How do you read a safety footwear marking from another country?

Short answer: three systems certify work boots in North America and Europe, and they do not share notation. The United States uses ASTM F2413, a stitched-in alphanumeric line. Canada uses CSA Z195, a set of coloured symbols on the outside of the boot. Europe uses EN ISO 20345, an S-class code such as S1P or S3. They are not interchangeable for compliance: OSHA names ASTM, Canadian jurisdictions name CSA, and an imported boot marked S3 only satisfies 29 CFR 1910.136 if your employer documents it as at least as effective.

Safety footwear standards compared: ASTM vs CSA vs EN ISO (2026 guide)

Anyone who buys work boots internationally, works a cross-border contract, or simply orders from a marketplace seller eventually finds a boot whose marking does not look like anything OSHA describes. A European boot says S3 SR. A Canadian boot has a green triangle stamped on the outside. A US boot has four stitched lines starting ASTM F2413-24. This guide decodes all three safety footwear standards, sets out what each one actually tests, and answers the question that matters most for compliance: which marking your regulator will accept. It is written for safety managers, procurement teams and cross-border crews.

Part 1 — The three standards at a glance

Joule and kilonewton equivalents for the ASTM row are unit conversions of the values in the standard (1 ft-lbf = 1.35582 J; 1 lbf = 4.44822 N), provided for comparison only — ASTM states its requirements in ft-lbf and lbf.

Part 2 — Reading a US marking (ASTM F2413)

The US marking is a stitched-in block of up to four lines. Line 1 names the standard and the edition the boot was certified to. Line 2 carries the gender letter and the toe codes: a full-protection boot reads M/I/C or F/I/C. Lines 3 and 4 carry supplemental codes — EH for electrical hazard, PR for puncture resistance, Mt for metatarsal, SD or Cd for static, CS for chainsaw, and, since the 2024 edition, SR or SRO for slip resistance.

Two details catch people out. First, there is no number after the toe letters on a boot certified to F2413-18 or F2413-24 — the I/75 C/75 notation belongs to F2413-11 and earlier, and the lower Class 50 tier was abolished in 2018. Second, OSHA has not adopted the current edition: 1910.136(b) still names the 2005 editions, and newer certifications qualify through the equivalency clause rather than by being listed. The full line-by-line decode is in our ASTM F2413 safety footwear explained reference.

Part 3 — Reading a Canadian marking (CSA Z195)

Canada took a different design decision: instead of a code you have to find inside the boot, CSA Z195 puts coloured symbols on the outside where a supervisor can see them at a glance. Shape and colour carry the meaning.

The conceptual mapping to ASTM is close — green triangle is roughly "safety toe plus PR", the orange omega is roughly EH, the red C is roughly Cd — but the test values are different and the certifications are issued under different schemes. A CSA symbol is not an ASTM marking.

Part 4 — Reading a European marking (EN ISO 20345:2022)

The European system is a ladder. Every class starts from a 200 J toe cap, and each step up adds a defined bundle of properties, so a single short code carries a lot of information.

Two changes in the 2022 edition matter when you compare listings. Puncture resistance split into three codes: P is a metallic insert, PL is a non-metallic insert proven against a 4.5 mm nail, and PS is a non-metallic insert proven against a finer 3.0 mm nail — the more demanding test. And slip resistance changed shape entirely: the ceramic-tile-with-soap test became a basic requirement for every safety shoe, so it is no longer marked, while an optional glycerine test is marked SR. The familiar SRA / SRB / SRC codes were retired.

Part 5 — Why the impact numbers are not a league table

Line the headline figures up and the conclusion looks obvious: EN ISO 20345 at 200 J, CSA Grade 1 at 125 J, ASTM F2413 at about 101.7 J. It is tempting to read that as a ranking of how well each standard protects a foot. It is not, and presenting it that way is the most common error in cross-standard comparisons.

The three standards do not stage the same event. They differ in striker geometry and mass, in how the toe cap is supported during the test, and — critically — in the internal clearance that must remain under the cap for a pass. A standard that demands more residual clearance is harder to pass at the same energy. Comparing only the joule figure ignores all of that.

What you can say safely is narrower and more useful: each standard is internally consistent, each was written against the injury patterns and legal framework of its own jurisdiction, and a boot certified to one of them has not been assessed against the others. That is the fact that drives every practical decision below.

Part 6 — Worked example: "can I wear these boots here?"

A maintenance contractor buys a well-reviewed European boot marked S3 SR and turns up on a US manufacturing site. Work through it in order:

1. Read what the site requires. Almost every US site policy is written as "ASTM F2413-rated safety-toe footwear". The policy, not the regulation, is usually the first gate.
2. Check the regulation behind it. 1910.136(b) names ASTM F2412-2005 and F2413-2005, and ANSI Z41-1999 and Z41-1991. EN ISO 20345 is not on that list.
3. Check the equivalency route. The same paragraph deems footwear compliant where the employer demonstrates it is at least as effective as footwear built to a listed standard. So the S3 boot can be compliant — but only via a determination the employer has to make and be able to produce.
4. Ask who is carrying that burden. In practice, no site safety manager wants to write an equivalence determination for one contractor’s boots. The realistic outcome is that the boot is refused at the gate even though it is, on the numbers, a more demanding toe cap.
5. Buy to the jurisdiction you work in. For US work, that means an ASTM F2413 marking — see our steel toe picks or composite toe picks. For cross-border work, buy dual-certified.

The same sequence runs in reverse for a US boot taken to a Canadian site: the ASTM marking is not a CSA certification, and the Canadian jurisdiction will be looking for the symbols on the outside of the boot.

Part 7 — Practical rules for buying across borders

Read the marking, not the listing. Marketplace copy routinely says "safety toe" or "meets international standards" with no certification behind it. The stitched line or the moulded symbol is the evidence.

A CE mark is not a protection level. It says the product was assessed under EU legislation. The S-class is what states performance, and a CE-marked boot can be nothing more than SB.

Buy dual-certified if you cross the border. Manufacturers selling into both markets commonly carry the ASTM line inside and the CSA symbols outside on the same boot.

Match the hazard first, the jurisdiction second. Whichever system you buy into, the codes only matter if they answer your actual hazard assessment — which is what OSHA 1910.132 requires your employer to have done. Our how to choose safety boots walkthrough runs that step.

Frequently asked questions

Further reading on this site

• ASTM F2413 safety footwear explained — the full US marking decode, code by code.
• When do you need safety toe boots? — what actually triggers the OSHA requirement.
• Steel toe vs composite toe boots — the material trade-off at identical ratings.
• Soft toe vs safety toe boots — and where ASTM F2892 fits.
• Best electrical hazard work boots — what EH does and does not cover.
• Best metatarsal boots — the Mt code and internal vs external guards.
• Safety footwear — the full range of ASTM F2413-rated boots and shoes.
• safety footwear marking selector — answer the hazard questions and it builds the ASTM F2413 line to put on the purchase order.