equipped with rear caps made of high-quality Lefa material (see heel cap).
The last is the most important tool for the production of safety shoes. In principle, it is a replica of the human foot. The last is the shaping tool that determines the inner dimensions and outer shape of the shoe. The insole construction forms the outline of the last. Foot length, foot width, and ball circumference are in a certain relationship to each other. Mouldings are made of different materials (e.g. wood or plastic). They must meet a wide range of requirements with regard to fit and foot-friendly construction.
According to the EN regulations, conductive shoes may have an electrical contact resistance of max. 100 kΩ under defined conditions (see electrical contact resistance).
Safety shoes made of the material Lorica are washable. The upper and lining material Lorica is a microfibre material impregnated with special resins and can be washed at 60°C at least 10 times. Because they are washable, Lorica shoes are in demand wherever high standards of hygiene are required (e.g. food industry, nuclear power plants, laboratory areas).
By cut, we mean the way the shaft and base of the safety shoe are connected. With regard to safety shoes, there are essentially two different types of cuts: Strobel cut and AGO lasting (see AGO, see Strobel cut).
Certain tanning process in which mineral tanning agents such as chrome, aluminium, or iron are used (see also tanning process).
Safety shoes have differently shaped metatarsal pads in the area of the steel cap transitions. The padding prevents the development of pressure points in this area and additionally improves the comfort for the wearer.
The main steps in the development of a new model can be outlined as follows:
Preparation of shoe sketches and model coordination with the sales department (two-dimensional drawing)
Transfer of the model to a pullover last taped with adhesive tape (three-dimensional lasts)
Making a copy of the last (surface of the last is placed on one plane, two-dimensional surface)
Creation of the basic model via CAD
Preparation of templates and sample slips
Bill of material creation and calculation
The Mondopoint system is the only internationally comparable metric measurement system. It takes into account the fact that human feet are not only different in length but also in width. In order to achieve the best possible fit for the wearer, Mondopoint shoes allow the right foot length to be combined with four different widths. In the Mondopoint system, the foot length and the foot width are given in millimetres (example: 270/100).
The Mono-PUR sole is an outsole made of single-layer, microcellular polyurethane (see sole types).
Often leather that has already been tanned is subjected to a further tanning process – retanning. This is to adjust very special properties of the leather (see combined tanned leather).
The uppermost layer of the leather surface forms the grain. The grain shows the characteristic pore pattern for each animal skin. With natural grain, the origin of the leather can be identified by the arrangement of the individual pores according to the animal species.
Grain leather is leather in which the grain layer has been fully preserved. The grain side is not sanded. Grain leather has an elegant natural look. Grain leather has a closed structure. The underside of the grain leather is rough.
During the splitting process, the skin is divided in thickness over the entire surface. The upper part of the split skin, which carries the grain layer, is referred to as the grain split (see splitting).
Nubuck leather belongs to the group of full-grain leathers. This is a grain-side buffed leather. By sanding the finely structured grain layer, a high-quality leather with a velvety character is created.
See skin structure
Generic term for all leathers used for the outer shoe uppers in the shaft area. EN 344 no longer makes the use of leather as an upper material for shoe manufacturing mandatory. Similarly, there is no specification on the thickness of the upper material within the framework of EN 344 (see materials).
The unique lining material Outlast® is a development from the research laboratories of NASA and is exceptionally temperature regulating. Outlast® ensures a constant temperature regulation in the shoe and balances out fluctuations in heat and cold. This prevents unpleasant sensations caused by high temperatures or cold feet during rest periods.
How Outlast® works:
Outlast® contains millions of microcapsules specially anchored in the high-tech lining. Temperature fluctuations are balanced out very quickly; excess heat is absorbed, stored in the microcapsules, and released back to the foot as required. Outlast® thus provides true temperature regulation without the need for additional vents, insulating padding, or the like.
The eyelets are inserted into the eyelet strips in the closing area of the shaft. They serve as a guide for the laces of safety shoes. Corrosion-resistant eyelets are mainly used beyond the requirements of the EN, thus extending the service life of shoes and laces.
A good fit is one of the most important criteria of a safety shoe. It expresses nothing other than that the shoe is optimally adapted to the conditions of the human foot. However, the assessment of the fit is also very much subject to the personal assessment criteria of the shoe wearer. The fit of the shoe is determined by the last used. It ensures a secure hold in the shoe. A fit that is not correct for the feet can lead to tripping and twisting accidents and even orthopaedic damage to the feet.
Permanent antistatic (PAS)
Safety shoes according to EN 345-1 are antistatic. The antistatic properties of conventional safety shoes are achieved by attaching a copper strand to the insole. If the safety shoe is equipped with a full removable insole, this must also be antistatic. If the removable insoles are changed, make sure that appropriate antistatic removable insoles are used again. Often other removable insoles are used, and the antistatic properties prescribed for safety shoes are lost. This considerably increases the risk of injury to the shoe wearer depending on the area of risk.
Safety shoes from the manufacturer Baltes with PAS system for permanent antistatic solves this problem. By means of a special process, antistatic properties are achieved not only by the sole connection. The surrounding shaft is also included. No matter which removable insole you use, the safety shoe achieves the antistatic value of 106 Ω.
Abbreviation for Prüf- und Forschungsinstitut [test and research institute] für die Schuhherstellung. At the PFI in Pirmasens, safety shoes are tested in accordance with the provisions of the European Standard.
Vegetable tanning is a specific tanning process in which the animal hide is transformed by means of vegetable tanning agents (see tanning process).
The pH value is a measure of the strength of the acidic or alkaline reaction (i.e. the pH indicates whether a solution is acidic, alkaline, or neutral). A neutral pH value is of great importance for skin compatibility. A pH value less than 7 is in the acidic range, a pH value of approx. 7 is called pH neutral, and a pH value above 7 is in the alkaline range. According to the regulations of EN 344, leather parts used in safety shoes must have a pH value of at least 3.5. In order to avoid acidic reactions inside the shoe, TEXON insoles, for example, which have a largely neutral pH value of 7–8, are used. This considerably reduces the frequently observed foot burning.
Among the comfort aspects, the area of padding plays a very central role in safety shoes. Upholstery materials are used, for example:
Middle foot padding to prevent pressure points in the area of the steel cap transitions
Shaft edge padding
pronounced ankle pads for protection against mechanical impacts
Tongue padding to prevent pressure points in the instep area
Joint padding to support the inner foot area
Heel padding in the shoe interior
With the help of embossed metal plates (grain plates), for example, a split leather can be provided with an artificial grain structure. The grain artificially applied in this way is called pressed grain. Today, split leather can be treated by pressing grain in such a way that it is very difficult to tell the difference from grain leather.
Treading of the outsole
Safety shoes are equipped with a sophisticated tread that ensures optimum slip resistance. Also in the joint area of the outsole, the tread pattern is improved in terms of slip resistance through the addition of crosspieces. The shapes of most shoes are also provided with bevelled tread edges. They cause a self-cleaning of the spaces between the treads.
Abbreviation for polyurethane. PUR is a special material for foaming midsoles and outsoles to the shaft structure of shoes. A further development of polyurethane is TPU (thermoplastic polyurethane).
Machine for injection moulding of PUR soles (see foaming).
Lasts for the production of models and prototypes. The name pullover last is due to the fact that a sample shaft is pulled over the last.
Quality zones of the leather
See skin structure
Designation for the rear part of the shoe shaft (see components of a safety shoe).
In contrast to smooth leather, the surface of full-grain leather is heavily sanded. A distinction is made between grain-side buffed full-grain leather (nubuck leather) and flesh-side buffed leather (velour). Nubuck leather has a fine, velvety character because the finely structured grain layer is sanded. Roughout leather is more coarse-grained because the coarser fibre layer on the flesh side has been sanded.
For the production of full-grain leather, cattle hides of a certain size and above are used. A special tanning process makes the full-grain leather particularly full and strong. Full-grain leather can be smooth or grained, with a muted and shiny surface.
Generic term for leather made from cattle hides. The thickness of cattle skin can vary between 2 and 6 mm. Cowhides have an unevenly distributed grain pattern. Leather parts in safety shoes consist mainly of cowhide, namely full cowhide.
The term rawhide refers to the skin that has not yet been tanned. It may be in a fresh or preserved state.
As part of a safety shoe range, various sandals with buckle or Velcro fasteners are also offered. Because of perforations in the quarter, sandals are especially characterised by the good air circulation. They are therefore ideally suited for use indoors or in warm summer temperatures.
Removable insoles are “sanitised”. They thus support the foot hygiene of the shoe wearer (see removable insole).
A leather obtained from Chamois tanning (see tanning process). The tanning agent used is mainly whale oil. Chamois leather is used as shammies, among other things.
Pollutant tested mark (SG mark)
The leathers used in the manufacture of safety shoes require the use of chemicals in processes such as dyeing, tanning, storage, and transport preservation. It is therefore important to ensure careful production and the use of materials that are free of pollutants or low in pollutants. Some models from our product range have been awarded the SG mark (Schadstoff geprüft; tested for harmful substances) by “TüV Rheinland Berlin Brandenburg”. This is a voluntary test for harmful substances that far exceeds the standard requirements. This test confirms that, according to current knowledge, the safety shoes tested do not contain any substances of concern to the wearer. Every single element of the safety shoe – from the eyelet to the lining to the sole – has been examined in detail in accordance with strict requirements regarding limit values and harmful substance parameters. The SG mark provides additional security. The manufacturer of these models is currently (As of June 2003) the first and only producer in Germany whose products feature this test mark.
The upper part of the shoe above the sole (see components of a safety shoe). The shoe shaft is sewn from individual shaft parts. The most important parts of the shaft are vamp and quarter leather as well as upper and lining leather, tongue parts, tucks, padding, toe cap, and heel cap. The individual leather parts of the shoe shaft are joined together in the quilting department. EN 344 distinguishes different shoe shapes depending on the height of the shaft:
Low shoe (A)
Boots, low (B)
Boots, half high (C)
Boots, high (D)
Boots, thigh high (E)
The basic material for the shaft is no longer prescribed by EN 344. In other words, materials other than leather can be used (e.g. LORICA). The upper of the shoe must meet basic requirements with regard to tear strength, firmness, water vapour permeability, water vapour index, and pH value for leather.
Safety shoes with particularly high shafts (shaft height over 20 cm). Typical high boots articles from the winter/cold range. High boots additionally protect the calf area of the wearer.
The edges of the individual parts of the shaft are ground (i.e. the edges are bevelled by means of a grinding machine), thereby removing approx. 50% of the thickness of the leather. Grinding is necessary so that no thick bulges are created when the shaft parts are sewn together.
Cut resistance defines the resistance of the outsole to sharp objects and particles (e.g. shavings and glass). TPU outsoles, nitrile rubber outsoles, and vulcanised nitrile soles are highly cut-resistant. They are therefore also suitable for use in machining areas the glass industry.
A distinction is made between measures of length and width (see Mondopoint, English shoe size, French point).
After the introduction of the EN, the previous DIN 4843 protective shoes are now protective shoes according to EN 345. The term “protective shoes” was valid from the beginning of the 1980s in connection with the introduction of DIN 4843. However the term protective shoes also exists in the new EN 346, namely for shoes for commercial use that must have a protective toe cap tested with a test energy of 100 joules. This means that EN 346 protective shoes should be placed qualitatively below safety shoes with a 200 joules toe cap. Protective shoes of the current definition are standardised according to EN 346 and are marked in the individual safety categories with PB (protective basic), P1, P2, and P3.
Leather from pigs. Pigskin is somewhat porous but tough. It is characterised by good breathability because the bristles penetrate the entire skin. On the other hand, this fact also means that pigskin is permeable to water. Characteristic for pigskin is the arrangement of the hair bristles in groups of three. Pigskin leather is not divided into grain and fibre layers.
For the commercial sector. Safety shoes are standardised according to EN 345. They shall be equipped with safety toe caps that withstand a test energy of 200 joules during the test. The safety categories are marked with SB (safety basic), S1, S2, and S3. In addition, the safety shoes of EN 345 largely correspond to the former safety shoes of DIN 4843.
Safety toe caps
Safety toe caps are the steel caps for safety shoes according to EN 345. They must withstand a test energy of 200 joules. Various manufacturers now offer models with plastic toe caps. These are also tested with a test energy of 200 joules (see safety shoes).
The soles of the safety shoe belong to the base parts. The following sole types are used in the production of safety shoes:
Insoles, removable insoles, cover soles, and steel midsoles are explained under the corresponding letters:
MONO-PUR soles are single-layer soles made of microcellular PUR. They are free of CFCs and silicone, resistant to oil and petrol, antistatic, and characterised by good cold and heat insulation. In addition, the MONO-PUR sole is step-elastic and flexible and can be used in a temperature range from −18°C to +140°C for short periods. PUR soles are microbe-resistant and do not scuff.
DUO-PUR/PUR soles consist of a step-elastic PUR midsole with high shock absorption and a more dense PUR outsole. The outsole is oil and petrol resistant, CFC and silicon free, and microbe and abrasion resistant. It can be used in temperature ranges from −18°C to +160°C. It does not scuff and is resistant to many chemicals.
DUO-PUR/nitrile soles consist of a step-elastic PUR midsole with high shock absorption and an outsole made of nitrile rubber. The nitrile rubber sole is characterised by its cut resistance and slip resistance. It is resistant to numerous acids and bases and is heat-resistant up to 200°C. Of course, this type of sole also features antistatic properties. The nitrile outsole scuffs. Because their cut resistance, these soles can also be used in machining areas.
VULCA soles consist of vulcanised nitrile rubber. They are particularly cut-resistant and temperature-resistant up to 200°C and are therefore used in areas where high temperatures occur (e.g. smelting works, foundries, and shipyards).
Cowhides are split over the entire surface because of their thickness as well as to smooth out skin irregularities in the tannery. Special splitting machines that divide the hides horizontally are used for this purpose. Splitting can be carried out on the untanned rawhide, on the tanned pelt or on the dry product. Splitting produces different parts: the upper side with the grain layer (grain split or grain leather) and the lower side (flesh split). Depending on the thickness of the leather, the lower part of the split can be divided again to produce a middle split.
Split leather is the term used to describe the layers produced when the skin is split. A distinction is made between:
Grain split (upper layer of skin that carries the grain – also referred to as grain leather)
Flesh split (lower skin layer without grain)
Middle split (middle layer of skin that occurs when the lower part of the split without a grain layer is divided again)
The middle and lower split layer of the leather (i.e. the layers of skin without natural grain) are commonly referred to as classic split leather. In its original form, this split leather is rough on both sides.
It can be finished by pressing grain in such a way that it is difficult to distinguish it from a grain leather. However, the artificially pressed grain often has a plastic-like smoothness and is not as dimensionally stable as grain leather. Split leather is used in shoe production for the manufacture of low-cost shoes.
See safety toe cap
Stainless steel midsole glued underneath the insole to make the safety shoes puncture proof. A specially angled steel midsole is used for integrating the ErgoPlus energy absorption element. Safety shoes with steel midsole meet the requirements according to S3 of EN 345 (see penetration resistance).
The individual shaft parts for shoe production are cut or punched out of the tanned animal skin. This process takes place with the help of punching knives, which are manufactured exactly according to the shape of the individual shaft parts. When punching out the leather parts, several quality-relevant characteristics must be taken into account in addition to the best possible evaluation:
Depending on the strain on the individual parts of the shaft, the individual quality zones of the skin must be taken into account (see skin structure).
If possible, the shaft parts should be put together in pairs and cut out to ensure that they have the same leather properties (pairing rule).
When punching out the parts, it must be ensured that the leather does not stretch in length. Otherwise the shaft will not achieve a good and durable fit.
Tool for punching the individual leather parts out of the skin.
Tongue closed at the side, fastened in the closing area of the shaft. The dust tongues prevent dust and foreign bodies from penetrating the inside of the shoe. Numerous boots from the range are equipped with a dust tongue.
Part of the production process in which the individual leather shaft parts are sewn together. The quilting of the shafts requires a high qualification of the employees.
A design in which the lining leather and the upper leather of the side and heel parts are sewn flush with the insole. Only the upper leather below the steel toe cap area is lasted under the insole. Shoes in a strobelled design are characterised by low weight and high flexibility. Name comes from the Strobel machine manufacturer.
The parts list contains all the accessories and consumable parts necessary for the manufacture of a particular shoe. The required quantities of the shoe components are also indicated. The parts list is therefore the basis for the calculation of the shoes.
During intensive physical exertion, the body often produces more sweat than can be immediately wicked away by leather shoes. The excess liquid collects in the sock and can only evaporate slowly through the lining, membrane, and upper material. The wearer has an unpleasant feeling of moisture over a longer period of time. This is caused by vaporous and liquid sweat repelled by the socks and lining onto the body. The lining is ill equipped to absorb the moisture. In the case of excess perspiration, the lining in clothing and shoes feels unpleasantly wet for the wearer. Against this background, Sympatex® HIGH2OUT was developed as a particularly effective membrane system consisting of the Sympatex membrane and a highly water-absorbent layer. Sympatex® HIGH2OUT can thus transport sweat in vapour and liquid form. This prevents condensation on the inside as well as the unpleasant feeling of dampness. For every safety shoe wearer, this means considerably better wearing comfort with increased physical performance. When there is less physical activity, traditional safety shoes with Sympatex® perform their full function. Sympatex® HIGH2OUT is also available in 100% waterproof clothing for leisure shoes as well as in special winter protection products. With the Sympatex® HIGH2OUT membrane system, the sweat droplets do not roll off the lining as before. Instead, they are absorbed and spread over a large area of the lining. The same amount of moisture can evaporate outwards from a large surface more quickly than from a small one. The large-area distribution of the Sympatex® membrane ensures that perspiration is quickly and effectively wicked away.
Tacks are small metal pins for attaching the shaft under the insole. The process is referred to as tacking.
Texon is a synthetic fibre fleece with specific advantages for use as insole material. Texon insoles ensure a pleasant foot climate and a high degree of wearing comfort. They minimise the risk of foot burn. Advantages of the Texon insole:
Antistatic (even in 100% dry condition) without the use of additional aids that bridge the outsole
approx. 50% lighter than comparable soles made of natural materials
flexible, tough, and dimensionally stable
good air permeability
excellent wear resistance
high moisture absorption
quick drying (dry virtually overnight)
no discolouration and hardening when exposed to moisture
pH-neutral (pH value of approx. 7–8)
no breeding ground for bacteria
TPU (thermoplastic polyurethane)
TPU is a special form of polyurethane (PUR). It is particularly robust, abrasion-resistant, and elastic. Unlike conventional polyurethane, it does not consist of two components that react with each other to form a foam but rather of a thermally formed granulate. TPU is therefore much more efficient. The material is decisively better than conventional polyurethane in all the properties that characterise a safety shoe (i.e. wear resistance, slip resistance, fatigue bending behaviour).
Part of the closure system of safety shoes. Triangles are triangular shaped parts made of corrosion resistant steel for guiding the laces. The name was created because these metal parts have a triangular shape.
The release agent is required to ensure that the injected sole releases from the sole mould without residue and without damage. There are silicone-free release agents, which are optimally and economically applied to the sole moulds by spraying robots.
Safety accessories foamed at the same time as the outsole. The overcap is attached to the upper leather above the toe cap. The overcap protects the upper leather against premature wear in this critical area. Construction shoes in particular are equipped with an overcap because there is a risk that the upper leather in the front part of the vamp will be quickly damaged. The colour of the overcap corresponds to the sole colour.
Additions to the shaft parts for connecting the individual parts to each other. The lower extension is between 6 and 10 mm wide. A lower extension is necessary when parts of the shaft are quilted over each other.
Vegetable tanned leather is called vegetable leather. Pure vegetable tanned leathers are relatively rare because this tanning process is very time-consuming. Mostly you will find chrome-tanned leather that has been vegetable-tanned. Vegetable leathers are characterised by good moisture absorption.
Roughout leather belongs to the group of full-grain leathers. In contrast to nubuck leather, roughout leather is buffed on the flesh side. It therefore has a coarser fibre structure than nubuck leather. Because the flesh split is used for the production of roughout leather, it is often referred to as roughout leather split.
Part of the leather that carries the grain layer. It has excellent wearing properties and is dimensionally stable and tear-resistant. The use of grain leather increases the wearing comfort for the shoe wearer and extends the life of the shoes.
Leathers that still have the entire grain layer after finishing i.e. the grain is not corrected. Full-grain leathers have a natural look, a full strong handle and good wearing properties. Only flawless hides can be used as full-grain leather.
During the sketching out process, marking lines for attaching seams or parts are applied to the shaft parts.
See sole types
See dust tongue
Part of the tannery. Here, mainly work processes that require a lot of water are carried out (see tannery).
Water absorption/water penetration
According to the regulations of EN 345, the water absorption of shoe upper parts according to safety categories S2 and S3 must not exceed 30% 60 minutes after the start of the test. During this time, no water may pass through the upper part of the shoe. After a further 30 minutes, the water penetration through the upper part of the shoe may not exceed 2 g. To achieve these values, the shoes are equipped with hydrophobic cowhide leather according to S2 and S3. Shoes equipped in such a way can also be used in areas in which the occurrence of moisture is to be expected.
Water vapour permeability/water vapour index
The water vapour permeability of the leather is necessary so that the foot does not sweat too much in the shoe. Both requirements belong to the basic requirements of EN 344 for the upper part of the shoe. The water vapour permeability must not be less than 0.8 mg/cm2 · h). The water vapour index must not be less than 20 mg/cm2.
Designation for highly water-repellent leather. These are mostly chrome-tanned or combined tanned leathers that are impregnated to make them highly waterproof.
Working process in the water workshop of a tannery (see tannery).
Wet blue is the term used to describe chrome-tanned leather in a wet state that is not further treated. It therefore has the typical bluish-green colouring of chrome-tanned leather.
According to classification I, the materials that can be used according to EN 344 are shoes made of leather or other materials. According to classification II, fully moulded or vulcanised plastics are also permissible as materials.
In addition to the length of the foot, the width is an important measure to achieve the optimal fit of the shoes for the wearer. The Mondopoint system allows the right foot length to be combined with four different widths. With all other shoe measurement systems, the foot length is automatically assigned a corresponding width. The width describes the foot circumference over the ball of the foot.
Only full-grain leather made from wild skins (e.g. roe deer, stag) is referred to as suede. Mistakenly, other full-grain leathers such as velour or nubuck leather are often referred to as suede.
High boots additionally equipped with cold insulation (e.g. warming removable insole). Winter boots are available with different sole types: MONO-PUR, DUO PUR/PUR, and DUO-PUR/NITRIL.
The toe clearance describes the space the wearer has inside the shoe underneath the toe cap. The toe clearance is important for comfort and safety reasons. Toe cap
See safety toe cap
Part of leather manufacturing. A distinction is made between wet and dry preparation. After tanning, the leather goes through various processing steps in which the appearance and properties of the leather are influenced. Surface buffing and dye spraying are part of the preparation process. Lasting edge addition at the lower edge of the shaft. The lasting edge is lasted under the insole. Depending on the design, the lasting edge is present at the complete shaft edge (AGO method) or only in the area of the leaf below the toe cap (see strobelling). Lasting
Lasting refers to the attachment of the shaft to the insole. There are different lasting methods depending on the type of construction (see gluing, tacking, and sewing). Midsole
Sole between the insole and outsole. Shoes with a DUO sole have a midsole made of foamed PUR. The midsole is characterised by its high shock absorption and thus provides additional wearing comfort.