UV400 and Lens Darkness

Define What UV400 Claims

UV400 is commonly used in eyewear to describe UV protection extending to a wavelength of 400 nanometres. It is not a visible-darkness rating, a polarizing specification or a standalone certification mark. The number identifies a wavelength boundary; the claim also needs a defined limit on how much UV may pass through.

Do not translate UV400 automatically into zero transmission at every wavelength, or into a universal laboratory pass criterion. Ask which method, wavelength range and acceptance limits support the proposed wording. A lens sticker without that basis is a claim awaiting verification, not proof of protection.

Understand the Wavelength Boundary

The following wavelength definitions come from the World Health Organization. They describe radiation bands, not eyewear performance limits.

A UV380 statement does not by itself establish performance between 380 and 400 nm. That gap in the wording is a reason to request data, not proof that the lens necessarily transmits all radiation in that interval. Likewise, an unlabelled lens is not automatically a failing lens; its performance is simply not established by a label.

Separate Darkness, Polarization and UV

Visible light transmission, often abbreviated VLT, describes the visible light passing through a lens under the stated measurement method. UV transmission describes a different spectral region. A darker view therefore cannot establish stronger UV protection. ZEISS explains the distinction between tint and UV protection. Request separate visible and UV transmission results for the lens being supplied.

Filter categories are not a universal higher-is-better scale. Select the lens for the intended light conditions, use restrictions and market requirements. Do not advertise a dark or polarized lens as suitable for night use merely because its UV performance is documented.

Read the Report, Including Its Scope

Request spectral transmission evidence extending through 400 nm when that is the claim you intend to make. The report should identify the measurement method, wavelength coverage, acceptance limits, laboratory, date and tested sample. Ask for numerical results or a suitable spectral presentation, not just an unexplained pass stamp.

Match the sample to the finished lens: material, tint, mirror and other treatments, geometry where relevant, and the production reference. A grey lens report does not automatically cover an unrelated rose lens. A report may cover a documented group of variants, but the basis must be explicit and include the ordered configuration.

Keep a claim-to-variant register for the range. Mark which variants have supporting evidence, which rely on an accepted grouping, and which remain unverified. Recheck the position when the lens supplier, material or coating changes. This is more useful than filing a certificate under the frame model alone.

Keep Regulatory Claims Within Their Scope

As checked on 18 October 2026, the ISO public catalogue lists ISO 12312-1:2022 and Amendment 1:2026. Its scope concerns general-use sunglasses, not all specific-sport eye protectors. Confirm the applicable destination-market adoption and requirements; a catalogue listing is not a product approval.

In the EU, Regulation (EU) 2016/425 places the risk of eye damage from sunlight, except direct observation of the sun, in Category I. This does not determine the route for every product with additional protective claims. The manufacturer must address the applicable conformity assessment, technical documentation, declaration and marking obligations; a UV test report alone is not the complete conformity file.

In the US, 21 CFR 801.410 addresses impact-resistant lenses. It is not a UV400 certification or a specific-sport protective rating. Do not use lens impact evidence as the basis for a UV claim. Confirm the full set of applicable obligations for the product, protective claims and destination market before placing it on the market.

Approve Claims Per Variant Before Ordering

Approve exact packaging and product-page wording against the evidence. Avoid an entire-range UV400 statement unless the supporting scope demonstrably covers the entire range. Base approval on reports covering the supplied WORLUX lens configuration, with material data used as supporting information.

• Identify the model and every lens colourway to be supplied.
• Record the UV claim, test basis and supporting report reference.
• Record visible transmission, filter category and applicable use warnings separately.
• Keep polarization and mechanical-performance claims linked to their own evidence.
• Agree change notification and the process for closing documentation gaps before claim approval.

For a quotation, state the intended market and the claims needed for each lens configuration. Consult ordering terms; the quotation confirms per-model and per-colour totals and the applicable schedule. Commercial confirmation and technical claim approval are separate steps, and both should be complete before the order specification is finalised.