OEKO-TEX Standard 100: What It Covers and What It Doesn’t

OEKO-TEX Standard 100 is a product-level chemical safety label for textiles. It tests a finished fabric, garment, or component for harmful substances, and it tells a buyer one thing: what reaches the skin is within tested limits. That is the whole scope, and the boundary matters because brands keep assuming the label covers more than it does. For a deeper look at dye chemistry and the questions to put to your mill, see our guide on low-impact dyes for wool and knits.

Fursone’s Wenzhou mill holds ISO, GRS, and OEKO-TEX certification, and our buying conversations show the same gap every month: brands treat one sustainability badge as a catch-all. GRS verifies recycled content and chain of custody, and it does not touch chemical safety. OEKO-TEX Standard 100 tests chemicals, and it says nothing about recycled content. This guide covers what Standard 100 tests, how the product classes work, and the verification steps a buyer can run before approving a fabric.

What OEKO-TEX Standard 100 Actually Is

Standard 100 is the best-known label in the world for textiles tested for harmful substances, and it operates at product level. The certificate attaches to a specific article with a specific composition, not to a company or a product line in general. When a mill says “we are OEKO-TEX certified,” the precise question is which articles, which product class, and which testing institute issued the certificate. The official OEKO-TEX Standard 100 official page and its Standard 100 factsheet carry the scope in plain terms, and the OEKO-TEX network spans more than 21,000 companies worldwide.

The test applies to every component of the article: yarn, dye, and finish. A tweed with a certified wool face and an uncertified lining does not pass as a Standard 100 article, because the label covers the whole product. For buyers, that means the certificate you request should name the fabric construction you are actually ordering, including any metallic yarn, elastane, or interlining, since each component is tested.

Standard 100 is voluntary. No law forces a mill to certify, and no customs gate requires the label for import. What makes it mandatory in practice is the retail chain: many European retailers and children’s wear buyers require it as a condition of listing, and its criteria are often the basis of restricted substances lists (RSLs) that retailers enforce. A fabric can clear customs without it and still be rejected at the buyer’s compliance desk.

The 300+ Substances in the Test Scope

The test catalogue covers over 300 regulated and unregulated substances. The groups include pesticides, phthalates, formaldehyde, nickel, PFAS, and carcinogenic amines, with limit values set for each. The “unregulated” part matters: Standard 100 goes beyond legal minimums, which is why its criteria are stricter than general import regulations and why retailers adopt them as their own RSL baseline.

Two examples show how the limits land on real fabrics. Formaldehyde is a common resin finish byproduct on wrinkle-resistant and some wool-blend fabrics, and Standard 100 sets a limit far below what an untreated fabric might release. Nickel is relevant to metal components and to metallic yarns in tweed, where the standard’s release limits decide whether a metallic accent is safe for direct skin contact. A metallic tweed carrying a Standard 100 certificate has had its metallic yarn tested, not just its wool.

Because the catalogue includes unregulated substances, the standard functions as a moving target that stays ahead of legal minimums. Retailer restricted substances lists are often built directly from Standard 100 criteria, which is why a fabric that passes import-level checks can still fail a retailer’s compliance desk. For a mill, holding certification means re-testing when the criteria update, and that is why the certificate date and the criteria edition matter as much as the certificate itself. A two-year-old certificate does not prove today’s fabric meets today’s limits.

Product Classes I-IV

Standard 100 assigns every certified article a product class based on skin contact, and the class decides which limits apply. Class I covers baby articles up to three years old and carries the strictest limits. Class II covers articles worn directly against the skin, which is where adult apparel sits. Class III covers articles with no direct skin contact, such as outerwear linings worn over a garment. Class IV covers decoration and furnishing materials.

Buyers should match the class to the end use. A tweed jacket worn over a shirt or blouse can legitimately be Class II, because it touches the skin on the collar and cuffs. A baby knit must be Class I, and a brand that accepts a Class II certificate for babywear has already failed its own compliance review. When you request a certificate from the mill, state the class in the request; the certificate you receive should name it.

What It Does Not Cover

Standard 100 stops at chemical safety. It does not verify recycled content, organic farming, animal welfare, carbon footprint, or factory working conditions. A fabric can be 100% recycled, GRS-certified, and still contain harmful levels of formaldehyde or heavy metals if the recycling process introduced contaminants, and the reverse is also true: a fully Standard 100-certified fabric can be made from virgin fiber with no sustainability story at all.

Each claim needs its own certificate. Recycled content and chain of custody belong to GRS, which requires at least 50% recycled content in a product and tracks it with scope and transaction certificates. Organic fiber belongs to GOTS. Wool sourcing belongs to RWS. Labor conditions belong to social audits like BSCI or SMETA. When a supplier presents one badge as proof of all of them, that is the moment to ask for the certificate list, not the logo.

The real-world cost of the confusion shows up in container rejections. Brands have shipped eco-knit fabric to European children’s wear accounts with the recycled story in place and no OEKO-TEX test on file, and the container was refused at compliance review because chemical safety documentation was missing. The fabric was legal to import and fully recycled; it was not sellable to that retailer. That gap, between what the label proves and what the buyer assumes, is the reason this scope check belongs in the sample approval stage, not the shipping stage.

Our GRS vs OEKO-TEX comparison covers the certification decision in detail, and the GOTS vs GRS certification guide handles the organic-versus-recycled choice. For wool programs, the RWS explained for tweed guide maps the sourcing standard onto tweed production.

OEKO-TEX vs GRS for Your Order

The two labels answer different questions, and most orders need to know which one the retailer will ask for. GRS answers “what is the recycled content and can you prove it?” Standard 100 answers “is this chemically safe for the intended skin contact?” An eco knit program sold to a European children’s wear account needs both, because the retailer enforces recycled content claims and skin-safety limits separately.

The cost structure reflects the split. GRS certification cost is built into the per-meter unit price at the mill, and it does not cover chemical safety testing. Standard 100 testing is a separate process with its own laboratory costs and certificate renewal. A buyer comparing FOB prices across mills should ask which certifications are included in the quoted meter price, because the difference between “GRS-certifiable” and “GRS-certifiable plus Standard 100” is real money per meter.

Regulation is pushing the two labels closer together. Under the EU Green Claims Directive, recycled content claims sold in the EU increasingly require third-party certification like GRS, so a brand that markets “recycled” needs the chain-of-custody paper even if no retailer asks for it. Skin-safety claims, by contrast, are policed by the retailers themselves through RSLs built on Standard 100 criteria. A brand selling into the EU with both claims needs both certificates, and the mill’s quote should name which one is included.

Our sustainable program demonstrates the stack in practice. The sustainable tweed fabric design program builds recycled content and certified inputs onto the same production floor, and the fabric certifications for luxury knits guide lists which certificates pair with which product claim.

How Buyers Verify a Certificate

Verification takes ten minutes and needs three documents. First, the certificate itself, which names the certified company, the article, the product class, and the testing institute. Second, the certificate number and additional code, which the OEKO-TEX system can trace online; a certificate number that does not resolve is a red flag. Third, the scope: does the certificate cover the exact construction you are ordering, including metallic content, elastane, or interlining?

Check the expiry as well. OEKO-TEX certificates are time-limited, and renewal requires a new license fee and laboratory testing. A certificate from a previous production year does not automatically cover the current order, so ask for the certificate tied to the current batch, and ask the mill to confirm the fabric in the container is the article on the certificate. Retailers do exactly this check before listing, and a buyer who skips it inherits the rejection.

The same discipline applies to the test report. Ask whether the report comes from the production lot or from a previous sample. A report issued for a lab dip does not prove the bulk fabric meets the limits, because dye lots, finishes, and component batches change between sampling and production. The certificate and the production-lot report together close the loop: the certificate proves the article type, and the report proves the batch you are buying.

The practical sequence for a new order: request the current certificate, verify the number online, confirm the article and class match your spec, and ask for the test report covering your components. If the mill hesitates on any of the three, treat it as a compliance risk, not a paperwork delay.

FAQ

What does OEKO-TEX Standard 100 test for?

It tests for over 300 regulated and unregulated harmful substances, including pesticides, phthalates, formaldehyde, nickel, PFAS, and carcinogenic amines, across every component of the article.

Is OEKO-TEX Standard 100 mandatory?

No law requires it, but many European retailers and children’s wear buyers enforce it as a listing condition, and its criteria often form the basis of retailer restricted substances lists.

What is the difference between OEKO-TEX and GRS?

OEKO-TEX Standard 100 verifies chemical safety for skin contact. GRS verifies recycled content and chain of custody. The two labels answer different questions and are often required together.

What is OEKO-TEX Class 1?

Class I covers baby articles up to three years old and applies the strictest substance limits of the four product classes.

How long is an OEKO-TEX certificate valid?

Certificates are time-limited and renewed with a new license fee and laboratory testing. Buyers should request the certificate tied to the current batch and verify the number online.

Conclusion

OEKO-TEX Standard 100 is a chemical safety label with a precise scope: over 300 substances tested on every component, product classes I-IV deciding the limits, and no claims about recycled content, fiber origin, or factory conditions. Match the class to the end use, pair the certificate with GRS or GOTS when the claim demands it, and verify the certificate number, scope, and expiry before approving bulk.

When you source certified tweed or knit from Fursone, request the current OEKO-TEX and GRS certificates with your tech pack, and we will confirm the article and class match your spec before sampling. Samples return within 7 days from the Wenzhou floor, and certified stock starts at 100 meters. Request a quote with your target certification and product class.

For the construction-level detail, see our biodegradable knit fabric guide.