A standalone symbol still needs its own glossary

A label crowded with the same sentence repeated in a dozen languages is one of the oldest problems in device packaging, and both major regulators have opened the same door to relieve it: let a standardized symbol stand in for the sentence. 21 CFR 801.15(c) and MDR/IVDR Annex I both let a device's labeling carry a symbol instead of adjacent explanatory text, provided the symbol comes from a recognized standard and is used the way that standard specifies. Neither regulator treats that as the end of the obligation. A symbol used without its own explanatory text still has to be explained somewhere the user can actually find it — a symbols glossary, on the label or in the labeling, naming what each mark on the device means. A device that adopts the standardized symbols and skips the glossary has taken the shortcut the rule offers and left out the condition attached to it.

Two regulators, the same swap

21 CFR 801.15(c)(1) lets a symbol appear without adjacent explanatory text if it's established in a standard FDA recognizes under section 514(c) of the FD&C Act and used according to that recognition's own specifications. MDR Annex I 23.1(h) and IVDR Annex I 20.1(h) run the same idea from the other direction: where appropriate, labeling information “shall take the form of internationally recognised symbols,” with any symbol or identification colour conforming to the harmonised standards or common specifications that govern it. Both rules ultimately point at the same document doing the underlying work — ISO 15223-1:2021, harmonised to MDR and IVDR by Commission Implementing Decision 2022/6, and separately recognized by FDA under its own standards-recognition program.

The condition the swap comes with

FDA's version of the condition is explicit text, not a best-practice add-on: a stand-alone symbol has to be explained in a paper or electronic symbols glossary included in the device's labeling, and the package itself has to carry a prominent, conspicuous statement telling the user where that glossary is. The EU's default runs the opposite direction on the surface — because EN ISO 15223-1:2021 is itself a harmonised standard, its own symbols don't always need re-explaining in the instructions for use when the intended user is a professional who can be expected to already recognize them. That relief narrows fast: the moment a device's intended user includes a layperson, the symbols need explaining regardless, which lands the EU back at the same glossary duty FDA treats as the baseline rule rather than the exception.

Using the standard's symbol on the standard's terms

Both regimes tie the shortcut to the symbol being used according to the specifications set out in whatever recognized it — the standard itself, or FDA's own recognition of it. A manufacturer can't take a shape out of ISO 15223-1 and repurpose its meaning, and can't invent an original pictogram and claim the same stand-alone exemption an established, recognized standard earns on its own. FDA's rule adds one more layer on top: the manufacturer still has to independently judge that the symbol is likely to be read and understood by the ordinary user under customary conditions of purchase and use, under section 502(c) of the Act. A recognized standard is the necessary basis for the shortcut. It isn't a substitute for the readability judgment the manufacturer still owns underneath it.

A glossary is a controlled document, not a footnote

Because the glossary is doing the job the missing explanatory text would otherwise do, it has to travel with the device the way any other labeling element does. It has to reflect the same edition of the standard the symbols were actually drawn from — ISO 15223-1 has been revised before, and a symbol's exact graphic or defined meaning isn't guaranteed identical across editions — and it has to be genuinely locatable, not merely present somewhere inside a long instructions-for-use document. A device whose labeling carries pictograms from one edition of the standard while its glossary is still keyed to an older one has the same version-drift problem this blog has already tracked for any other mapped source, just running through a symbols table instead of a citation.

Where this meets the rest of the file

The symbol-for-text swap is a narrower question than the one the instructions for use themselves have to answer under 21 CFR 801.5 or MDR Annex I Section 23.4 — a symbols glossary can satisfy the label's own completeness, and still leave the underlying IFU content test unanswered, because the two sit on different parts of the labeling and neither substitutes for the other. And where a device relies on electronic delivery for its full instructions, the symbol pointing a user toward them is doing real work of its own — the same electronic-access obligation this blog has already covered still has to be labeled clearly, glossary or no glossary.

A labeling-symbols glossary built around this structure — the recognized-standard basis, the edition it was drawn from, and the lay-use trigger that reintroduces the explanation requirement — is previewed in the launch catalog. If your program's symbol key runs differently, the shelf takes that correction directly.