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Safety footwear catalogues in the UK and EU are organised around a handful of overlapping systems: the EN ISO safety ratings, the PPE risk categories, the physical style of the footwear, and the industry it is intended for. Buyers who understand how these systems fit together can read any supplier’s line sheet quickly — and write clearer specifications for their own ranges.
This guide walks through each classification layer in turn.
The two base standards: safety vs occupational
Everything starts with a split between two standards:
- EN ISO 20345 — safety footwear. Fitted with a toe cap tested to 200 joules of impact. Products carry an “S” rating.
- EN ISO 20347 — occupational footwear. No protective toe cap; designed for roles that need slip resistance or other properties without impact protection (hospitality, nursing, cleaning). Products carry an “O” rating.
Almost everything sold as a “safety shoe,” “safety trainer,” or “safety boot” falls under EN ISO 20345.
The S ratings under EN ISO 20345:2022
Each S class builds on the one below it. In outline:
- SB — the baseline: 200 J toe cap protection. General low-risk environments.
- S1 — SB plus closed heel, antistatic properties, and an energy-absorbing heel. Dry indoor work: light manufacturing, dry warehousing.
- S1P / S1PL / S1PS — S1 plus a puncture-resistant midsole. The suffix identifies the midsole type: P is steel, PL is composite tested with a 4.5 mm nail, PS is composite tested with a 3.0 mm nail. Indoor construction, joinery, and logistics with underfoot puncture risk.
- S2 — S1 plus a water-resistant upper (WPA). Wet indoor environments and food production.
- S3 / S3L / S3S — S2 plus a puncture-resistant midsole and a cleated outsole. The standard specification for construction sites and outdoor contracting.
- S4 — S1-level protection in an all-polymer or rubber wellington. Wet industrial settings, agriculture, cleaning.
- S5 — S4 plus midsole puncture resistance and a cleated outsole. Heavy civil engineering, muddy terrain, utilities.
- S6 / S7 — new classes introduced in the 2022 standard: S6 is S2-level protection plus whole-footwear waterproofing (WR), and S7 is the waterproof equivalent of S3. Severe weather, standing water, infrastructure maintenance.
For the full detail on what changed in the 2022 revision — including the retirement of the SRC slip codes — see our guide to understanding EN ISO 20345:2022.
PPE risk categories
Under EU Regulation 2016/425 and the equivalent UK PPE legislation, protective equipment is divided into three risk categories, which determine the certification route:
- Category I (minimal risk) — covers basic occupational footwear protecting against minor hazards.
- Category II (intermediate risk) — the category for standard industrial safety footwear certified to EN ISO 20345. Requires type examination by a notified body.
- Category III (high risk) — specialised protection against hazards that can cause very serious harm, requiring third-party testing plus ongoing production surveillance. Examples include chainsaw-protective boots (EN ISO 17249), chemical-hazard boots, and high-voltage electrical footwear.
For most brands and wholesalers, day-to-day ranges sit in Category II.
Classification by style
Catalogues also sort footwear by silhouette, because style determines comfort, mobility, and where the product will actually be worn:
- Safety trainers / sneakers — low-cut, lightweight, athletic styles, usually with composite toe caps. The fastest-growing segment, driven by warehousing, courier work, and light assembly.
- Safety shoes (low-cut) — traditional lace-up and uniform styles, including executive/brogue designs with hidden toe caps for managers moving between office and site.
- Safety boots (ankle and mid-cut) — 6-inch support boots for rough terrain and heavy construction.
- Rigger boots — pull-on boots with deep ankle coverage.
- Safety wellingtons — fully moulded rubber, PVC, or PU boots (S4/S5, and S6/S7 where certified) for wet, muddy, or chemical environments.
Classification by industry
Most wholesaler catalogues layer a “shop by industry” view on top, because each sector has a predictable feature profile:
- Construction and trades — S3 or S7 ratings, puncture-resistant midsoles, ankle support, scuff caps (SC).
- Logistics and warehousing — lightweight S1P-class trainers with ESD protection and heel cushioning.
- Food processing and healthcare — washable microfibre uppers (S2/S4), white colourways, enhanced slip resistance (SR).
- Foundry, welding, and heavy metallurgy — heat-resistant outsoles (HRO), quick-release fastening, metatarsal guards (M).
- Cold storage and utilities — cold insulation (CI) and full waterproofing.
Feature and component markings
Finally, individual protective features carry their own codes, which appear alongside the S rating on the label and certificate:
- ESD — dissipates static electricity; required around sensitive electronics.
- HRO — outsole withstands 300°C contact heat for 60 seconds.
- CI / HI — cold insulation / heat insulation of the sole unit.
- FO — fuel and oil resistant outsole (optional under the 2022 standard).
- WPA / WR — water-resistant upper / fully waterproof footwear.
- SC / LG — scuff cap abrasion resistance / ladder grip (new in 2022).
- Metal-free / composite — fibreglass, carbon fibre, or textile components in place of steel; lighter and suitable for airport-security and electronics environments.
Specifying with confidence
A well-written product specification combines these layers: an S class, the midsole type where relevant, and the feature codes the working environment demands — for example, “EN ISO 20345:2022 S1PS, ESD, metal-free” for an electronics warehouse trainer.
If you are building or refreshing a range and want to confirm what our factory network can certify and produce, send us your target specifications — we will come back with feasibility, MOQs, and lead times.
This guide is general information for buyers, not legal or compliance advice. Always verify certificates and markings for the specific products you purchase.