The requirement, in two places
Substantiation for a sun protection claim comes from two directions at once, and it is worth separating them because they impose slightly different obligations.
Cosmetics law. A claim about a cosmetic product must comply with the common criteria for cosmetic claims, which include that a claim is supported by adequate and verifiable evidence. The evidence supporting effects claimed forms part of the product information file, which the responsible person must keep and make available to enforcement authorities.
Advertising rules. The advertising codes require that objective claims are capable of substantiation and that documentary evidence is held before the claim is published. The Advertising Standards Authority may ask to see it, and an inability to produce it promptly is itself a problem.
The two overlap heavily and are not identical. A claim can satisfy one and cause difficulty under the other, most often because the advertising assessment considers the impression created rather than the wording alone.
What adequate means
Four tests do most of the work, and a claim that passes all four is usually defensible.
Does the evidence relate to the finished product? A study of an ingredient supports a claim about that ingredient. Claims are made about products, and the finished formulation is what a consumer buys.
Does it support the claim as understood? The relevant proposition is the one a consumer takes from the wording, not the narrower one a technical file might address. This is the point at which most claims fail.
Does it cover every element? A claim naming a duration requires evidence about that duration. A claim naming a population requires evidence about that population. A comparative requires evidence about the comparison actually made.
Is it verifiable? Someone else must be able to check the basis of the claim. That means a documented method, identifiable conditions and a retained report rather than an assertion that testing was done.
What the file holds for a sun protection product
The product information file is a document set held by the responsible person and kept available for a period specified by the regulation. Its contents cover far more than claims, including the safety assessment, and the claims evidence sits within it.
For a sun protection product the claims evidence typically includes the in vivo sun protection factor report, the in vitro ultraviolet A report, water resistance testing where a resistance claim is made, tolerance or dermatological assessment reports where tolerance claims are made, stability and compatibility data underpinning the durability marking, and documentation supporting any additional claims such as environmental ones.
The general point is that each distinct claim on the pack should be traceable to something in the file. A pack carrying eight claims and a file supporting three is the ordinary form of a substantiation failure.
| Claim | Evidence required |
|---|---|
| The protection factor | In vivo determination to a recognised method, for the finished product |
| The circled UVA mark | In vitro UVA determination and critical wavelength against the thresholds |
| Water resistant | Immersion testing to a recognised method, with the tested sequence stated |
| Suitable for sensitive skin | Tolerance assessment relating to that claim and that population |
| Suitable from a stated age | A safety assessment addressing that user |
| An environmental claim | Substantiation under consumer protection rules and the Green Claims Code |
| A comparative claim | Evidence for the comparison actually made, like for like |
Framework of this publication. It describes how published rules and guidance fit together and is not a measurement, a survey or a study.
Who holds it
The responsible person. For products placed on the Great Britain market that person must be established in Great Britain, and their name and address appear on the pack. Their role and obligations are set out in the responsible person and the product information file.
The practical consequence for anybody in the chain is that responsibility does not distribute itself comfortably. A distributor who changes the labelling, a retailer who writes its own claims and a business that puts its own name on a product manufactured by somebody else are all taking on obligations, and the assumption that the manufacturer holds everything is frequently wrong.
Before, not after
The sequencing requirement is the one most often missed. The advertising codes require that evidence is held before the claim is made, and assembling a file in response to a complaint does not satisfy it.
There is a practical reason beyond the formal one. Evidence assembled after the fact is assembled to fit the claim, and it tends to be evidence about a related proposition rather than the one at issue. Evidence gathered first tends to shape the claim to what it supports, which is the correct order of operations and produces better wording.
The common failure patterns
Ingredient evidence for a product claim. The single most common pattern across cosmetic claims generally.
Perception data presented as measurement. A proportion of a panel agreeing with a statement records opinion. Presenting it so that a physical effect is inferred changes the claim.
Evidence for a narrower proposition. A study under laboratory conditions supporting a claim about use, or a determination on one variant supporting a claim about a range.
A superseded method. A report to an earlier version of a standard cited as compliance with the current one.
The unqualified absolute. Wording such as complete, total or proof leaves nothing to evidence against, which is why claims of that character appear so often in the prohibited list rather than the restricted one.
Auditing a pack against a file
The practical exercise that reveals substantiation problems is unglamorous and takes an afternoon. List every claim on the pack, including the ones that do not look like claims, then find the document that supports each one.
The list is always longer than expected. The protection factor and the ultraviolet A mark are obvious. Less obvious are the product name, which frequently contains a claim; the imagery, which can carry an implication; the on-pack instructions, which state conditions; the descriptive adjectives; any symbol or third party mark; and the retail listing copy that travels with the product through the trade.
Against that list, the file often supports the technical determinations comprehensively and the descriptive claims not at all. That is the ordinary shape of the problem: businesses invest heavily in the evidence for the number, because the number is expensive and obviously technical, and treat the adjectives as copy rather than as claims.
The corrective is to treat every element that a consumer could take as a statement about the product as a claim requiring support, and to write the copy after the evidence rather than commissioning evidence to defend the copy.
Why this matters more in this category
Sun protection claims are unusual among cosmetic claims in that a consumer may rely on them in a way that has consequences. A claim about texture that turns out to be optimistic is a disappointment. A claim about duration that turns out to be optimistic changes behaviour.
That is not a legal distinction and it does not change the requirements. It is, however, the reason enforcement bodies and public health organisations take a closer interest in this category than in most, and the reason a business writing sun protection copy should treat substantiation as a design constraint rather than as a compliance step at the end.
Ranges, variants and the reuse problem
Products are rarely sold alone. A range shares a name, an identity and usually a marketing narrative, while differing in format, fragrance, texture, tint or pack. That creates a recurring substantiation question: how far does evidence for one variant reach?
The starting position is that a determination relates to the formulation tested. A change that could affect the ultraviolet filter system, the film formed on skin, or the way the product spreads is a change to the thing measured. Format changes are the obvious case, since a spray, a lotion and a stick do not form the same film. Tint, fragrance and preservative changes are less obvious and are not automatically immaterial.
The pattern that causes problems is a range built out from a single tested variant, with the figure carried across because the formulations are described internally as similar. Similar is not a defined term and it is not a substitute for a determination. Where a business does rely on read-across between variants, the reasoning has to be documented in the file and has to be capable of being explained.
The same applies over time. A formulation reworked for supply reasons, a filter substituted because of availability, or a manufacturing site changed, are all points at which the question arises again. A test report is dated, and so is the formulation it relates to.
What to take from this
Evidence must exist before the claim, relate to the finished product, support the claim as consumers understand it, cover every element including comparisons and durations, and be verifiable. It sits in the product information file with the responsible person, and every claim on the pack should be traceable to something in it.