Shoes
Safety Footwear Explained: S1, S2, S3, S4, S5, S6, S7 and ESD
Which protection class do you actually need? All markings from S1 to S7 explained in plain language – up to date with EN ISO 20345:2022, including the older SRA, SRB, SRC and WRU codes you will still encounter.
Safety footwear is a core part of personal protective equipment (PPE) at work. And for good reason: figures published by the German Social Accident Insurance (DGUV) show that the foot and ankle area is affected in roughly 17.5 per cent of all occupational accidents in trade and industry. That makes feet the second most frequently injured part of the body.
But which safety shoe is the right one? Between S1P, S3, ESD and SRC it is easy to lose track – and since the EN ISO 20345:2022 revision, some of these codes have changed as well. This guide covers both: the current marking system and the older one you will still come across in the market.
What EN ISO 20345:2022 changed
EN ISO 20345:2022 has applied since 30 June 2022 and replaces the 2011 edition. One point matters most in practice: both marking systems are currently in circulation. Footwear certified under the previous edition may still be placed on the market until its certificate expires – certificates run for a maximum of five years. So you will keep finding models marked "SRC" next to models marked "SR" for some time. That is neither a contradiction nor a defect.
These are the four changes that matter day to day:
| Topic | Until 2011 | Since 2022 |
|---|---|---|
| Slip resistance | Additional marking SRA, SRB or SRC | A basic level of slip resistance is now mandatory for every safety shoe and is no longer marked separately. Only the additional, stricter test on a ceramic tile with glycerol leads to the SR marking. SRA, SRB and SRC have been dropped. |
| Penetration resistance | A single code, P | Split into P (metal insert), PL (non-metallic, tested with a 4.5 mm nail) and PS (non-metallic, tested with a 3.0 mm nail). PS offers finer protection against thin objects. |
| Water protection | WRU for the upper | WPA replaces WRU (water penetration and absorption of the upper). WR still stands for a waterproof complete shoe. |
| New classes | S1 to S5 | Additionally S6 (S2 with a waterproof complete shoe) and S7 (S3 with a waterproof complete shoe). |
Two further markings are new: SC for an abrasion-resistant toe cap covering and LG for ladder grip. And one detail that is easily missed: fuel resistance of the outsole (FO) is no longer a basic requirement of classes S1 to S3 but an optional additional marking. If you need it, you now have to look for it specifically.
Hazards and selection criteria
In Germany, requirements for employees' foot protection are set out in occupational health and safety legislation and accident prevention regulations. Depending on the type of work, the employer must carry out a risk assessment. It may cover the following points, among others:
| Hazard | Cause and type of exposure | Selection criterion |
|---|---|---|
| Mechanical impact | Falling objects or crushing of the forefoot | Strength of the shoe in the toe area (toe cap) |
| Falls and impact on the heel | Energy absorption of the heel area, reinforced heel counter | |
| Impact on ankle and metatarsus | Effective equipment, e.g. padding, ankle or metatarsal protection | |
| Stepping on sharp or pointed objects | Penetration resistance of the sole (P, PL or PS) | |
| Slipping | Smooth, wet or greasy floors | Slip resistance of the sole (basic requirement, optionally SR) |
| Electricity | Electrical voltage | Insulation or dissipation of voltage (A, C) |
| Thermal exposure | Heat or cold | Heat or cold insulation, heat resistance (HI, CI, HRO) |
| Chemical exposure | Liquids, dusts or mists | Tightness, resistance |
| Biological exposure | Micro-organisms or other biological substances | Liquid-tight, easy to clean and disinfect |
| Ignition of explosive atmospheres | Static electricity | Dissipative properties |
Protection classes S1 to S7 under EN ISO 20345:2022
Once the legally required, task-specific risk assessment has been carried out, the shoe can be selected. Safety footwear falls under EN ISO 20345 (code S, with a toe cap), occupational footwear without a toe cap under EN ISO 20347 (code O). The protection classes build on one another:
| Class | Requirements |
|---|---|
| SB | Basic requirement: toe cap (200 joules impact energy) and basic slip resistance |
| S1 | SB + closed heel area + antistatic (A) + energy absorption in the heel area (E) |
| S1P | S1 + penetration resistance with a metal insert |
| S1PL | S1 + non-metallic penetration resistance (tested with a 4.5 mm nail) |
| S1PS | S1 + non-metallic penetration resistance (tested with a 3.0 mm nail) |
| S2 | S1 + water penetration and absorption of the upper (WPA) |
| S3 | S2 + penetration resistance (metal) + cleated outsole |
| S3L / S3S | As S3, with non-metallic penetration resistance (PL or PS) |
| S4 | Fully moulded rubber or polymer footwear + antistatic + energy absorption in the heel area + closed heel area |
| S5 | S4 + penetration resistance + cleated outsole (non-metallic variants: S5L / S5S) |
| S6 (new) | S2 + waterproof complete shoe (WR) |
| S7 (new) | S3 + waterproof complete shoe (WR) – non-metallic variants: S7L / S7S |
Note: fuel resistance of the outsole (FO) was part of S1 to S3 until 2011 and is now an optional additional marking.
Please note: This overview is intended as initial guidance. We accept no liability for its completeness or accuracy – only the current official text of EN ISO 20345 in its applicable edition is authoritative. This overview does not replace the legally required risk assessment.
Additional markings
Beyond the protection class, a shoe may carry further properties. These codes appear directly after the class designation, for example "S3 SR CI".
| Code | Meaning |
|---|---|
| P | Penetration resistance, metal insert |
| PL | Penetration resistance, non-metallic, tested with a 4.5 mm nail |
| PS | Penetration resistance, non-metallic, tested with a 3.0 mm nail |
| SR | Enhanced slip resistance (ceramic tile with glycerol). Every safety shoe meets the basic level of slip resistance, which is not marked. |
| A | Antistatic footwear |
| C | Conductive footwear |
| E | Energy absorption in the heel area |
| WPA | Water penetration and absorption of the upper (replaces WRU) |
| WR | Waterproof complete shoe |
| SC (new) | Abrasion resistance of the toe cap covering (scuff cap) |
| LG (new) | Ladder grip |
| CI | Cold insulation |
| HI | Heat insulation |
| HRO | Resistance to contact heat |
| FO | Fuel resistance of the outsole (optional since 2022) |
| M | Metatarsal protection |
| AN | Ankle protection |
| CR | Cut resistance of the upper |
Discontinued: SRA, SRB, SRC and WRU. You will still find them on footwear whose certificate under the 2011 edition is still valid.
ESD-certified safety footwear
Electrical properties are among the requirements EN ISO 20345 places on safety footwear. Shoes are divided into three ranges based on their electrical resistance: conductive, antistatic and insulating. The aim is not only to protect people, but also components, machinery and tools.
This is where IEC/EN 61340-5-1 comes in, which deals with electrostatic discharge (ESD) and the protection of electronic devices from electrostatic phenomena. The electrical resistance of the footwear must be between 100 kilohms and 35 megohms to carry the yellow ESD marking.
An important distinction: antistatic (A) and ESD are not the same thing. An antistatic safety shoe to EN ISO 20345 covers a considerably wider resistance range and primarily protects the wearer. Anyone manufacturing or handling electronic components needs explicit ESD certification to IEC/EN 61340-5-1 – the "A" marking alone is not sufficient.
Which safety shoe is right for me?
The legally required risk assessment cannot be substituted – but we can offer some rough guidance:
- S1 suits work areas where no exposure to moisture is expected, primarily indoors.
- S1P, S1PL and S1PS cover the S1 range and add a penetration-resistant sole, reducing the risk from sharp and pointed objects such as screws or broken glass. For very fine objects, the PS variant is the stricter test.
- S2 is used where, in addition to the protection offered by S1, wet conditions are expected.
- S3 is the classic choice for foot protection, for example in construction: protection against mechanical impact, against moisture, and with a penetration-resistant insert.
- S4 and S5 are fully moulded rubber or polymer boots for permanently wet and dirty environments – agriculture, food processing or civil engineering, for instance.
- S6 and S7 are the right choice when the complete shoe has to be waterproof without being a boot: S6 based on S2, S7 based on S3. Typical for outdoor trades in sustained rain, roofers or winter road maintenance.
Drawing on years of accident data from industry and trade, the DGUV has published a collection of examples that provides orientation when selecting foot protection – it does not replace the legally required risk assessment.
Safety footwear from inba arbeitsschutz
Our range covers safety and occupational footwear for all sectors, for women and men – from the classic safety shoe with a toe cap to boots for the most demanding conditions. When selecting our range we pay particular attention to high quality standards and wearing comfort, premium materials and first-class leather. Hardly any other part of the body is at such risk as your feet – and no other pair of shoes you own is put under as much strain as your work footwear.
Not sure which class suits your working environment? Give us a call or send us a message – we have been advising businesses in trade, industry, healthcare and hospitality for more than 30 years.
Last updated: August 2026. All information provided without warranty as to completeness or accuracy; the applicable official standard text is authoritative.