ANSI vs EN 388: Why the Two Cut Ratings Don’t Convert

ANSI vs EN 388: Why the Two Cut Ratings Don’t Convert

Ask any PPE distributor that sells on both sides of the Atlantic about their least favourite customer question, and you will hear it immediately: what is the EN equivalent of an A5? Or the reverse: we have F on the glove, what is that in ANSI? The answers you find online are usually tables that look authoritative and disagree with each other. That disagreement is not an accident. ANSI and EN 388 measure cut resistance with fundamentally different machines, different blade movements, and different units, so there is no clean conversion. This article explains the mechanical difference, why grams and newtons still do not map one to one, how the approximation tables used in the trade should and should not be used, and how to write specifications that hold up in both markets.

Two Different Machines: Rotating Coupe Blade vs Straight TDM Blade

The classic EN 388 cut test is the Coupe test. A circular blade rotates under a fixed load and moves back and forth across the sample, and the result is calculated by comparing how many cycles the blade needs to cut the sample against a reference material. The index produced is expressed on a one-to-five scale, and this is the origin of the familiar EN cut levels one through five.

The TDM test, used by ANSI/ISEA 105-2016 and also by the EN 388 position five rating, works differently. A straight blade travels in one direction across the sample under a series of different loads, and the result is the load at which cut-through happens. In ANSI the result is expressed in grams, producing the A1 to A9 scale. In EN 388 the same mechanical method is expressed in newtons, producing the letter ratings A through F, where A equals two newtons, B equals five newtons, C equals ten newtons, D equals fifteen newtons, E equals twenty-two newtons, and F equals thirty newtons.

The difference is not cosmetic. A rotating blade keeps contacting and re-contacting material in a way that interacts with the sample differently from a single straight draw. Materials that blunt, clog, or entangle a rotating blade, such as fibres made with glass or steel content, can score very differently under the two methods. That is why EN 388:2016 keeps both: the Coupe index in position two of the marking and the TDM letter in position five.

Grams vs Newtons: Why There Is No One-to-One Mapping

Grams and newtons are both measures of force, and mathematically one gram-force converts to a fraction of a newton. That tidy arithmetic tempts buyers into thinking an ANSI gram figure should translate directly into an EN newton figure. It does not, because the two results come from different physical events.

The Coupe result is a relative index: how the sample performed against a reference material under rotating conditions. The TDM result is an absolute load: the force at which cut-through occurred under straight-blade conditions. A material can resist a straight draw well while interacting poorly with a rotating blade, or the reverse. Laboratory conditions add further variation, since sample preparation, blade condition, and machine settings all influence outcomes. The result is that two gloves with identical TDM performance can carry different Coupe indices, and two gloves with the same Coupe level can produce different TDM loads. Any table that claims an exact equivalence is asserting something the physics does not support.

Approximation Tables: What Factories Actually Use, and Their Limits

In practice, factories and distributors do use rough correspondence tables for planning purposes, and buyers will keep asking for them. There is nothing wrong with using an approximation to start a conversation, narrow a range, or guess which constructions to sample. The limits are what matter.

• An approximation is not a specification. Never write a contract, tender, or product label using a converted value. Converted figures fail audits and undermine complaints handling.
• An approximation is not a marketing claim. Stating an EN rating you have not tested, based on an ANSI result you do have, is a compliance risk under EU Regulation 2016/425, which requires type examination by a notified body for this product category.
• An approximation expires when the range changes. A rough mapping that held for one construction or fibre blend may not hold for the next one, especially when yarn composition changes.
• The reliable source is dual testing. If a glove is sold into both markets, the correct approach is tested results under both standards, reported in the units each market uses.

When a customer presses for a conversion, give them the honest version: an approximation can guide which samples to trial, and only tested results can go into the specification or onto the glove.

Writing Specifications That Work in Both Markets

Spec language is where this problem is won or lost. A specification written for a single market often causes trouble the moment the same glove ships internationally. Write for both from the start.

• Name each standard explicitly. Write ANSI/ISEA 105-2016 with the A-level and grams, and EN 388:2016 with the full six-digit marking, never a bare number that could be read as either.
• Quote the EN 388 marking in full. The six positions cover abrasion, the Coupe cut index from one to five, tear, puncture, the TDM cut letter from A to F, and impact, where P means passed and X means not tested. Quoting all six avoids the old habit of treating one figure as the whole rating.
• State the test basis in the specification. Note whether a cut figure comes from the Coupe method or the TDM method, so a reviewer can interpret it correctly.
• Require documentation, not conversion. Ask suppliers for test results under each named standard rather than accepting a converted equivalent.
• Align labels with documentation. Whatever appears on the glove, the box, and the technical file must match the tested results for each standard claimed.

This discipline costs little and protects everything: your listings, your audits, and your ability to answer when a safety manager in Ohio or a notified body reviewer in Europe asks where a number came from.

Frequently Asked Questions

Can I use a conversion table from another supplier?

You can use it as a rough planning aid, but not as a specification or a labelling basis. Only tested results under the named standard should be quoted, printed, or contracted.

Which rating should I put first on packaging for a dual-market glove?

Lead with the rating of the market where the product is being sold, and print both complete markings. Never print a converted figure that was not actually tested.

Why do two gloves with the same A-level have different EN letters?

Because the tests measure different physical events. The TDM test and the Coupe test respond differently to fibre composition and construction, so identical performance in one method does not guarantee identical performance in the other.

Is the EN 388 TDM letter the same as the ANSI A-level?

They share the same TDM test mechanics, but they are reported on different scales and units, with the EN letter running A to F and the ANSI scale running A1 to A9. Quote each result in its own system and do not treat them as interchangeable labels.

What should I ask a factory that only quotes one standard?

Ask whether tested results under the other standard are available for that construction, and request the reports. If the factory can only convert from one standard to the other, treat the glove as single-market until proper testing is done.

Build a Dual-Market Range With INTEGRITY GLOVE

If you sell protective gloves into both North American and European markets, we can help you specify constructions with tested results under both systems and documentation that matches your labels. Contact INTEGRITY GLOVE by email at [email protected] or on WhatsApp at +86 1515 289 1159. For minimum order quantities and lead times, please contact us for details, as these vary by construction and programme.