ISO Standards for Translation: 17100, 18587 and More

What ISO 17100 actually requires

ISO 17100 is the international standard for translation services. It was published in 2015 and replaced the earlier European standard EN 15038. Its subject is the production process: who is allowed to touch the work, what steps the work has to pass through, and what the provider has to be able to show afterward. Read once, it is far less mysterious than proposals make it sound.

The requirements fall into four groups.

• Translator qualifications. The standard lists acceptable routes to competence: a recognized degree in translation, a degree in another field plus two years of full time translation experience, or five years of full time professional experience. A provider working to the standard keeps evidence for every linguist on the file, not a general statement that its translators are qualified.
• Revision by a second person. This is the core requirement and the one most often skipped in practice. Every translation is checked against the source by a second linguist who is not the translator. The standard calls this revision. It is not a proofread of the target text alone, and it is not the translator rereading their own work the next morning.
• Project management and specifications. Someone has to own the project, agree the specifications with the client, brief the linguists, and handle queries. The standard also expects an agreement covering confidentiality and the handling of client material.
• Records and feedback. Project records, linguist assignments, and client feedback have to be retained so that a given delivery can be reconstructed later. This is the part that turns process claims into something checkable.

Notice what is absent. ISO 17100 does not define an error rate, does not grade output, and says nothing about whether the translator understands hydraulics. It gives you a floor under the process. The ceiling still depends on who was assigned to your file, which is why we publish the profiles of the specialists who handle each language rather than leaving the roster abstract.

Compliant, aligned, certified: the words matter

Three claims circulate in this market and they mean different things.

Following the standard, sometimes written as compliant with or aligned to, means the company has read the requirements and built its workflow to meet them. Nobody outside the company has verified that. The claim is only worth what the company's transparency is worth, and a buyer can test it by asking process questions: who revised this file, what are that person's credentials, show me the query log.

Certification means an independent certification body has audited the company against the standard, issued a certificate with a number and a defined scope, and will return for surveillance audits. Certification bodies are themselves accredited by a national accreditation body, which is what makes the chain meaningful. A certificate names the standard, the certified entity, the scope of activities and sites covered, an issue date, and an expiry date.

The gap between the two is real, and it is mostly a gap in verification rather than in daily practice. A certified provider has proven to an auditor that its records match its claims. An uncertified provider following the standard may run an identical process, or may not, and you have no external evidence either way. Both situations exist in this industry, and a buyer is entitled to know which one is in front of them.

We are explicit about this because the alternative is a claim we cannot back up when someone asks for the document. Our memberships are similarly checkable: Techniwords is a member of the American Translators Association and of GALA, both of which can be confirmed in the respective directories. Membership is not certification either, and we do not present it as such. The reasoning behind these choices is set out further on our company background page.

ISO 18587: post-editing of machine translation

ISO 18587 covers what happens after an engine produces output. It defines the competences a post-editor needs, which overlap with but are not identical to translator competences, and it describes two service levels. Light post-editing aims at content that is accurate and understandable, with machine phrasing left in place where meaning is intact. Full post-editing aims at output comparable to human translation, with terminology aligned and unnatural constructions rewritten.

The standard is useful to buyers for one specific reason: it gives you vocabulary to pin down what a vendor is selling. A quote that says post-editing without saying which level is a quote you cannot compare against another. Ask which level, ask what happens to terminology, and ask whether the raw output was measured before the rate was set. Our own approach to post-edited translation states the level on the quote, and post-edited work is never delivered as human translation.

ISO 11669: writing the specifications before the work starts

ISO 11669 is the least known of these documents and arguably the most useful for buyers. It is guidance, not a certifiable requirement, and it deals with translation project specifications: the parameters that should be agreed before a project starts. Source content characteristics, target audience, purpose, register, terminology sources, file requirements, deadline, and the qualifications expected of the linguists.

Most disputes we see at delivery trace back to a parameter nobody wrote down. The client expected Latin American Spanish and received European Spanish. The client assumed the figures would be reworked in InDesign and the vendor assumed a bilingual table. Neither party was dishonest. The specification was simply never made explicit, which is what ISO 11669 exists to prevent, and it is why our project workflow starts with a written brief rather than a purchase order.

ISO 9001 and ASTM F2575: two frequent sources of confusion

ISO 9001 is a generic quality management standard applicable to any organization, from a machine shop to an accounting firm. It requires a company to define its processes, monitor them, and improve them. It says nothing about translation. A translation company certified to ISO 9001 has demonstrated that it manages its processes consistently. It has not demonstrated that a second linguist revises every file, because 9001 has no opinion on that question. Some vendors present a 9001 certificate as if it validated their translation methodology. It does not, and a buyer who reads the scope line on the certificate will see it.

ASTM F2575 is the American entry in this field, a standard guide for quality assurance in translation. Like ISO 11669, it is a guide rather than a set of certifiable requirements, and its focus is also on defining project parameters between requester and provider. US buyers occasionally see it referenced in federal or state solicitations. It is a sensible framework for structuring an RFP, and no vendor can be certified to it.

Standard	Scope	Certifiable	What it does not cover
ISO 17100	Translation services: linguist competence, revision by a second linguist, project records	Yes, by an accredited certification body	Output quality of any individual project, subject matter depth
ISO 18587	Post-editing of machine translation output, light and full levels	Yes	Which content is suitable for machine translation in the first place
ISO 11669	Guidance for defining translation project specifications	No, it is guidance	Production requirements, who is qualified to translate
ISO 9001	Generic quality management system for any industry	Yes	Anything specific to translation, including revision
ASTM F2575	US guide to quality assurance parameters in translation	No	Linguist qualification requirements, audit trail

What none of these standards guarantee

A standard can require that a second qualified linguist revises the file. It cannot require that the reviser knows what a torque converter does, that the translator recognized an ambiguity in the source and raised a query, or that the terminology matches what your German subsidiary has used for a decade. Those depend on individual talent and on how carefully the provider matched people to your subject matter.

This is the honest limit of process standards, and it applies to certified and uncertified providers equally. A certified company that assigns your medical device instructions to a generalist because the specialist was booked has met the standard and failed you. An uncertified company that assigns the right specialist and runs a real revision pass has served you well with no certificate to show for it. Standards raise the floor. They do not select your translator, and no audit ever reads a sentence of your manual.

Practically, this means credential checks should sit alongside standards checks. Ask which named linguist will work on your account, what their sector background is, and whether the same person will handle the next revision of the document. Those answers predict outcomes better than any logo on a proposal, and they are the reason our quality control workflow documents who does what at each step.

How to read standards claims in a proposal

Procurement teams evaluate translation vendors a few times a decade, which is exactly why vague claims survive. A short interrogation resolves most of it.

1. "We are ISO certified." Ask which standard, which certification body, what scope, and what expiry date. A vendor with a certificate answers in one email and attaches a PDF. Vagueness here is the strongest single red flag in this category.
2. "ISO 9001 certified translation quality." Read the scope line on the certificate. If it covers management processes, it says nothing about how your file will be translated.
3. "ISO 17100 compliant." A legitimate claim, and one we make ourselves. Test it with process questions rather than accepting it as a badge: who revises, what are their credentials, how are queries logged, what records are kept.
4. Certification logos with no number. A logo is not a certificate. Certification bodies publish registries, and most claims can be checked in a few minutes.
5. Certification held by a parent or partner company. Certificates are issued to a legal entity and a scope of sites. If the certificate names a different company, ask whether the work is actually performed by that entity.
6. Standards claims with no revision step in the quoted price. If the price is quoted for translation only and revision appears as an option, the workflow being sold does not meet ISO 17100 regardless of what the boilerplate says.

That last point is worth sitting with. Independent revision by a second linguist is where a meaningful share of the cost of a compliant process lives. A quote that undercuts the market by half has usually removed it, whatever the footer of the proposal claims. Our vendor selection guide works through the rest of the evaluation criteria, including the ones where another agency may suit you better than we do.