Which substances a textile certificate covers
Sep 20, 2026
Short answer: Most certificates test the finished fabric for chemical residues, such as heavy metals, dyes and preservatives. The limits are stricter for clothing that touches the skin than for clothing worn as an outer layer.
The groups of substances
Testing typically covers heavy metals, formaldehyde, certain dyes and pesticide residues. Each group has its own limits, and the list can change as new knowledge emerges. This also applies to socks for men, which are worn every day and sit close to the skin for many hours.
Why these substances
The substances can enter at different stages. Pesticides may come from growing the fibres, dyes and heavy metals from dyeing, and formaldehyde from treatments meant to make fabric crease-free or keep its shape. The test looks at what remains in the finished item, not at what was used along the way.
Stricter limits close to the skin
Clothing worn directly against the skin is tested to stricter limits than an outer layer. The idea is that skin and sweat can draw more out of the fabric when contact is close and long. That is why limits are strictest for items like a bamboo tank top for men and underwear worn all day.
What is tested in practice
Samples from each production batch go to a laboratory, and the result applies to that batch. The lab measures each substance and compares it with the limits. If everything is below, the batch passes. This also applies to bamboo joggers for men, where different parts may be tested separately.
A limit is not zero
A substance below the limit is not necessarily absent. It means the amount is low enough to be judged acceptable for that type of clothing. This matters because a certificate is often read as a promise that there are no chemicals in the fabric at all.
Who sets the rules
The limits are set by the organisations that issue the certificates. On top of that, the EU has its own laws on chemicals in consumer goods, which apply regardless of any certificate. A certificate can be stricter than the law, but never looser, if the item is to be sold legally in the EU.
Wash new clothing before wearing
Whatever the certificate, it is a good habit to wash new clothing before you wear it. Washing removes dust from transport and storage and any residue from finishing. This matters most for clothing worn close to the skin. If you have sensitive skin or lasting discomfort, talk to your doctor.
How to use the information
Look for the certificate number on the product page or hang tag and look it up with the issuer. You can then see what kind of test was done and whether it is valid. Use it as one piece of information among several, alongside the care label and your own feel for the fabric.
Frequently asked questions
Does a certificate mean the fabric is chemical-free
No, it means certain substances are below a limit. All clothing contains chemicals in some form, including the fibres themselves.
Who decides the limits
Independent organisations, and the EU also has its own legislation. The law always applies, while a certificate can add stricter requirements on top.
Can you see the test
The certificate number can usually be looked up with the issuer. There you can see who holds the certificate and which products it covers.
