iiRDS Selector: FragmentSelector and RangeSelector for parts of files

Example

A machine builder holds a 180-page PDF operating manual for a CNC lathe, released years ago and not scheduled for rewriting. To make it useful in the service portal, the team defines three topics: "Lockout before maintenance" (pages 22 to 24), "Changing the chuck jaws" (pages 61 to 66) and "Alarm list" (pages 140 to 158). Each topic has a rendition pointing to the same PDF file, narrowed by a RangeSelector with page= start and end values. Each topic carries its own lifecycle phase and audience metadata. The PDF is not altered, and a machine display can now link straight to the alarm list.

How it applies

Technical documentation

Selectors decouple granularity from file structure. An HTML page with many error codes can stay one file, while a FragmentSelector with an XPointer or #id value lets each code be delivered as its own Fragment with metadata. The page itself can remain a topic with a plain rendition, so both levels of granularity coexist on one file.

Migration

For legacy PDFs, range selectors are the shortest route to fine-grained delivery: define units for chapters, point them at page ranges, and keep the original file. Mind the boundary convention: in the specification's page-range example, the range includes the start page but not the end page, so a chapter ending on page 24 needs page=25 as its end value.

MedTech

When approved instructions for use exist as a fixed PDF, selectors can expose sections such as warnings or cleaning instructions as separate units without changing the approved file. Selectors do not validate content; they only make a part addressable. Note that iiRDS/H packages do not allow selectors at all, so handover packages deliver such documents whole.

AI and retrieval

Selectors give retrieval systems chunk boundaries set by authors rather than by token counts, plus exact anchors for citations. An assistant can answer from the "Alarm list" unit and deep-link to the PDF page, instead of pointing a technician at a whole manual. Keep the selector values with each indexed chunk so the link can be rebuilt.

FragmentSelector vs. RangeSelector vs. Fragment

Concept	What it selects or is	Key properties
FragmentSelector	One identifier; a range only if the standard allows it (for example t=90,210)	rdf:value, dcterms:conformsTo
RangeSelector	Everything between a start and an end identifier	iirds:has-start-selector, iirds:has-end-selector
Fragment	An information unit that needs context — not a selector	IRI, metadata, renditions

A Fragment is about meaning; a selector is about location. The two often appear together, because a small unit frequently lives inside a larger file.

In RDF

A topic delivered from a page range of a PDF, and a fragment selected from an XML file by XPointer. Shown in Turtle for readability — inside a package, metadata.rdf is written in RDF/XML.

@prefix iirds: <http://iirds.tekom.de/iirds#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix dcterms: <http://purl.org/dc/terms/> .

<https://example.com/iirds/alarm-list> a iirds:Topic ;
    iirds:has-rendition [
        a iirds:Rendition ;
        iirds:format "application/pdf" ;
        iirds:source "content/pdf/lathe-operating-manual.pdf" ;
        iirds:has-selector [
            a iirds:RangeSelector ;
            iirds:has-start-selector [
                a iirds:FragmentSelector ;
                dcterms:conformsTo <http://tools.ietf.org/rfc/rfc3778> ;
                rdf:value "page=140"
            ] ;
            iirds:has-end-selector [
                a iirds:FragmentSelector ;
                dcterms:conformsTo <http://tools.ietf.org/rfc/rfc3778> ;
                rdf:value "page=159"
            ]
        ]
    ] .

<https://example.com/iirds/alarm-e17> a iirds:Fragment ;
    iirds:has-rendition [
        a iirds:Rendition ;
        iirds:format "application/xml" ;
        iirds:source "content/xml/alarms.xml" ;
        iirds:has-selector [
            a iirds:FragmentSelector ;
            dcterms:conformsTo <http://tools.ietf.org/rfc/rfc3023> ;
            rdf:value "xpointer(id('alarm-e17'))"
        ]
    ] .

In topic-based authoring and modular architectures

In native topic-based authoring, each topic is usually its own file, so selectors are rarely needed; reuse happens in the source, for example through a DITA content reference. Selectors matter where published output bundles many modules into one file — a merged PDF, a single-page HTML manual, a training video — and each module should still be delivered with its own metadata. In modular delivery architectures, a selector is the bridge between monolithic deliverables and granular consumption: the portal, the machine display or the retrieval index works with units, while the package keeps one physical file. Stable anchors, such as element IDs rather than page numbers, make selectors survive re-publication better.