Silk Product Certifications Explained: OEKO-TEX, Sedex and ISO 9001

Why certifications matter for private label silk

For a private label program, the product is only half the decision — the documentation behind it is the other half. Retail buyers, importers, and marketplaces increasingly ask suppliers to prove that a product is tested for harmful substances, that the factory is audited for social and supply-chain compliance, and that quality is managed to a recognized standard. Certifications answer those questions with third-party evidence instead of a supplier’s own word, which speeds up onboarding and reduces risk for the brand. OlaSilk’s mulberry silk holds OEKO-TEX Standard 100, the company is a Sedex advanced member, and the factory is ISO 9001 certified.

• Tested-for-safety: OEKO-TEX Standard 100.
• Audited supply chain: Sedex (advanced member).
• Managed quality: factory ISO 9001.

OEKO-TEX Standard 100 — tested for harmful substances

OEKO-TEX Standard 100 is an independent testing and certification system for textiles. A certified material has been tested against a large catalogue of regulated and harmful substances and found within safe limits, including for items in close skin contact. For silk products worn against the skin or near the face — pillowcases, sleep masks, sleep caps, scarves, scrunchies — this is the certification retail buyers ask for most often, because it lets a brand make a credible "tested for harmful substances" claim. Note that OEKO-TEX Standard 100 is a safety certification, not an organic certification; the two are different things.

• Independent testing for harmful substances within safe limits.
• Covers skin-contact textiles — ideal for sleep and beauty silk.
• A safety standard, not an organic claim.

Sedex — social and supply-chain compliance

Sedex (the Supplier Ethical Data Exchange) is one of the largest platforms for managing and sharing responsible-sourcing data. Membership and the associated SMETA audit framework let buyers see how a supplier performs on labour standards, health and safety, environment, and business ethics. Large retailers and importers often require their suppliers to be on Sedex before placing orders, so an existing membership removes a common onboarding hurdle. OlaSilk holds Sedex advanced membership.

• Shares responsible-sourcing data buyers can review.
• Built around the SMETA audit (labour, H&S, environment, ethics).
• Frequently required by larger retailers and importers.

ISO 9001 — a managed quality system

ISO 9001 is the international standard for a quality management system. A certified factory has documented, repeatable processes for how it controls quality — from how orders and specifications are handled to how problems are tracked and corrected. For a brand placing a custom order, ISO 9001 is a signal that quality is run as a system rather than left to chance, which supports more consistent results across repeat production runs. OlaSilk’s factory is ISO 9001 certified.

• A documented, repeatable quality-management system.
• Supports consistency across repeat production runs.
• A factory-level standard, separate from product testing.

How to use certifications when you source

Treat certifications as part of your sourcing checklist. Ask the supplier which certifications apply to the specific material and product you are ordering, request the supporting documents, and confirm they are current. Match the certification to the claim you intend to make at retail — for example, use OEKO-TEX to support a "tested for harmful substances" message, not an "organic" one. OlaSilk can share the relevant certification documents during sampling so your team can verify them before a production order.

• Request the documents and confirm they are current.
• Match each certification to the exact retail claim you will make.
• Verify during sampling, before committing to bulk.

Silk product certifications at a glance

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