Safety shoe ratings are category codes under EN ISO 20345, running from SB up to S7. Every code starts from the same base, a toe cap tested to a 200-joule impact, and each higher rating adds a specific tested property on top. This page lists all of them in one table, then explains each code in plain English.
The current standard is EN ISO 20345:2022, published with an amendment as EN ISO 20345:2022+A1:2024. It introduced S6 and S7, retired the old SRA, SRB and SRC slip markings, and split puncture resistance into P, PL and PS.
SB is a toe cap alone. S1 adds a closed heel, antistatic properties and an energy-absorbing heel. S1P adds a puncture-resistant insert. S2 adds upper water resistance. S3 combines both plus a cleated outsole. S4 and S5 are moulded footwear. S6 and S7 add whole-footwear water resistance.
The Complete Safety Shoe Ratings Table, SB to S7
| Rating | Class | What it includes | Typical use |
|---|---|---|---|
| SB | I or II | Basic requirements only: 200 J toe cap. Heel region may be open. | Rarely accepted as workplace PPE on its own |
| S1 | I | SB + closed seat region + antistatic (A) + energy absorption of the seat region (E) | Dry indoor work, no sharp underfoot hazard |
| S1P | I | S1 + penetration resistance, metallic insert (P) | Dry indoor work with nails, staples or swarf |
| S1PL | I | S1 + penetration resistance, non-metallic insert tested at 4.5 mm (PL) | As S1P, lighter and more flexible underfoot |
| S1PS | I | S1 + penetration resistance, non-metallic insert tested at 3 mm (PS) | As S1PL, plus finer sharp objects |
| S2 | I | S1 + water penetration and absorption resistance of the upper (WPA) | Damp indoor work, wash-down edges, kitchens |
| S3 | I | S2 + penetration resistance (P) + cleated outsole | Construction, groundworks, outdoor and mixed sites |
| S3L / S3S | I | As S3, with a non-metallic insert tested at 4.5 mm (L) or 3 mm (S) | As S3, with a lighter insert |
| S4 | II | All-rubber or all-polymeric + closed seat region + antistatic + energy absorption | Food production, agriculture, wash-down |
| S5 | II | S4 + penetration resistance + cleated outsole | Wet, muddy or heavily soiled environments |
| S5L / S5S | II | As S5, with a non-metallic insert (L = 4.5 mm, S = 3 mm) | As S5, with a lighter insert |
| S6 | I | S2 + whole-footwear water resistance (WR) | Prolonged wet work needing a leather or fabric upper |
| S7 | I | S3 + whole-footwear water resistance (WR) | Wet outdoor sites with sharp underfoot hazards |
| S7L / S7S | I | As S7, with a non-metallic insert (L = 4.5 mm, S = 3 mm) | As S7, with a lighter insert |
What Every Certified Safety Shoe Must Do
Every rating from SB upwards requires a toe cap withstanding a 200-joule impact and 15 kN compression, plus slip resistance tested on ceramic tile with a soap solution, material innocuousness, ergonomic performance, and defined durability of the upper and outsole.
These are the basic requirements, and they are what the letter S means. A shoe without them is not safety footwear regardless of how it is described.
- Toe cap: 200 J impact and 15 kN compression. Roughly a 20 kg object falling one metre, and around 1.5 tonnes of slow crushing load.
- Slip resistance: mandatory since the 2022 revision, tested on ceramic tile with a sodium lauryl sulphate solution.
- Construction and materials: tear strength, flexing resistance, interlayer bond strength, and limits on substances such as chromium VI in leather.
- Ergonomics: the footwear must be wearable and functional, not simply protective.
Two related standards are often confused with this one. EN ISO 20347 covers occupational footwear with no toe cap at all, coded OB and O1 to O7. EN ISO 20346 covers protective footwear with a lower 100-joule toe cap, coded PB and P1 to P5. Only EN ISO 20345 gives you the 200-joule toe cap, and only its codes begin with S.
What Each Rating Adds, Step by Step
SB: the baseline
SB means the footwear meets the basic requirements and nothing else. The heel region may be open, there is no antistatic requirement and no puncture protection. Most UK employers do not accept SB alone, because a workplace risk assessment that identifies impact risk usually identifies other risks alongside it.
S1: closed heel, antistatic, energy-absorbing heel
S1 adds three things to SB. A closed seat region, which rules out open-backed constructions. Antistatic properties, meaning electrical resistance between 0.1 MΩ and 1,000 MΩ so static charge drains gradually. And energy absorption of the seat region, at least 20 joules, which cushions heel strike on hard floors.
Note what antistatic is not. It is not electrical insulation and must never be relied on as protection against contact with live equipment.
S1P, S1PL and S1PS: adding puncture protection
The P family adds a penetration-resistant insert between the outsole and the footbed, resisting at least 1,100 N. The suffix tells you which insert and which test point:
| Code | Insert | Test point | Effect |
|---|---|---|---|
| P | Metallic plate | 4.5 mm | Rigid, partial footbed coverage, heavier |
| PL | Non-metallic textile | 4.5 mm | Flexible, near-full coverage, lighter |
| PS | Non-metallic textile | 3 mm | As PL, plus thinner sharp objects |
PS is the stricter of the two non-metallic routes, because a fine 3 mm point is harder for a woven insert to stop than a blunter 4.5 mm one. All three certify the same 1,100 N force. The full picture sits in our complete S1P safety shoes guide.
S2: upper water resistance
S2 takes S1 and adds water penetration and absorption resistance of the upper, marked WPA. This replaced the older WRU marking in the 2022 revision. Importantly, S2 does not include a puncture-resistant insert, so S2 is not simply a step up from S1P. They protect against different things.
S3: the common site specification
S3 combines S2 with penetration resistance and adds a cleated outsole. This is the minimum most UK construction sites specify, because it covers wet ground, sharp debris and uneven terrain in one package. S3L and S3S are the same rating with a non-metallic insert.
S4 and S5: moulded Class II footwear
S4 and S5 apply only to all-rubber or all-polymeric moulded footwear, which in practice means wellingtons and food-industry boots. S4 covers a closed seat region, antistatic properties and energy absorption. S5 adds penetration resistance and a cleated outsole. You will never find an S5 trainer, because the category requires a moulded one-piece construction.
S6 and S7: the new water-resistance categories
These arrived with the 2022 revision and are the most useful addition for UK conditions. S6 is S2 plus whole-footwear water resistance, marked WR. S7 is S3 plus WR. Before 2022, WR had to be added to S2 or S3 as a separate marking, and many buyers missed it. Now it has its own category.
The distinction that matters: WPA tests the upper material, while WR tests the whole shoe as an assembly. If you need footwear that keeps water out in sustained wet conditions, look for WR, S6 or S7, not S2 or S3.
What the Additional Marking Codes Mean
Beyond the category code, individual letters certify specific tested properties: A for antistatic, E for energy absorption, P for penetration resistance, WPA and WR for water resistance, SR for additional slip resistance, FO for fuel oil resistance, and several specialist markings.
| Code | What it certifies |
|---|---|
| A | Antistatic: electrical resistance between 0.1 MΩ and 1,000 MΩ |
| E | Energy absorption of the seat region, at least 20 J |
| P / PL / PS | Penetration resistance of at least 1,100 N |
| WPA | Water penetration and absorption resistance of the upper (replaced WRU) |
| WR | Water resistance of the whole footwear |
| SR | Additional slip resistance, tested on ceramic tile with glycerine |
| FO | Outsole resistant to fuel oil. Optional since 2022, previously mandatory for S1 to S3 |
| HRO | Outsole resistant to hot contact, tested at 300 °C for 60 seconds |
| HI | Heat insulation of the outsole complex |
| CI | Cold insulation of the outsole complex |
| M | Metatarsal protection, tested at 100 J |
| AN | Ankle protection |
| CR | Cut resistance of the upper |
| SC | Scuff cap abrasion resistance |
| LG | Ladder grip, tested against a ladder rung |
A full label therefore reads something like "EN ISO 20345:2022 S3L SR HRO", which tells you the standard, the version, the category, the insert type and two additional tested properties. Our EN ISO 20345 certification guide works through every code in more depth.
Which Rating Does Your Job Need?
Dry indoor work with sharp debris underfoot usually needs S1P. Damp indoor work needs S2. Outdoor, wet or mixed terrain needs S3 or S7. Wash-down and standing water need S5. Your employer's risk assessment sets the actual requirement.
| Environment | Usual minimum | Why |
|---|---|---|
| Warehouse and distribution | S1P | Dry concrete, impact risk, banding staples underfoot |
| Vehicle workshop and garage | S1P with FO | Dry floors, dropped tools, oil contact on the outsole |
| Indoor fit-out and decorating | S1P | Dry interiors, nails and screws on the floor |
| Commercial kitchen | S2 or S3, SR preferred | Standing water, grease, frequent wash-down |
| Healthcare and clinical support | S1 or S1P per policy | Sharps risk, wipe-clean requirement, long shifts |
| Construction and groundworks | S3 or S7, often boots | Wet ground, uneven terrain, penetration risk |
| Working at height and ladder use | S3 minimum, LG where relevant | Rung grip, ankle stability, weather exposure |
| Food production and wash-down | S4 or S5 | Constant water and cleaning chemicals |
Treat this table as a conversation starter with your safety officer, not a substitute for one. Conditions differ between two sites with the same name on the door, and UK law makes the workplace risk assessment decisive. Employers must provide required PPE free of charge, which is covered in our guide to the UK PPE at Work Regulations. For a direct four-way comparison of the most common codes, see S1, S1P, S2 or S3 safety shoe rating.
Are Safety Boot Ratings Different From Safety Shoe Ratings?
No. Safety boot ratings use the identical SB to S7 codes under the same standard. A boot and a shoe carrying the same rating have passed the same tests. The difference is coverage and ankle support, neither of which is part of the category code.
This causes constant confusion, so it is worth being direct. There is no separate boot standard. An S3 boot and an S3 shoe both have a 200-joule toe cap, upper water resistance, a puncture-resistant insert and a cleated outsole. What the boot adds is height, which brings ankle support, better debris exclusion and more splash protection.
If ankle protection is specifically required, look for the AN marking rather than assuming a boot provides it. AN is a tested property with its own criteria, and plenty of boots do not carry it.
What Changed From the 2011 Standard?
The 2022 revision made slip resistance a basic requirement and retired SRA, SRB and SRC. It renamed WRU to WPA, made fuel oil resistance optional, split puncture resistance into P, PL and PS, and added the S6, S7, SC and LG codes.
| Area | EN ISO 20345:2011 | EN ISO 20345:2022 |
|---|---|---|
| Slip resistance | Optional, marked SRA, SRB or SRC | Mandatory basic requirement. Optional glycerine test marked SR |
| Upper water resistance | WRU | WPA |
| Fuel oil resistance | Mandatory in S1, S2, S3 | Optional, marked FO when claimed |
| Puncture resistance | P only | P, PL and PS |
| Waterproof categories | WR added to S2 or S3 | New categories S6 and S7 |
| New markings | None | SC (scuff cap abrasion), LG (ladder grip) |
Certificates issued under the 2011 version stay valid until they expire, so both vocabularies are still in circulation. If a 2026 listing advertises SRC, either the stock predates the revision or the product copy has not been updated. Neither means the shoe grips badly, but it does tell you something about how carefully the seller maintains its information.
How to Check a Shoe's Rating
Look for the permanent marking stamped inside the tongue, collar or quarter lining. It must show the standard and year, the category code, the size, the manufacturer and the date of manufacture. The label overrides the product listing.
- Find the permanent marking. Inside the tongue or collar, not on a swing tag or the box.
- Read the standard and year. EN ISO 20345:2022 or 2022+A1:2024 is current.
- Check the category against the listing. If the page says S3 and the label says S1P, the label is correct.
- Ask for the certificate. Safety footwear is Category II PPE, so an independent body must carry out a type examination and issue a certificate naming itself and its four-digit number. A legitimate seller can produce it, along with the Declaration of Conformity.
Frequently Asked Questions
What is the highest safety shoe rating?
S7 is the highest rating for Class I footwear, combining S3 with whole-footwear water resistance. S5 is the highest for Class II moulded footwear. Neither is universally best, because they suit different constructions and different work.
What is the difference between S1P and S3?
Both include a 200-joule toe cap, antistatic properties, an energy-absorbing heel and a puncture-resistant insert. S3 adds upper water resistance and a cleated outsole, which is why it is the usual minimum for outdoor and construction work while S1P is a dry indoor specification.
Is S2 better than S1P?
Neither is better overall. S1P has a puncture-resistant insert and no water resistance. S2 has upper water resistance and no puncture-resistant insert. Choose based on whether your main hazard is sharp debris or moisture.
What does the L or S mean after a rating?
They indicate a non-metallic penetration-resistant insert. L means it was tested with a 4.5 mm point, S means it was tested with a finer 3 mm point. So S3S has the same protection package as S3, with a non-metallic insert tested against thinner objects.
Are SRA, SRB and SRC still used?
Not under the current standard. Slip resistance became a mandatory basic requirement in the 2022 revision, so those three markings were retired. The optional SR marking now indicates a further test using glycerine on ceramic tile.
Do safety shoe ratings tell you the toe cap material?
No. The rating specifies the protection level, not the material. A 200-joule cap may be steel, aluminium or composite, and all three pass identical impact and compression tests. Only the P, PL and PS codes tell you anything about material, and they refer to the sole insert rather than the toe.
Which safety shoe rating do most UK warehouses require?
S1P is the most common minimum for dry indoor warehouse floors, covering impact risk, static and sharp debris underfoot. Sites with yard work, loading bays or wash-down areas often specify S3 instead. Always confirm with your employer.
Using This Page
Safety shoe ratings are a closed list, not a marketing scale. Every property a shoe has must be earned through a test and declared with a code, so if water resistance, heat resistance or metatarsal protection is not in the marking, the shoe has not been tested for it. That principle makes the table at the top of this page more reliable than any product description.
For transparency: we make safety footwear ourselves. Xnexz produces trainer-format shoes certified in category S1PL FO SR, which is a light-duty specification intended for dry indoor settings where an employer accepts S1P. We do not make S3, S6, S7, S4 or S5 footwear, and we do not make boots, so for wet, outdoor or specialist work the right answer is another brand. We have set out that position in full in the complete UK safety shoes buyer's guide.
- EN ISO 20345 certification guide: the standard behind every rating on this page.
- S1P safety shoes: the complete UK guide: the most common rating, in detail.
- S1, S1P, S2 or S3: a direct comparison of the four codes most UK buyers choose between.
- UK PPE at Work Regulations: who decides your rating, and who pays for it.
