If you've compared two safety shoes lately and noticed one is marked "S1P SRC" and another "S1PL FO SR," you've run into the shift from the old EN ISO 20345:2011 standard to the current 2022 version. The markings changed, the tests changed, and a few new categories appeared. Here's a clear, practical breakdown of what actually changed, and what it means when you're choosing a pair.
EN ISO 20345:2022 (updated by A1:2024) replaced the 2011 standard, mainly to modernise the tests and remove ambiguity. The three biggest changes: slip resistance became a basic requirement for nearly all footwear (so SRA/SRB/SRC markings were retired and a new optional SR mark appeared); non-metallic puncture protection was split into two grades, PS and PL, based on the test-nail size; and the water-resistance marking WRU became WPA, with new S6 and S7 classes added for genuinely water-resistant whole shoes. Footwear certified to the 2011 standard remains valid and safe to wear during the transition — it's just tested to the previous method.
Withdrawal date Nov 2024
+ A1:2024 amendment
Why did the standard change at all?
EN ISO 20345 sets the requirements for safety footwear across Europe — the toe cap, the slip resistance, the puncture protection, and everything that goes into that little block of letters on the label. The 2011 edition served for over a decade, but materials and manufacturing moved on. Composite and textile components became common, and the old test methods didn't always describe them well.
The 2022 update (later refined by the A1:2024 amendment) was written to bring the test methods up to date, reflect modern non-metallic materials, and remove ambiguity from labelling, so that what's printed on a shoe more accurately describes what it was tested to do. If you want the fundamentals of how the whole system works, our guide to EN ISO 20345 explained covers the basics in plain English.
Change 1: Slip resistance is now a basic requirement
This is the change you'll notice most often, because it affects almost every shoe on the market. Under the 2011 standard, slip resistance was an add-on marked SRA, SRB or SRC. Under 2022, basic slip resistance is built into the standard itself, so those old letter codes were retired.
SRA - passed on wet ceramic tile (detergent). SRB - passed on oily steel (glycerol). SRC - passed both tests.
Basic slip resistance is mandatory and carries no letter. An optional extra test adds the mark SR. Untested special footwear is marked Ø.
In practice: a 2011 shoe proudly marked "SRC" and a 2022 shoe marked "SR" are both slip-tested, they've just been assessed under different systems. Neither marking means a shoe is non-slip in every condition, which is why understanding the ratings matters. Our guide to non-slip safety shoes explains how to match slip performance to your floor.
Change 2: Non-metallic puncture protection splits into PS and PL
This is the change behind those unfamiliar "PS" and "PL" letters. Under 2011, every puncture-resistant midsole, metal or non-metal, was simply marked "P," tested with a 4.5mm nail. The problem: a fine, thin nail is harder to stop than a thick one, and non-metallic inserts behave differently from steel plates. The 2022 standard made this clearer.
One mark: P. All midsoles, steel or non-metallic, tested with a single 4.5mm nail.
Steel midsole keeps P. Non-metallic inserts split: PL (4.5mm nail) and PS (thinner 3mm nail, the tougher test).
So a 2022 shoe marked "PS" has a non-metallic midsole proven against the finer, more demanding 3mm nail, while "PL" uses the 4.5mm nail. Both are valid; PS is simply the more stringent non-metallic grade. This matters if your work involves fine, sharp debris. If you're weighing midsole materials, our comparison of Kevlar vs composite midsole breaks down how these non-metallic inserts differ.
| Marking | Standard | Insert type | Test nail |
|---|---|---|---|
| P | 2011 & 2022 | Any (2011) / steel (2022) | 4.5 mm |
| PL | 2022 | Non-metallic | 4.5 mm |
| PS | 2022 | Non-metallic | 3.0 mm (stricter) |
The finer the test nail, the harder the puncture test is to pass, which is why PS represents the higher non-metallic protection grade.
Change 3: Water resistance, WRU becomes WPA, plus new S6 and S7
The old "WRU" (Water Resistant Upper) marking caused genuine confusion, people read it as "waterproof," which it never meant. It only tested the upper material, not the finished shoe, so water could still get in through the seams.
WRU — water-resistant upper material only. WR, whole-shoe water resistance (unchanged).
WPA replaces WRU (water penetration & absorption of the upper). New S6 and S7 classes bundle whole-shoe WR into S2/S3-style packages.
The key takeaway hasn't changed: neither WRU nor WPA means "waterproof." Only a shoe marked WR (or the new S6/S7 classes that include it) has been tested for whole-shoe water resistance. If genuinely wet conditions are part of your job, look for WR or S6/S7, not WPA.
New and clearer protection classes
The 2022 standard didn't just tweak markings, it added categories to make selection clearer, especially around puncture and water resistance.
- S1P variants: you'll now see S1PS and S1PL, the same familiar S1P, with the non-metallic puncture grade spelled out.
- S3 variants: S3S and S3L apply the same PS/PL logic to S3 footwear.
- S6 and S7: new classes that combine whole-shoe water resistance (WR) with the S2 and S3 packages respectively, a clearer signal of a genuinely water-resistant shoe.
- Optional feature marks: additional codes such as SC (scuff-cap abrasion resistance) and FO (fuel-oil resistance, now an optional add-on rather than automatic) appear where tested.
One easy-to-miss detail: under 2011, oil resistance (FO) was part of the basic S1 package. Under 2022, FO became a separate optional marking — so a 2022 shoe only guarantees an oil-resistant outsole if it actually carries the FO mark. Always read the full marking string, not just the class.
Do I need to replace my 2011-certified safety shoes?
No. This is the question that worries people most, and the answer is reassuring: footwear certified to EN ISO 20345:2011 remains valid and safe to wear. A shoe tested under the old standard protects you exactly as it was certified to, the standard changing doesn't make existing footwear unsafe.
There's a transition period, and both old- and new-standard products are on the market together. When you're buying new footwear, the 2022 marking gives you clearer, more up-to-date information. But there's no need to throw out sound 2011-certified shoes.
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2011The previous EN ISO 20345 standard is published and used for over a decade.
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2022The updated standard is published, modernising the test methods and markings.
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2024The A1:2024 amendment refines the 2022 standard; the 2011 reference reaches its withdrawal date in the harmonised list.
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TransitionOld and new certified products coexist on the market while stocks and certifications turn over.
Whichever standard a shoe is certified to, your workplace decides what's acceptable. An employer's PPE policy and risk assessment determine the required protection level and certification for your specific role — that always comes before any marking on the box.
Frequently asked questions
Is EN ISO 20345:2022 footwear safer than 2011 footwear?
Not inherently. The 2022 standard uses updated tests and clearer markings, but a 2011-certified shoe still provides the protection it was tested for. The main benefit of 2022 is more precise information, for example, knowing whether a non-metallic midsole is PS or PL grade.
What's the difference between SRC and SR?
SRC is a 2011 marking meaning a shoe passed both the ceramic (SRA) and oily-steel (SRB) slip tests. Under 2022, basic slip resistance is mandatory and unmarked, while SR is an optional extra slip test. Both indicate slip-tested footwear under different systems.
What do PS and PL mean on a 2022 shoe?
Both mark a non-metallic puncture-resistant midsole. PL is tested with a 4.5mm nail; PS with a thinner, more demanding 3mm nail. PS is the higher non-metallic grade. Steel midsoles keep the original "P" marking.
Does WPA mean the shoe is waterproof?
No. WPA (which replaced WRU) tests only the upper material for water penetration and absorption, not the whole shoe. For genuine whole-shoe water resistance, look for WR, or the new S6 and S7 classes that include it.
Can I still buy and wear 2011-certified safety shoes?
Yes. Certified stock produced under the 2011 standard remains valid and safe to use during the transition period. When buying new, the 2022 marking simply gives clearer, up-to-date test information.
The takeaway
The move from EN ISO 20345:2011 to 2022 wasn't about making old shoes unsafe, it was about making the label tell you more. Slip resistance is now standard, puncture protection is graded more precisely with PS and PL, and water resistance is described more honestly. When you're choosing your next pair, read the full marking string, match it to what your job and your employer actually require, and you'll know exactly what you're getting. For a deeper walk-through of every code, our full EN ISO 20345 guide is the place to go next.
