UVA, UVB and Broad Spectrum Meaning Index

Claim status: defined by a scheme. This index is defined by Natural Sun Care's stated audit method. It does not create a legal definition of UVA, UVB or broad spectrum, and it does not assess sunscreen products.

What this index measures

The UVA, UVB and Broad Spectrum Meaning Index records the clarity and traceability of public statements about three commonly used sunscreen terms. Its subject is the language surrounding those terms in UK-facing material, rather than the performance of a particular product, a UV filter or a person's protection in sunlight. Each edition uses the same source categories, inclusion rules and reporting fields so that a later result can be compared with an earlier one.

UVA and UVB describe parts of ultraviolet radiation, but they are not interchangeable labels. Broad spectrum is a consumer-facing description whose useful meaning depends on the standard, regulatory framework or testing context being invoked. A statement can be understandable while still failing to say what it rests on. It can also refer to a technical requirement without explaining it for a non-specialist reader. The index separates these situations.

The register is designed to answer a narrower question than "does sunscreen work?" It asks whether a source makes it possible to establish: which term is being used; whether the source distinguishes UVA from UVB; whether broad-spectrum language is connected to a stated basis; and whether the reader can identify the authority behind the statement. That is a record of claim clarity and source attribution, not a verdict on an individual formulation.

No index result is published in this first entry because the brief supplies no audited source set, observation date or completed count. Reporting a number before those inputs exist would turn a repeatable method into an invented result. This page therefore fixes the method that a future edition must follow.

How each edition is built

Each edition begins with a fixed observation date and a preserved list of included sources. The source list is divided by role, not by popularity: UK regulatory material, guidance from named public-health or medical bodies, standards or test-method material where publicly stated, and explanatory material that claims a UK relevance. A source is included only if it contains a substantive statement about UVA, UVB or broad spectrum. A passing reference or an image without explanatory text is recorded as out of scope.

For every included source, the audit records the exact term or terms addressed, the publication or revision date if supplied, the named authority if supplied, and whether the statement identifies a test, standard, regulation or other basis. It also records whether the wording keeps distinct things distinct. For example, a source that says UV radiation can harm skin but does not distinguish UVA from UVB cannot count as a definition record for both terms.

The reported index is built from counts, not editorial weighting. For each topic, the edition reports the number of included sources that meet the relevant documented conditions alongside the total number of included sources eligible for that topic. The traceability record is reported in the same way. The edition also lists exclusions and the reason for each exclusion, so a reader can see what was not counted and why.

A source can be clear yet have no named basis. In that event, its clarity is recorded separately from its traceability. A source can name a regulatory or testing basis but explain it poorly. That too is recorded separately. This prevents the index from treating a citation as a substitute for a meaningful explanation, or a smooth explanation as proof of regulatory status.

Decision rule for coding UVA, UVB and broad spectrum

The coding rule is intentionally narrow. It does not infer an unstated meaning from a familiar phrase, a product image, a star symbol or an acronym. Auditors assess the words that the source makes available and preserve a quotation or page record for internal verification. A claim is recorded only at the level supported by that text.

The rule does not award credit for implication. "Protects from the sun" does not explain UVA, UVB or broad spectrum. "UVA/UVB protection" distinguishes neither term unless the source supplies a distinction in its own text. "Broad spectrum" without an accompanying explanation can be recorded as usage of the phrase, but not as an explanation record. These restraints matter because an index of language can otherwise reward repetition rather than clarity.

When a source uses a term differently in separate places, each substantive statement is preserved, but the source receives one topic-level record based on whether it contains a qualifying explanation anywhere within the audited material. Contradictions are not averaged away. They are noted as a consistency issue in the edition narrative and the source is marked for review.

What the index can say, and what it cannot

A completed edition can show how often the predefined source set gives a reader a distinct explanation of UVA, UVB and broad spectrum, and how often those explanations identify their stated basis. It can show a change in those counts over time if the same inclusion rules are retained. It can also show where terms are commonly used without sufficient explanation or without a traceable basis.

It cannot establish that a sunscreen provides adequate protection. Protection depends on the finished product, its tested performance, its labelled instructions and the applicable regulatory framework. The index does not inspect products, test skin exposure, evaluate application quantity, compare formulations or score brands. It does not convert broad-spectrum wording into a universal protection standard.

The index also cannot decide whether a source's technical explanation is scientifically complete. Its primary question is whether the required elements are present and attributable. A short public-health explanation may be appropriate for its audience while lacking the detail of a technical standard. Conversely, a technical document may offer a defined test basis without explaining everyday terminology. Both can be accurately recorded without treating them as interchangeable documents.

UK relevance is important, but it is not a claim that all terminology is globally harmonised. Where a source clearly identifies another jurisdiction's framework, that framework is recorded as such rather than silently treated as UK law. The index does not translate foreign labelling systems into UK requirements. It records the source's stated scope and excludes material whose scope cannot be determined where that uncertainty would make comparison misleading.

Sources, authority and claim status

The index uses four claim-status categories to keep authority visible. Defined in law is reserved for a term or requirement that a relevant legal instrument itself defines or clearly establishes. Defined by a scheme applies where a named standard, testing framework, certification scheme or this index's documented method supplies the definition. Undefined applies where the phrase is used but no applicable definition is supplied by the source under review. Unsupported applies where a source makes a factual assertion but does not provide enough information for the assertion's stated basis to be identified.

These statuses concern the individual claim being audited, not the reputation of the organisation that published it. A public body can publish a concise explanation that does not define every term. A technical body can define a measurement without making a consumer-language claim. The coding therefore attaches to the statement and its stated basis, not to an institution as a whole.

For context, the NHS describes UVA and UVB as types of ultraviolet radiation in its public information on sun safety. That provides a named institutional source for a general distinction, but it does not by itself establish every regulatory condition connected with sunscreen claims. Regulatory requirements and test-method questions must be traced to the relevant legal or standards material when an edition reports them.

Every future edition must publish its observation date, source list, exclusions, coding notes and any changes to the method. If the method changes, the publication must say so plainly and must not present the new result as directly comparable with a prior edition without a bridge note. Consistency is what gives a recurring index its value; a number without a stable method is only a snapshot.

Publication cycle and correction policy

This is a recurring index, but no release frequency is asserted until a dated publication schedule is established. A new edition may be issued after a material change in UK-facing regulatory guidance, a relevant standard or test-method publication, or the audited source set. It may also be issued as a routine review using the same rules. Each edition must identify whether it is a routine review, a change-led review or a correction.

Corrections distinguish between errors in transcription, errors in coding and later changes to a source. A transcription error concerns what the audit recorded from a source at the observation date. A coding error concerns whether the stated decision rule was applied correctly. A later source change does not alter a historical edition silently: it belongs in the next edition, unless the earlier page was misdated or misidentified.

When an entry is corrected, the index should retain the original publication date, state the correction date and describe the nature of the correction. If a corrected count changes an index result, the revised record must identify that change rather than replacing the earlier number without explanation. This makes the index usable for journalists and researchers who need to understand which version they are citing.

No value is retroactively estimated from sources that were not included at the stated observation date. No missing date is invented. No unnamed standard is assumed. The same restraint applies to a source that has disappeared: its former content cannot be reconstructed from memory. Where verification is no longer possible, the edition records the limitation and does not make a stronger claim than the surviving evidence permits.

Limits of this index

This index does not cover product selection, label-reading steps, application practice, time outdoors, swimming, sweating, reapplication, storage or expiry. It does not cover the safety, environmental effects or chemistry of particular UV filters. It does not decide whether mineral or organic filters are preferable, and it does not assess skin conditions, children's needs or individual medical circumstances.

It is not a substitute for legal advice, medical advice, laboratory testing or a regulatory compliance assessment. It does not apply a UK result to a product sold under another jurisdiction's rules merely because the same words appear on packaging or advertising. It also does not measure public understanding, search popularity, advertising reach or the prevalence of a term across every possible source.

The present entry is a method publication only. It has no completed audit population, no observation date and no numerical index output. Readers should not cite it as evidence that any named term is more or less clearly defined across UK-facing sources. Its current function is to state the rules that will govern a future, auditable result.