ISO 20345 provides 6 main classifications (or ratings) for safety footwear.  

• S4 – Footwear with an upper constructed from rubber or polymeric material and a protective toecap 
• S2 – Same specification as the “S1” rating plus a water resistant upper 
• SB – Footwear with a protective toecap 
• S1 – Same specification as the “SB” rating plus an antistatic, fuel resistant and energy absorbent sole and an enclosed heel 
• S3 - Same specification as the “S2” rating plus a protective midsole 
• S5 - Same specification as “S4” with a protective midsole 

Ratings SB, S1, S2 and S3 are for trainers, shoes and boots whereas ratings S4 and S5 are for wellingtons. 

The standard stipulates that all protective toecaps must provide protection for impacts from above of up 200 joules energy in one hit and a squeezing motion to the sides of 100 joules energy.  Midsoles must provide protection for impacts of up to 100 joules energy. 

ISO 20345 doesn’t stop there!!  It also covers the slip resistance of the footwear’s soles and 4 additional features that can be added to the shoe’s specification. 

For slip resistance the footwear sole must confirm to one of the 3 following ratings: 

• SRB – Tested for slip resistance on steel with a glycerol solution 
• SRA – Tested for slip resistance on ceramic tiles with a soapy solution 
• SRC - Tested to both tests for an “SRA” and “SRB” rating 

The additional features that can be added to a specification are as follows: 

• HI – Heat insulative outsole 
• CI – Cold insulative outsole 
• WP – Waterproof lining inside the upper  
• HRO – Heat resistant outsole up to 300 degrees centigrade 

Download our EN ISO 20345 here EN-ISO-20345-Explanation.pdf (739.23 kb)