European Standard · Foot Protection
EN ISO 20345 – Safety Footwear: The Complete Guide to the European Standard for Protective Footwear
EN ISO 20345 is the European and international standard specifying basic and additional requirements for safety footwear with protective toe caps, designed to protect workers from impact, compression, slips and other foot hazards in industrial and construction environments. This guide explains the classification system, marking codes, testing requirements and how to choose the right safety boots or shoes for your job.
1. Scope
EN ISO 20345 applies to safety footwear fitted with a protective toe cap rated to withstand at least 200 joules of impact energy and 15 kN of compression. It defines a base classification system (SB, S1–S5) built from a common set of basic requirements, plus additional optional markings for specific hazards such as chemical resistance, heat resistance and metatarsal protection.
2. Exclusions & Related Standards
- Footwear without a protective toe cap falls under EN ISO 20347 (occupational footwear), not EN ISO 20345.
- Does not cover hand protection – see EN 388 protective gloves.
- Does not cover head protection – see EN 397 industrial safety helmets.
- Electrically insulating footwear for live electrical work may require additional certification beyond the base standard.
- Does not cover fall protection equipment – see EN 361 full body harnesses.
3. Classification System (SB, S1–S5)
| SB | Basic requirement: toe cap protection against 200 J impact and 15 kN compression |
| S1 | SB + closed heel area, antistatic properties, energy absorption of the seat region |
| S1P | S1 + penetration-resistant midsole |
| S2 | S1 + water penetration and absorption resistance of the upper |
| S3 | S2 + penetration-resistant midsole and cleated outsole |
| S4 / S5 | Equivalent protection levels to S1/S3 for all-rubber or all-polymer boots |
4. Requirements and Testing
- Toe cap impact resistance (200 J) and compression resistance (15 kN)
- Slip resistance testing on ceramic tile with glycerine and steel floor with detergent
- Antistatic or electrically insulating properties depending on marking
- Energy absorption of the heel region to reduce impact fatigue
- Optional penetration resistance, water resistance and thermal insulation testing
5. Selecting the Right Safety Footwear
Choosing the right classification depends on the work environment: dry indoor sites often suit S1 or S1P footwear, wet or outdoor sites benefit from the water-resistant upper of S2 or S3, and sites with sharp debris on the ground should specify a penetration-resistant midsole (P). Additional markings like HRO (heat resistant outsole), CI (cold insulation) or M (metatarsal protection) should be matched to specific site hazards.
6. Inspection, Care and Maintenance
- Check the outsole tread depth and toe cap integrity regularly for wear
- Clean and dry footwear properly to preserve waterproofing and antistatic performance
- Replace footwear once the sole loses adequate slip resistance or the upper is damaged
- Store away from direct heat sources that could degrade rubber compounds
- Follow manufacturer guidance on maximum service life for insulating or antistatic properties
7. Product Examples
- S1P ankle boots for warehouse and light industrial use
- S3 waterproof boots with penetration-resistant midsole for construction
- S5 all-rubber boots for wet or muddy outdoor sites
- Metatarsal-protected boots for heavy object handling
- Heat-resistant outsole boots for foundry and roofing work
8. Standard Information
- Status: Active international standard (EN ISO 20345)
- ICS code: 13.340.50
- Committee: CEN/TC 161 & ISO/TC 94
- Related standards: EN 388, EN 397, EN 361
- See the full EN Standards Library for all safety equipment standards
Frequently Asked Questions about EN ISO 20345
What does the EN ISO 20345 standard cover?
EN ISO 20345 specifies requirements, testing and marking for safety footwear with protective toe caps used to guard against impact, compression, slips and other workplace foot hazards.
What is the difference between S1, S2 and S3 safety boots?
S1 provides basic protection with antistatic properties and a closed heel, S2 adds water-resistant upper protection, and S3 adds a penetration-resistant midsole and cleated outsole for tougher outdoor environments.
What does SB mean on safety footwear?
SB is the base classification confirming the footwear meets the minimum toe cap impact and compression requirements without any additional optional features.
Is EN ISO 20345 the same as EN ISO 20347?
No, EN ISO 20345 covers footwear with a protective toe cap, while EN ISO 20347 covers occupational footwear without toe cap protection.
How do I know if safety boots are penetration resistant?
Look for the letter P in the classification code (such as S1P or S3), which indicates a penetration-resistant midsole has been tested and certified.
How often should safety footwear be replaced?
Footwear should be replaced when the outsole tread wears down, the toe cap or midsole is damaged, or according to the manufacturer's recommended service life for antistatic or insulating properties.
What does metatarsal protection mean?
Metatarsal protection (marked M) extends impact protection across the top of the foot, guarding against injuries from falling or rolling heavy objects.