Certified, not just claimed
Anyone can say "sustainable." We'd rather show you the certificate. Every fabric we use has been tested or verified by an independent standard — and each one proves something different. Here's exactly what each certification covers, and what it doesn't.

OEKO-TEX® Standard 100
Used on: our bamboo viscose and activewear fabrics.

This is an independent test on the finished fabric, checking for harmful substances against strict international limits — things like certain chemical residues and heavy metals.

What it proves: the fabric has been tested and passed for harmful substances.
What it doesn't prove: organic fibre content, or how the garment was made. We tell you about those separately, fabric by fabric.

LENZING™ ECOVERO™

Used on: our ECOVERO™ viscose fabrics.

LENZING™ ECOVERO™ is a branded viscose fibre made from wood pulp sourced from certified or controlled sources, with Lenzing applying requirements around responsible wood sourcing and supply-chain traceability.

The fibre is produced using a process designed to have a lower environmental impact than conventional viscose.

What it proves: the fiber comes from Lenzing's verified sourcing and production system and meets the requirements of the ECOVERO™ fibre brand.What it doesn’t prove: that the finished garment is organic or chemical-free. That's why we look at the finished textile separately and use OEKO-TEX® STANDARD 100 where applicable.

OCS — Organic Content Standard
Used on: our organic cotton.

OCS verifies the percentage of organic fibre in a garment, tracked from farm to finished product through a chain of custody.

What it proves: the cotton is genuinely organic, and traceable.
What it doesn't prove: anything about processing chemicals or labour conditions. That's a different standard — GOTS — which we don't currently hold. We'd rather tell you that plainly than let "organic" imply more than it does.

 

REPREVE® We no longer use REPREVE® in our current collections.
Used on: our recycled nylon activewear.

REPREVE® is a traceable, branded recycled fibre, made largely from reclaimed plastic. Every batch carries a tracer so the recycled content can be verified.

What it proves: the nylon is genuinely recycled, and traceable back to its source.
What it doesn't prove: chemical safety on its own — that's why we also test our REPREVE® pieces to OEKO-TEX® Standard 100.

GRS — Global Recycled Standard
Used alongside REPREVE® on our recycled nylon.

GRS is a third-party chain-of-custody certification. It verifies recycled content and sets baseline environmental and social criteria at the certified facilities.

What it proves: recycled content, plus responsible handling at the certified sites.
What it doesn't prove: anything about the finished garment beyond the recycled input itself.

PFAS testing
Not a certification — an independent lab test.

We test our recycled nylon for PFAS, the "forever chemicals" found in some water- and stain-resistant finishes. Our results: not detected.

That means below the lab's detection limit — the most honest way we know to say it. We won't say "PFAS-free," because that implies a certainty testing can't actually give.

Real certifications, named plainly. That's what Trust What You Wear means to us — one fabric, one standard, at a time.

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