OEKO-TEX Standard 100 Testing Criteria
What does OEKO-TEX Standard 100 actually test for?
OEKO-TEX STANDARD 100 is a lab test of the finished textile for harmful-substance residues. Every component (thread, button, accessory) is checked against what OEKO-TEX calls "a list of over 1,000 harmful substances," and the limits get stricter the more skin contact the product has (OEKO-TEX). The test is mainly chemical analysis, plus colour-fastness, odour and air-emission checks.
Approach: I read the STANDARD 100 Annex 4 and Annex 6 limit-value tables (Version 03.2026, dated 01.09.2026) and OEKO-TEX's own STANDARD 100 page. Examples below are the Annex 4 limits for baby articles and for articles with direct skin contact.
Product classes. There are four, based on how much skin contact the product has: babies up to 3 years (strictest), direct skin contact (e.g. bed linen), no direct skin contact (e.g. jackets), and home or decorative textiles (e.g. curtains). OEKO-TEX says it reviews the limits at least once a year and claims the criteria cover REACH Annexes XIV and XVII, the US CPSIA and the ECHA Candidate List (OEKO-TEX).
What the limit tables cover
| Group | What is tested, with examples |
|---|---|
| pH | 4.0-7.5 for baby and skin-contact articles; 4.0-9.0 for the other two classes [1] |
| Formaldehyde (free and partly releasable) | Must not be detectable ("n.d.") in baby articles; 75 mg/kg for skin contact, 150 without skin contact, 300 for decoration [2] |
| Extractable heavy metals | 14 metals, e.g. lead 0.2 (baby) / 1 (skin) mg/kg [3], cadmium 0.1 [4], nickel 1 / 4 [5], chromium(VI) 0.5 [6], mercury 0.02 [7] |
| Total heavy-metal content | E.g. lead 90 mg/kg, including metal parts [8]; cadmium 40 [9] |
| Pesticides | 132 entries, e.g. methoxychlor 0.01 mg/kg [10] |
| Chlorophenols and their salts and esters | E.g. sum of monochlorophenols 0.5 (baby) / 3 mg/kg [11] |
| Phthalates | E.g. BBP 500 mg/kg in Annex 4 and 100 in Annex 6 [12] |
| Organotins | E.g. monobutyltin 1 (baby) / 2 mg/kg [13] |
| Bisphenols | E.g. BPA 10 mg/kg [14] |
| Problem dyes | Allergenic disperse dyes, e.g. Disperse Blue 124 at 50 mg/kg [15]; carcinogenic dyes, e.g. Direct Black 38 [16] and lead chromate pigments [17]; Navy Blue is also listed [18] |
| Carcinogenic arylamines (from azo dyes) | 35 entries, e.g. 4-aminoazobenzene 20 mg/kg [19] |
| Chlorobenzenes and chlorotoluenes | 1 mg/kg each [20] |
| PAHs | 25 entries, e.g. acenaphthene 5 (baby) / 10 mg/kg [21] |
| Biocides and flame retardants | Both are listed as product groups, with permethrin and triclosan named [22]. About 45 flame retardants are named (PBBs, PBDEs, HBCDD, TBBPA, borates, chlorinated phosphates), mostly 10 mg/kg each, 50 mg/kg in total [23] |
| Solvent residues | E.g. DMF and DMAc 500 mg/kg [24]; formamide 200 [25] |
| Alkylphenols and their ethoxylates (APs/APEOs) | Nonylphenol 10 mg/kg (Annex 4) / 5 (Annex 6) [26] |
| PFAS | PFAS as a group (OECD definition) [27]. Named PFAS such as PFOA [28] and PFOS [29] at 25 µg/kg; total fluorine 50 mg/kg [30] |
| Other substances | UV stabilisers 100 mg/kg [31]; short- and medium-chain chlorinated paraffins 50 [32]; siloxanes D4/D5 1,000 [33]; preservatives [34]; N-nitrosamines 0.5 [35]; chlorinated solvents and other VOCs, e.g. benzene 1 [36]; cresols 10 [37]; dimethylfumarate 0.1 [38]; quinoline 50 [39] |
| Emissions to air (mg/m³) | Formaldehyde 0.04 [40], toluene 0.1 [41], styrene 0.005 [42], total organic volatiles 0.5 [43] |
| Colour fastness (staining) | To water [44], acidic and alkaline sweat [45] and dry rubbing [46]; baby articles must also be fast to saliva and sweat [47] |
| Odour | "No abnormal odour" [48] |
| Banned or other items | Asbestos [49], synthetic glitter (must be "fast") [50], GMO analysis [51] |
Reading the tables
- Some entries carry a code ("n.a.", "n.i.u.") instead of a number, for example asbestos and the biocide and flame-retardant group lines. The tables don't define these codes, so I haven't interpreted them.
- Annex 6 is often stricter than Annex 4 (phthalates, organotins, alkylphenols, dyes), but not always: antimony is "n.a." for decoration in Annex 4 but 30 mg/kg in Annex 6.
- STANDARD 100 is a voluntary private certification, not law. The limit tables are useful as a screening checklist for REACH Annex XVII, the POPs Regulation and CPSIA, but legal compliance should be confirmed against the regulations themselves.
I can line up specific STANDARD 100 limits against the matching REACH Annex XVII entries if that would help.
What are the product classes?
STANDARD 100 has four product classes. They are set by how much skin contact the textile has, and the limits get stricter as skin contact increases (OEKO-TEX):
| Class | OEKO-TEX definition | Example given |
|---|---|---|
| 1 | Products for babies and children up to 3 years. "This product class has the strictest requirements and limit values." | Diapers |
| 2 | Products with direct skin contact | Bed linens |
| 3 | Products without direct skin contact | Jackets |
| 4 | Home textiles and other decoration materials | Curtains |
Approach: I checked the STANDARD 100 limit-value tables (Version 03.2026, dated 01.09.2026). They show the four classes only as column headings (baby, direct skin contact, no direct skin contact, decoration) and don't define them, so the definitions above come from OEKO-TEX's STANDARD 100 page.
How the classes change the limits (examples from Annex 4)
- Formaldehyde: not detectable (n.d.) in Class 1; 75 mg/kg in Class 2; 150 in Class 3; 300 in Class 4 [2].
- pH: 4.0-7.5 for Classes 1 and 2; 4.0-9.0 for Classes 3 and 4 [1].
- Lead (extractable): 0.2 mg/kg for Class 1 and 1 mg/kg for Class 2 [3].
- PAHs: dibenzo[a,i]pyrene is 5 mg/kg for Class 1 and 10 mg/kg for Classes 2-4 [52].
- Not every limit varies by class. Carcinogenic dyes such as Direct Black 38 have one limit for all four classes: 50 mg/kg in Annex 4 and 20 in Annex 6 [16].
- Some entries apply to one class only. Annex 4's phthalate "sum without DINP" (1,000 mg/kg) applies only to Class 4. The other three classes show "n.a." for it [53].
I can lay out the full class-by-class limits for any substance group you're interested in.
How does a company get certified?
A company gets STANDARD 100 certified by applying in writing to an OEKO-TEX Institute it chooses and sending representative production samples. The institute tests every component against Annex 4 or Annex 6, a first-time applicant must also pass an on-site visit, and the applicant signs a Declaration of Conformity before the institute issues a one-year certificate. That certificate is also the licence to use the label. OEKO-TEX's website lists six steps: application, verification, definition and analytics, on-site visit, report, and certificate "for one year" (OEKO-TEX).
Approach: The datasets I can search only hold the STANDARD 100 limit-value tables, not the certification procedure. So the details below come from the STANDARD 100 standard document (Edition 01.2026, dated 03.03.2026) and OEKO-TEX's STANDARD 100 page (standard document).
The procedure (standard document, section 5.9 unless noted)
- Apply. Fill in OEKO-TEX's application form and send it to the institute you've chosen, with enough representative production samples for both documentation and testing. At this stage you choose Annex 4 or the stricter Annex 6, and that choice is printed on the certificate (section 5.2.1).
- Define the scope. The certificate scope sets out what is covered: product category, material composition, processed state (dyeing, printing, finishing) and accessories. Some things can't share one certificate, including:
- articles with different uses
- articles from different production stages
- own production and commission work
- organic and conventional cotton
- virgin and recycled material (section 4.3)
- Testing. The institute reviews your documents and samples, then sets the test programme based on the product, its materials, the Annex, the product class and your process information.
- Every component is tested.
- For a component under 1% of the article, the institute decides whether testing can be dropped, and that decision can't be contested.
- Components that already hold a valid STANDARD 100 certificate (or LEATHER STANDARD, for leather) are taken into account when setting the test scope. OEKO-TEX's web page says testing costs for the finished product are waived if every component is already certified (OEKO-TEX).
- Samples that smell of perfume, mould or faulty manufacture are excluded straight away and can't be certified.
- Test report and Declaration of Conformity. If the testing passes, you sign the Declaration of Conformity. This makes you solely responsible for keeping production consistent with the certified samples, and it accepts monitoring by OEKO-TEX and the institute (section 6.3).
- Certificate and label licence. The institute issues the certificate once it has all the documents. For a first certification, you can ask for the start date to be put back by up to three months after the test report. The licence to use the label starts when the certificate is handed over and ends as soon as the certificate expires or is withdrawn (sections 3.2, 6.5).
- On-site visit. This is required for a first certification and must be passed. It can happen shortly before or after the certificate is issued, and every company is visited at least once every three years after that.
- Sites holding an OEKO-TEX STeP certificate are exempt.
- The site must meet the exclusion criteria in Annex III.
- OEKO-TEX can also make unannounced visits at the company's cost. Refusing entry means the certificate is withdrawn (pp. 11-12).
Keeping the certificate
- Renewal: You can apply up to three months before expiry. The certificate number stays the same, and the new expiry date is exactly one year after the old one, so a late renewal doesn't buy extra time. If manufacturing hasn't changed, the institute normally sets a reduced test programme for the 1st, 2nd, 4th, 5th (and so on) renewals.
- Changes: You must tell the institute straight away about any change to materials, processes or recipes. Goods made differently from what was certified are treated as uncertified until the institute confirms they're covered. Washing or chemical cleaning after certification also ends a product's certified status (section 5.10).
- Supply-chain rules coming in:
- To renew, every company in the supply chain that does wet or chemical processing must hold its own STANDARD 100 certificate (section 5.7).
- For renewals, upstream certificates must come from the direct supplier, not a second-tier one (section 5.8).
- Both rules have a transition period to June 2027.
- Annual updates: OEKO-TEX normally publishes changes to the criteria in March. Stricter requirements usually apply from the following 1 June, though OEKO-TEX can bring them in immediately (section 5.2.4).
Special cases
- Biologically active or flame-retardant fibres and finishes: OEKO-TEX must assess and accept them first. Biologically active products are banned outright in baby articles and in articles that touch mucous membranes (sections 5.3-5.4).
- "Organic cotton" claims: The cotton must be OEKO-TEX ORGANIC COTTON certified and come with a transaction certificate (section 5.5).
- "Recycled" claims: At least 20% of the main material must be recycled, and it needs a separate certificate. Recycled material from unknown sources can only be certified in Classes II-IV; recycled PET bottles and food-grade material are the exception (section 5.6).
- Other products: Personal protective equipment and non-classic items such as furniture, pushchairs and bags are certified under the PPE and Special Articles supplements (section 5.2.3).
The standard itself says the label covers only harmful substances. It doesn't cover product safety, textile labelling, or SVHCs that aren't listed in Annex 4 or 6, and the applicant remains responsible for those legal requirements (section 3.1).