What S Numbers Mean For Safety Footwear

I wear boots and I prefer steel toe capped boots. Recently I bought my first pair online sight unseen.

While researching my choices, I noticed many pairs of boots advertised an S number. Here is what those S ratings mean:

SB
  • Basic safety
S1
  • Closed seat region
  • Antistatic properties
  • Energy absorption of seat region
S2
  • Closed seat region
  • Antistatic properties
  • Energy absorption of seat region
  • Water penetration and water absorption
S3
  • Closed seat region
  • Antistatic properties
  • Energy absorption of seat region
  • Water penetration and water absorption
  • Penetration resistance
  • Cleated outsole
S4
  • Antistatic properties
  • Energy absorption of seat region
S5
  • Antistatic properties
  • Energy absorption of seat region
  • Penetration resistance
  • Cleated outsole