Foot protection standards guide: what do S1, S3, SR and WR mean?

The short codes on the tongue or label of a safety shoe summarise the tests it has passed. Read them in order: first the main standard, then the safety class (SB, S1, S3 and so on), and finally the additional codes. The diagrams above follow EN ISO 20345:2022 and its sister standards in that order.

How to read the diagrams

• Label example: in the marking S3S · SR · HRO, the first code gives the safety class and the type of penetration-resistant insert; the codes after it show extras such as slip resistance and an outsole that resists hot contact.
• Three standards: shoes whose toecap withstands a 200 J impact fall under EN ISO 20345, those rated for 100 J under EN ISO 20346. Occupational shoes without a toecap fall under EN ISO 20347. The letter S, P or O in the class name shows this split.
• Class table: from SB to S7, each class adds properties to the previous one. S6 and S7 were added in the 2022 edition; S7 is S3 with water resistance of the whole shoe (WR) added.
• Penetration-resistant insert: P stands for a metal insert, PL and PS for non-metal inserts. PS is tested with a thinner nail (3.0 mm). The last letter in names such as S3L and S3S gives this type; with no letter, the insert is metal.
• Slip resistance: the basic slip test is now mandatory for every shoe and is not marked separately. SR shows that the shoe also passed the additional test on a glycerine-covered floor. The old SRA, SRB and SRC codes were removed in the 2022 edition.
• Additional codes: codes such as FO, WPA, WR, HRO, HI, CI, M, AN and CR show extra protection against a specific risk.

Short selection checklist

1. In the risk assessment, list the risks to the feet: impact, crushing, puncture, slipping, water and temperature.
2. If toe protection is needed, choose a model certified to EN ISO 20345 and set the safety class according to these risks.
3. If there is a risk from nails or sharp parts, choose a class with a penetration-resistant insert (S1P, S3, S5, S7) and check the insert type.
4. On wet or oily floors, look for the SR marking; for very cold or hot environments check for CI and HI, and for water look for WR.
5. For live electrical work a safety shoe is not enough; you need insulating footwear certified to EN 50321-1.

This guide is for general information. For exact requirements and test methods, the current text of the standard and the product's instructions for use apply.