EN ISO 20345 : 2022
Safety Footwear Guide
Your complete reference for understanding European safety footwear standards, classes, and protection markings.
S-Class — Safety Footwear
S-classes are cumulative — each class includes all features of the previous class.
Basic requirement — 200 J toe cap, slip-resistant outsole (SRA or SRB). Mandatory base for all S-class shoes.
SB + anti-static (ESD), energy-absorbing heel zone, oil-resistant outsole. Closed heel design.
S1 + penetration-resistant midsole (1100 N nail protection). Most common class in manufacturing.
S1P in low-cut (ankle-height) design — lightweight and flexible for indoor or light-duty work.
S1 + water-resistant upper material. Protects against splashing liquids, not full immersion.
S2 + penetration-resistant midsole (1100 N) + cleated outsole for outdoor grip. The most versatile class.
S3 protection in a low-cut (ankle-height) shoe — combines outdoor toughness with lightweight freedom.
All-rubber or all-polymer boot with S1 base properties. Fully waterproof for wet environments.
S4 + penetration-resistant midsole (1100 N) + cleated outsole. Highest rubber boot class.
S3 + fully waterproof (WR) breathable membrane throughout the shoe. Highest overall safety class.
O-Class — Occupational Footwear (No Steel Toe)
O-class footwear is designed for environments with low impact risk but other protection requirements.
Occupational shoe: anti-static, energy-absorbing heel, oil-resistant sole — NO steel toe cap.
O1 + water-resistant upper material.
O2 + penetration-resistant midsole (1100 N) + cleated outsole.
Additional Protection Markings
These letters are appended to the safety class to indicate additional protections the shoe provides (e.g. S3 SRC ESD AN).
Anti-static (10⁶–10⁸ Ω)
Energy absorption in heel (≥ 20 J)
Penetration resistance (midsole, 1100 N)
Whole shoe water resistant (upper + sole seam)
Water-resistant upper only (not sole seam)
Ankle protection — lateral malleolus zone padded
Heat insulation of sole assembly (300 °C contact, 1 min)
Cold insulation of sole assembly (−17 °C)
Electrostatic dissipation per EN 61340-4-3 (< 10⁸ Ω)
Slip resistant on ceramic tile + sodium lauryl sulphate
Slip resistant on steel floor + glycerol
SRA + SRB combined — highest slip resistance class
Cut resistance of upper material (EN 388)
Heat resistant outsole (300 °C contact, 1 min)
Fuel oil resistant outsole
Metatarsal protection (upper foot)
How to Read a Marking
Let's decode a real HKS shoe label together:
Water-resistant upper + penetration resistance + cleated sole (S2 + P + outsole)
Highest slip resistance on both ceramic and steel floors
Electrostatic dissipation — for sensitive electronics environments
Ankle protection padding
Full waterproofing throughout the shoe
Toe Cap Materials
All S and O class shoes meeting EN ISO 20345 include a toe cap tested to 200 J energy absorption.
Steel
✓ Highest protection, low cost
✗ Heavier, triggers metal detectors
Aluminium / Composite
✓ 50% lighter than steel, metal-detector friendly
✗ Slightly wider profile than steel
Plastic / Fibreglass
✓ Fully metal-free, lightest option, thermal in cold
✗ Can wear over prolonged use
Not sure which safety class is right for you? Our experts will help you choose.