Dry indoor work
Start with the S1 family for a closed heel, anti-static properties and heel energy absorption.
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Safety ratings, clearly explained.
Understand the markings on professional safety footwear and quickly compare toe, penetration, water and slip protection.
Guide to EN ISO 20345:2022 safety footwear markings
HOW TO READ A RATING
S3SFOSR
S3S
S3 protection with a non-metal penetration insert tested using a 3 mm nail
FO
Outsole resistance to fuel oil
SR
Optional additional slip-resistance test
START WITH THE HAZARD
Which protection should you look for?
These are useful starting points, not substitutes for a workplace risk assessment.
Sharp objects underfoot
Choose a rating with P, PL or PS penetration resistance, matched to the risk identified.
PPLPS
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Wet outdoor conditions
S2 and S3 families resist water penetration through the upper. S3 also adds penetration protection and a cleated outsole.
S2S3S3LS3S
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Whole-footwear waterproofing
Look for WR and the S6 or S7 family when the complete footwear—not only its upper—must resist water.
WRS6S7S7LS7S
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THE MAIN CLASSES
EN ISO 20345:2022 ratings explained
Every EN ISO 20345 safety shoe includes a protective toe cap tested for 200-joule impact protection.
| Rating | What it includes | Useful starting point |
|---|---|---|
| SB | Basic requirements including a 200 J protective toe cap. | Where toe protection is the principal identified requirement. |
| S1 | SB + closed heel, anti-static properties and heel energy absorption. | Dry indoor workplaces, logistics and light industrial use. |
| S1P / PL / PS | S1 + penetration-resistant insert: metal P, non-metal PL or non-metal PS. | Dry environments with a penetration hazard underfoot. |
| S2 | S1 + water penetration and absorption resistance of the upper (WPA). | Damp conditions without a specified penetration-resistant insert. |
| S3 / S3L / S3S | S2 + penetration resistance and a cleated outsole. The suffix identifies the insert test. | Construction, engineering and mixed indoor/outdoor work. |
| S4 | Class II all-rubber or all-polymeric footwear with anti-static properties and heel energy absorption. | Wet, washdown or hygiene-led environments where moulded footwear is suitable. |
| S5 / S5L / S5S | S4 + penetration resistance and a cleated outsole. | Wet environments that also present a penetration hazard. |
| S6 | S2 + water resistance of the whole footwear (WR). | Prolonged wet-weather work without a specified penetration insert. |
| S7 / S7L / S7S | S3-family protection + water resistance of the whole footwear (WR). | Demanding outdoor work combining wet conditions and penetration hazards. |
Some correctly certified footwear may still carry EN ISO 20345:2011 markings while its certificate remains valid. Always use the marking shown on the individual product and footwear label.
MIDSOLE PROTECTION
P, PL and PS are not the same
The letters identify the material and test nail used for the penetration-resistant insert.
P
METALLIC INSERT
Metal penetration resistance
Tested using a 4.5 mm nail. Commonly a steel midsole.
PL
NON-METALLIC INSERT
Large test nail
Non-metal insert tested using a 4.5 mm nail.
PS
NON-METALLIC INSERT
Small test nail
Non-metal insert tested using a smaller 3.0 mm nail.
OPTIONAL MARKINGS
Additional protection codes
These markings sit alongside the main class and show separately tested properties.
AAnti-static footwear
ANAnkle protection
CPartially conductive footwear
CICold insulation
CRCut-resistant upper
EHeel energy absorption
FOOutsole resistance to fuel oil
HIHeat insulation
HROOutsole resistance to hot contact
LGLadder grip
MMetatarsal protection
SCScuff-cap abrasion resistance
SRAdditional slip-resistance test
WPAWater penetration and absorption of upper
WRWater resistance of whole footwear
GRIP AND FLOOR CONDITIONS
Understanding slip-resistance markings
Oil resistance describes sole durability—it does not automatically mean the footwear is slip resistant.
SR
EN ISO 20345:2022
A basic ceramic-tile slip test is part of the standard. SR shows the footwear has also passed the optional additional slip test.
SRASRBSRC
EN ISO 20345:2011
SRA and SRB identify two older test conditions; SRC means both were met. These codes can still appear on valid older-certified products.
Choose for the real surface—not the label alone
Floor material, water, oil, chemicals, loose debris and tread wear all affect grip. HSE recommends considering the actual surfaces and contaminants and, where appropriate, trialling footwear in the workplace.
NEED HELP CHOOSING?
Match the footwear to the job
Tell us the environment, surface conditions and required rating. We’ll help you narrow down the suitable options.
Important information
This guide explains commonly used markings and is not a product specification or workplace risk assessment. Always check the declaration, label and product information for the exact footwear being purchased. Employers should select PPE from a suitable and sufficient risk assessment.
Further guidance: HSE: choosing the right PPE and HSE: slip-resistant footwear.