S classifications and ESD for safety shoes and safety boots
The marking on your safety footwear tells you which protection has been tested. EN ISO 20345 describes the requirements; the S classification summarises a combination of them. Below you will find the classes according to EN ISO 20345:2022, including the variants with penetration resistance. ESD and comfort technologies are explained separately: they do not mean the same thing as a safety class.
Lightweight and sporty
A sporty shape or a lightweight shoe says nothing in itself about the protection class. A safety trainer can also have a protective toe cap and penetration resistance. The standard marking shows the difference, not the appearance.
How to read the overview
✓ = included in the stated class; — = not required by that class. For S1P, S3, S5 and S7, the table shows the metallic P version. The non-metallic variants are explained below. All classes listed have a protective toe cap tested separately for 200 joules of impact and 15 kilonewtons of compression.
| Property | SB | S1 | S1P | S2 | S3 | S4 | S5 | S6 | S7 |
|---|---|---|---|---|---|---|---|---|---|
| Protective toe cap: 200 J / 15 kN | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Basic slip-resistance test* | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Closed heel** | — | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Antistatic (A) | — | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Heel energy absorption (E) | — | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Metallic penetration resistance (P) | — | — | ✓ | — | ✓ | — | ✓ | — | ✓ |
| Upper material: WPA | — | — | — | ✓ | ✓ | — | — | ✓ | ✓ |
| Whole shoe: WR | — | — | — | — | — | — | — | ✓ | ✓ |
| Cleated outsole | — | — | — | — | ✓ | — | ✓ | — | ✓ |
| All-rubber/polymeric construction with leak-tightness test** | — | — | — | — | — | ✓ | ✓ | — | — |
* The basic slip-resistance test uses ceramic tiles with a soap solution. SR indicates an additional test on ceramic tiles with glycerol. The Ø marking exists for special footwear for which the test is not applicable, such as certain spiked soles. None of these tests guarantees grip on every workplace surface.
** This overview covers typical shoes and boots. Exceptions to the closed-heel and leak-tightness requirements exist for certain low-cut rubber/polymeric shoes of design A. Hybrid constructions fall outside this simplified table.
P, PL and PS: what does the penetration code tell you?
- P: metallic insert, tested with a test nail measuring 4.5 mm in diameter.
- PL: non-metallic insert, tested with a test nail measuring 4.5 mm in diameter.
- PS: non-metallic insert, tested with a test nail measuring 3.0 mm in diameter.
This gives S1P, S1PL and S1PS; for S3, S5 and S7, the non-metallic variants are called, for example, S3L and S3S. A smaller test nail is relevant to thin, sharp objects. The code does not mean an impenetrable sole: the shape and force of a sharp object still have an influence.
Do not mix up 2011 and 2022
EN ISO 20345:2011 uses SRA, SRB and SRC; the 2022 version uses the basic test and, optionally, SR. The old P designation did not yet distinguish between metallic and non-metallic inserts as P, PL and PS do now. WRU has been replaced by WPA. S6 and S7 have been added for combinations with WR. FO already existed as a designation. Under EN ISO 20345:2011, outsole fuel-oil resistance was part of the requirements for S1 through S5. In the 2022 version, FO is an optional additional property.
The year of the standard therefore matters when interpreting the code. EN ISO 20345:2022 also has amendment A1:2024. This page explains the consumer markings listed; it does not replace the full standard or a task-specific assessment.
Reading additional properties
The codes below describe properties tested separately. Some are already included in an S classification, while others are optional. The combination of class and additional codes therefore tells you more than the S number alone.
| Code | Tested property | Practical meaning |
|---|---|---|
| AN | Ankle impact protection | Protects the ankle against impact; not a claim about preventing sprains. |
| M | Metatarsal protection | Additional protection over the foot, behind the protective toe cap. |
| CR | Cut resistance | Tested resistance to cutting into the footwear upper. |
| SC | Scuff-cap abrasion resistance | Protection against abrasion on the outside of the toe area. |
| LG | Ladder grip | Outsole requirements for grip on ladder rungs. |
| SR | Additional slip resistance | Tested on ceramic tiles with glycerol. |
| CI | Cold insulation of the sole complex | Limits heat loss through the sole in cold conditions. |
| HI | Heat insulation of the sole complex | Limits heat transfer through the sole. |
| HRO | Outsole resistance to hot contact | Relates to contact with a hot surface. |
| FO | Outsole fuel-oil resistance | Concerns the sole and fuel oil, not fire resistance. |
| WR | Water resistance of the whole shoe | The assembled shoe is tested. |
| WPA | Water penetration and absorption of the upper material | Concerns the upper material, not the entire shoe construction. |
| A | Antistatic properties | Dissipation of electrostatic charge; not the same as ESD or electrical insulation. |
| C | Partially conductive footwear | Low electrical resistance for charge dissipation, not insulation against electric shock. |
| E | Heel energy absorption | Tested shock absorption in the heel area. |
| P / PL / PS | Penetration resistance | Insert type and test nail as explained above the table. |
SB safety shoes
SB is the basis of EN ISO 20345. Alongside the protective toe cap, there are requirements for materials and ergonomic properties, among other things. SB alone does not require a closed heel, antistatic properties or penetration resistance.
The standard test does not guarantee that a shoe will be comfortable on every foot. Fit remains a separate choice.
Properties of SB safety shoes
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
S1 safety shoes
S1 adds a closed heel, antistatic properties and heel energy absorption to the basic requirements. Water resistance of the upper material and penetration resistance are not included as standard in S1.
The difference from S1P is therefore not in the protective toe cap, but in protection against sharp objects underfoot.
Properties of S1 safety shoes
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- Closed heel
- Antistatic properties (A)
- Heel energy absorption (E)
S1P safety shoes
S1P is S1 with a metallic penetration-resistant insert. For non-metallic inserts, the 2022 version uses S1PL or S1PS. These variants are tested with different test nails; their meaning is explained below the table.
This combination provides penetration resistance without requiring WPA water resistance. That is a functional difference, not a blanket recommendation for an entire profession.
Properties of S1P safety shoes
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- Closed heel
- Antistatic properties (A)
- Heel energy absorption (E)
- Penetration-resistant metallic insert (P)
S2 safety shoes
S2 is S1 with resistance to water penetration and water absorption of the upper material: WPA. This concerns the material on the outside of the shoe, not the watertightness of the entire construction.
S2 does not require a penetration-resistant insert. Where there are sharp objects on the ground, this is an important difference from S3.
Properties of S2 safety shoes
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- Closed heel
- Antistatic properties (A)
- Heel energy absorption (E)
- Water penetration and absorption of the upper material (WPA)
S3 safety shoes
S3 combines S2 with a metallic penetration-resistant insert and a cleated outsole. S3L and S3S have non-metallic inserts. Protection against water in the upper material remains WPA; water resistance of the whole shoe is a separate property.
S3 does not automatically mean protection against electricity, chemicals or hot surfaces. Such risks require other or additional properties.
Properties of S3 safety shoes
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- Closed heel
- Antistatic properties (A)
- Heel energy absorption (E)
- Water penetration and absorption of the upper material (WPA)
- Penetration-resistant metallic insert (P)
- Cleated outsole
S4 safety boots
S4 is a category for all-rubber or all-polymeric safety footwear, including boots. Familiar examples of polymers are PU (polyurethane) and PVC (polyvinyl chloride). They meet the basic requirements and have antistatic properties and heel energy absorption. For typical boot constructions, a closed heel and a leak-tightness test also apply.
For wet work, the closed rubber or polymeric construction is relevant. S4 does not indicate penetration resistance and does not guarantee against water entering through the opening or where damage occurs.
Properties of S4 safety boots
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- All-rubber or all-polymeric construction
- Closed heel for typical boot design**
- Antistatic properties (A)
- Heel energy absorption (E)
- Leak-tightness test for the boot construction**
S5 safety boots
S5 builds on the rubber or polymeric construction of S4, such as PU or PVC, and adds a metallic penetration-resistant insert and a cleated outsole. S5L and S5S are the variants with non-metallic inserts.
This category therefore combines rubber or polymeric construction with tested resistance to sharp objects underfoot.
Properties of S5 safety boots
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- All-rubber or all-polymeric construction
- Closed heel for typical boot design**
- Antistatic properties (A)
- Heel energy absorption (E)
- Leak-tightness test for the boot construction**
- Penetration-resistant metallic insert (P)
- Cleated outsole
S6 safety shoes
S6 combines S2 with WR: water resistance of the shoe in its assembled state. This is a different test from WPA, which only concerns the upper material.
S6 does not require penetration resistance. The WR test also does not provide a general guarantee of a fixed number of minutes working dry in water.
Properties of S6 safety shoes
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- Closed heel
- Antistatic properties (A)
- Heel energy absorption (E)
- Water penetration and absorption of the upper material (WPA)
- Water resistance of the whole shoe (WR)
S7 safety shoes
S7 combines S3 with WR. You therefore get a cleated outsole, penetration resistance and water resistance of the whole shoe. The variants are called S7L and S7S when the insert is non-metallic.
S7 is not a universally highest or best class: cold insulation and resistance to hot contact, for example, remain separate properties. This combination addresses different risks from those of a dry workplace surface alone.
Properties of S7 safety shoes
- Protective toe cap: 200 J impact and 15 kN compression
- Basic requirements for materials and ergonomic properties
- Slip resistance according to the basic test*
- Closed heel
- Antistatic properties (A)
- Heel energy absorption (E)
- Water penetration and absorption of the upper material (WPA)
- Penetration-resistant metallic insert (P)
- Cleated outsole
- Water resistance of the whole shoe (WR)
What are ESD safety shoes?
ESD means electrostatic discharge. ESD footwear helps dissipate charge through a suitable floor, reducing the risk of damage to sensitive electronics. Antistatic shoes also dissipate charge; the difference lies in the requirements and test method, not in “conductive or non-conductive”. An antistatic shoe therefore does not automatically meet ESD requirements.
Which standards apply to ESD shoes?
- EN IEC 61340-4-3 describes how the electrical resistance of the footwear itself is tested.
- EN IEC 61340-4-5 tests the combination of person, footwear and floor. The result applies to that tested combination.
- EN IEC 61340-5-1 describes the requirements for an ESD control programme to protect electronics in the workplace.
A footwear test and an assessment of the entire ESD workplace therefore have different purposes. These ESD standards do not replace the safety class of the shoe.
When should you wear ESD shoes?
In an ESD workplace, the person, footwear and floor together form the dissipation system. An insulating floor can interrupt this function. The ESD function is intended to protect sensitive products and is not electrical insulation for live working.
In a potentially explosive environment, preventing ignition sparks is a separate safety issue. Suitable antistatic shoes and clothing can form part of the measures. An ESD logo alone does not prove that the complete equipment and workplace are suitable for this purpose.
Fastening and comfort technologies
What is Gore-Tex®?
GORE-TEX footwear combines a waterproof construction with breathability: it keeps water out while allowing water vapour to escape. Gore tests these properties for long-lasting performance. This does not mean your feet will stay dry in all circumstances, for example if water enters through the shoe opening. Care and the condition of the shoe remain important.
View our safety shoes with GORE-TEX.
What is the BOA® Fit System?
The BOA Fit System allows precise adjustment of the fastening using a dial. Many versions tighten by turning the dial and release quickly by pulling the dial out. There are also systems that loosen by turning. Operation therefore depends on the BOA system fitted; pulling is not a universal instruction for every version.
View our safety shoes with BOA or dial fastening.