At DrawingHub, our position is direct. The title block is the metadata. Almost everything an operations team needs to find, trust, and act on a drawing already exists there. The job is not to invent new metadata. The job is to read what is already on the page, reliably, across forty years of vendor templates, and to tell you honestly how much of that data your existing system can actually see.
That is also why every DrawingHub engagement starts the same way. Before extraction volume, before EDMS integration, before anyone signs anything, we run a findability report. The first page of that report is always the title block. This piece explains why.
The boring square is busier than it looks
Australian engineering drawings live under two overlapping standards: AS 1100 (the Australian standard for technical drawing) and ISO 7200 (the international standard for title-block data fields). AS 1100.101 — approved on 25 August 1992 and published on 16 November 1992 — mandates ten essential components on every compliant title block: company name, drawing title, drawing number, revision number and date, scale, author, date created, checked-by, sheet number, and a reference to the drawing standard itself. ISO 7200:2004, published 15 February 2004 to replace its 1984 first edition, trims that list to eight strictly mandatory fields and adds eleven more as optional.
Most Australian mining and heavy-industry organisations follow AS 1100 in principle. In practice, vendor and contractor templates blend the two, add half a dozen client-specific fields, and silently mutate over the lifetime of a long-running asset. A title block on a 2003 substation drawing from one contractor does not look like a title block on a 2019 conveyor drawing from another, even when they describe equipment fifty metres apart on the same site.
That blend is not a problem in itself. AS 1100 was designed to be a floor, not a ceiling. The problem is what happens when an organisation tries to find drawings ten or fifteen years later, and discovers that the data their search depends on lives in pixels, not fields. And it is compounded by a quieter fact: the standards themselves stopped moving long ago.
The standards stopped moving decades ago
The reason title blocks drift is not only that vendors improvise. It is that the documents defining them were written for a drawing office, not a search index, and then largely left alone. The lineage is older than most of the assets it governs.
| Standard | First issued | Last technical revision | Status in 2026 |
|---|---|---|---|
| AS CZ1 — Australian drawing lineage | 1941 | 1973 | Superseded — origin of the Australian title-block tradition |
| AS 1100.101 — Technical drawing, general principles | 16 November 1992 | 1992 (reconfirmed 2014, no technical change) | Current edition — unchanged for over three decades |
| ISO 7200 — Title-block data fields | 1984 (first edition) | 15 February 2004 (second edition) | Current edition — unchanged for over two decades |
| ISO 55001 — Asset management system requirements | 2014 (first edition) | July 2024 (second edition) | Current edition — actively maintained |
Read the table as one sentence. The rules that decide how a drawing is identified — AS 1100.101 and ISO 7200 — were fixed in 1992 and 2004 respectively. AS 1100.101 has not had a technical revision in over thirty years; it was merely reconfirmed in 2014. ISO 7200 has not moved since 2004. Both predate the modern EDMS, predate large-scale scanning programmes, and predate machine retrieval entirely.
Meanwhile the standard that governs how this data is actually used in operations — ISO 55001, asset management — was modernised in 2024. The expectations sitting on top of the title block moved on by thirty years. The definition of the title block did not. That gap is not a vendor problem; it is a structural one, and every organisation inherits it.
None of this makes the old standards wrong. AS 1100.101 and ISO 7200 still describe a sound floor. They were simply never asked to be machine-readable, never asked to absorb forty years of contractor variation, and never updated when retrieval — not draughting — became the job that mattered.
What is actually in a real title block
A worked example. An underground electrical drawing from an Australian coal operation, the kind of drawing a frontline electrician might pull up before isolating a piece of equipment, typically carries something like this in its title-block region.
| Field | Example content | Source |
|---|---|---|
| Drawing number | SITE-DRW-ELE-115053 | AS 1100 / ISO 7200 mandatory |
| Vendor / supplier number | D15-MJE-063 | Vendor template field |
| EPCM contract number | MJE J3353 | Project-specific |
| Previous drawing number | (legacy migration trace) | Operational addition |
| Revision number | 3 | AS 1100 / ISO 7200 mandatory |
| Revision status | As Built | Operational addition |
| Sheet descriptor | 1 to 11 | AS 1100 mandatory |
| Title (line 1) — site | Underground Coal Operation | AS 1100 mandatory |
| Title (line 2) — area | Goaf Dewatering | Continuation |
| Title (line 3) — system | Power Distribution | Continuation |
| Title (line 4) — type | Single Line Schematic | Continuation |
| Discipline / area | Underground / Mine Site Support | Operational addition |
| Revision notes | REV1: L&P test circuit details on Sheet 3. REV2: As Built. REV3: Added relay contacts K306 and K337. | History block |
Three observations from a single drawing.
First. The drawing carries five different identifiers. The standard drawing number, the vendor's internal number, the EPCM contractor's job number, a previous drawing number from before a system migration, and an internal plant tag. Any one of them might be the search term someone types into the EDMS. None of them is reliably unique on its own.
Second. The title is split across hierarchical lines, and the order is not arbitrary: line 1 is the site, line 2 the area, line 3 the system, line 4 the type. Read together rather than as a flat string, those lines resolve to a functional location — the same Site → Area → System → Type structure asset and maintenance teams already use to index equipment — tying the drawing to the physical asset it documents. Generic OCR run across that region returns a 150-character run-on string instead. A search for "single line schematic" against that string will hit. A search for "single-line schematic" (with the hyphen) will miss. The hierarchy is there. It is not indexed.
Third. The revision history is not "Rev 3". It is a three-line narrative explaining what changed at each revision, including a strike-out overwritten later. Read by a human in twenty seconds. Read by a naive OCR pipeline as noise.
This is what the title block actually contains. It is not a polite list of fields. It is the entire history of a piece of plant, compressed into roughly 1% of the drawing's surface area.
The 88% problem
A DrawingHub customer, an Electrical Engineering Manager at a large Australian operation, described the state of their drawing library after a recent EDMS migration like this:
“After migrating to our Engineering Drawing Management System, our engineers and coordinators couldn't find the drawings they were searching for. We found that 88% of the existing system metadata was generic and unsearchable. We are now at close to 100% metadata extracted from our drawings. This rebuilt confidence in the system without compromising governance.”
That ratio, 88% generic and 12% useful, is not unusual. It is the rule, not the exception, for organisations that migrated paper or scanned PDFs into an EDMS in the 2000s and 2010s, when "metadata entry" meant a contractor typing the drawing number into a single field and ticking "done".
The library was uploaded. The library was technically searchable. The library was not findable.
The distinction matters. An EDMS report will tell you the percentage of drawings uploaded. It will not tell you the percentage of drawings discoverable by the right person, looking for the right thing, under time pressure. That second number is what costs you in safety, in downtime, in audit findings, and in the slow erosion of trust that ends with engineers maintaining their own folders on their own laptops because the official system "doesn't work".
The title block is where that gap lives.
Why title blocks defeat naive OCR
If reading title blocks were straightforward, this would not be an interesting problem. It is not straightforward. Six routine realities in Australian mining drawing libraries break naive OCR at scale, even modern and well-tuned OCR.
- Template variation
- A single asset's drawing library typically contains 30 to 100 distinct title-block templates, accumulated over decades of contractors, vendors, and CAD migrations such as Bentley, AutoCAD, and hand-stamped legacy prints. The fields are in different positions, with different labels, on every template family.
- Multi-line titles
- AS 1100 permits a title to wrap across multiple lines. Most templates use a hierarchical structure of system, scope, and sheet. OCR sees four strings. Without knowing the hierarchy, the four-line title becomes searchable as a single 150-character mash.
- Crossed-out revisions
- When a drawing moves from one revision to the next, older revision letters are often struck through. The current revision might be "D" but an OCR pass returns "ABCD". A pipeline that does not understand strikethroughs will index every drawing in your archive at the wrong revision.
- Status stamps
- "AS BUILT", "FOR CONSTRUCTION", "DRAFT", "ISSUED FOR REVIEW". These are often applied as stamps over an existing title block, partially obscuring the fields beneath. They are also the single most important indicator of whether a drawing should be trusted for operational decisions.
- Sheet relationships
- "Sheet 1 of 11" is straightforward. "Sheet 1 to 11" (a single sheet describing the relationship between an 11-sheet set) is a different statement entirely. Many legacy templates use the two interchangeably.
- Rotation and scan quality
- Mining site copiers from the 2010s scanned A1 prints rotated, skewed, and partially cropped. A typical legacy library has 5 to 15% of drawings rotated by 90 or 180 degrees, and another 10% with embedded bitmap regions that destroy text recognition.
Each of these problems is solvable individually. Most products handle two or three. The compounding effect, a rotated 2008 scan with a four-line title, three crossed-out revisions, an "AS BUILT" stamp over the revision block, and three competing ID systems, is what reliably breaks pipelines built for cleaner inputs.

