Looking for new safety shoes, but not quite sure about the difference between S1, S1P, S2 and S3 — or what S7, SR or S1PL mean? In this article we explain the ratings for safety footwear under the current standard EN ISO 20345:2022 briefly and clearly, including the main differences from the previous 2011 version.
What is EN ISO 20345?
EN ISO 20345 is the European standard for safety footwear. Every safety shoe has a protective toe cap that must withstand an impact energy of 200 joules (comparable to 20 kg falling from a height of about one metre) and a static compression of 15 kN. In addition, every shoe must meet basic requirements, including a slip resistance test on a ceramic tile with a soap solution. On top of this baseline there are protection classes, labelled SB and S1 to S7. The current version is EN ISO 20345:2022, which replaces EN ISO 20345:2011.
The material also determines which classes are possible: S1, S2, S3, S6 and S7 apply to shoes made of leather and other materials, S4 and S5 to footwear made entirely of rubber or polymer, such as many safety boots.
The safety classes at a glance
SB
The basic class: a safety toe cap (200 J) and the basic requirements of the standard, such as basic slip resistance. An open heel area is permitted. In practice, SB is mainly found on special shoes and boots.
S1
SB plus a closed heel area, antistatic properties and energy absorption in the heel area. Suitable for dry working environments such as workshops and warehouses. Note: since the 2022 version, an oil- and fuel-resistant outsole is no longer a standard requirement. If you need it, check whether the shoe carries the FO marking.
S1P, S1PL and S1PS
Everything from S1, plus a puncture-resistant midsole against sharp objects on the ground. Since 2022, the code tells you which type of midsole is in the shoe: P is a metal midsole (tested with a 4.5 mm nail), PL a non-metal midsole tested with the same 4.5 mm nail, and PS a non-metal midsole tested with a thinner 3 mm nail. A popular choice for construction and industry. View our S1P safety shoes.
S2
Everything from S1, with an upper that resists water penetration and water absorption (WPA). That means water-repellent, not fully waterproof. Ideal for work in damp conditions.
S3, S3L and S3S
Everything from S2, plus a puncture-resistant midsole (P, PL or PS, labelled S3, S3L or S3S) and a cleated outsole for extra grip. The most popular class in construction and heavy industry. View our S3 safety shoes.
S4 and S5
Classes for footwear made entirely of rubber or polymer, such as safety boots. S4 has a closed heel area, antistatic properties and energy absorption in the heel; S5 adds a puncture-resistant midsole and a cleated outsole. Ideal for wet and dirty environments, such as agriculture, groundwork and the food industry. View our safety boots.
S6 and S7 (new)
New in the 2022 version. S6 is S2 plus water resistance of the whole shoe (WR), S7 is S3 plus WR. These shoes often have a waterproof membrane and are intended for people who work in wet conditions all day.
Additional markings on your safety shoe
In addition to the class, a safety shoe can carry extra markings for specific risks. The most important:
- SR: additional slip resistance, tested on a ceramic tile with glycerine (a slippery, oily substance).
- FO: outsole resistant to oil and fuel (optional since 2022).
- LG: ladder grip, a sole profile that provides grip on ladders.
- SC: abrasion-resistant scuff cap, useful for a lot of kneeling work.
- WR: water resistance of the whole shoe.
- HRO: outsole resistant to hot contact; HI and CI: insulation against heat and cold.
- M: metatarsal protection; AN: ankle protection; CR: cut-resistant upper.
What has changed compared to EN ISO 20345:2011?
- Slip resistance: the old SRA, SRB and SRC markings have disappeared. The test on a ceramic tile with soap solution is now a basic requirement for every safety shoe; the additional test with glycerine earns the SR marking.
- Oil and fuel resistance is no longer a standard requirement for S1 to S5, but an optional marking (FO).
- Puncture resistance: in 2011, P stood for any puncture-resistant midsole. Now P only stands for metal, and PL and PS are the non-metal variants.
- Water resistance of the upper is now called WPA (previously WRU).
- New classes S6 and S7 for shoes that are water-resistant as a whole, and new markings such as LG and SC.
- Transition: new certifications follow the 2022 version. A certificate to the 2011 version remains valid until it expires (an EU type-examination certificate is valid for a maximum of five years). That is why you will still come across both designations in practice.
Which class do you need?
The right class depends on your work environment and the risks you are exposed to: think of falling objects, sharp objects on the ground, moisture, slippery floors or chemicals. In doubt? Contact us; we are happy to advise you on which safety shoe suits your work.
Curious about our full range? View our safety shoes, or read more background information on our all about safety shoes page.
Frequently asked questions about safety shoe ratings
What is the difference between S1P and S3?
Both have a puncture-resistant midsole. An S3 shoe also has a water-repellent upper (WPA) and a cleated outsole. S1P is therefore mainly suitable for dry conditions, while S3 also suits damp environments and outdoor work.
Is an S3 safety shoe waterproof?
Not completely. The upper of an S3 shoe resists water penetration and absorption, but the shoe as a whole has not been tested for water resistance. If you need a waterproof shoe, choose S7 (for shoes certified to the 2011 version: S3 with the WR marking), or a rubber or polymer boot in class S5.
Can I still use safety shoes certified to EN ISO 20345:2011?
Yes. Shoes with a valid certificate to the 2011 version may still be sold and worn; the certificate remains valid until its expiry date. New models are certified to the 2022 version.
What is the difference between antistatic and ESD?
Under EN ISO 20345, antistatic safety shoes (from S1 upwards) have an electrical resistance between 100 kΩ and 1000 MΩ. ESD safety shoes have a narrower range of 100 kΩ to 100 MΩ: the upper limit comes from EN 61340-5-1, the lower limit from EN ISO 20345. This protects sensitive electronics against discharge. So every ESD shoe is antistatic, but not every antistatic shoe is ESD. View our ESD safety shoes.