The Standard

Labeling & encoding

How to put a UTID on a rapid test so any iaX reader — and any person — can identify the kit. This page defines the full-length UTID string, the two supported 2D symbologies, the sizes that read reliably, and where the label goes on the kit.

Anatomy of a full UTID string

A UTID sticker encodes a single, all-digit string: an optional U sentinel, then the mandatory 7-digit identity (this is what the public catalog lists and what a reader matches to a detection profile), then an optional, manufacturer-defined numeric suffix for the manufacturer’s own traceability — a manufacturing date and serial (V-MMM-TTT-YYMMDD-XXXX), or any numeric scheme they choose. The reader uses only the first seven digits to identify the kit and records the rest verbatim — it does not interpret the suffix.

Everything in the symbol is digits (plus the optional leading U). No letters, no +, no URLs — a reader ignores anything that isn’t this shape.

The production suffix (manufacturer-defined)

After the 7-digit identity, a manufacturer may append a numeric suffix for its own traceability — a manufacturing date and serial, or any numeric scheme it chooses. The layout is up to the manufacturer; the iaX reader records the digits with the result but does not interpret them, and selects the profile on the first seven digits only. The recommended form is V-MMM-TTT-YYMMDD-XXXX — a YYMMDD date and a serial — shown below; it is a recommendation, not a required format:

Field	Position	Digits	Format	Example
Identity	1–7	7	V MMM TTT	1014071
Manufacturing date	8–13	6	YYMMDD	260615
Serial (XXXX)	14–17	4	0000–9999	0042

Identity only (sentinelled)

U1014071

1-014-071

Identity + date

U1014071260615

1-014-071 · MFG 2026-06-15

Full string

U10140712606150042

1-014-071 · MFG 2026-06-15 · SN 0042

Reader-enforced facts

The whole payload is numeric (optionally a single leading U), 7–34 digits, and the first 7 digits are the identity. A nativealphanumeric lot or serial code must stay in the manufacturer’s own barcode — the UTID payload is digits only, so a UTID with letters will not be recognised.

iaX readers select the detection profile from the 7-digit identity and record the full digit string verbatim with every result. They do not interpret anything after the first seven digits — the suffix is the manufacturer’s own traceability data, carried through to the record as-is.

How an iaX reader validates a UTID

A cassette usually carries several symbols — the manufacturer’s own DataMatrix or QR, a GS1 element string, sometimes an IFU URL — and the UTID sticker sits alongside them. So the reader does not “scrape” digits from whatever it sees; it accepts a symbol as a UTID only when the whole payload matches the UTID shape. These are reader-enforced rules, not style guidance:

Whole payload is U + digits (new stickers) or digits only (legacy) — 7 to 34 digits.

The first 7 digits are the identity; the cloud re-derives the same key from them.

A leading U sentinel marks the sticker as provably a UTID, telling it apart from a manufacturer's own numeric code.

If two symbols name two different kits, the reader asks the operator — it never guesses.

Any letters, +, spaces, URLs or GS1 element strings → not a UTID; ignored for selection.

A bare number that happens to be 20 digits (e.g. a GS1 SSCC) is never allowed to override an operator's pick.

New stickers should carry the U sentinel: it costs one byte and makes the sticker unambiguously a UTID rather than a look-alike number. Bare-numeric stickers already in the field keep working.

Supported symbologies

iaX readers decode two 2D matrix symbologies, and the full digit string above fits comfortably in either. Linear (1D) barcodes are not used for the on-kit UTID — they are too wide and too low-density for a cassette.

DataMatrix (ECC 200)

Preferred

Rectangular format preferred (e.g. 8×32) — fits the narrow label strip on a cassette.
Highest data density in the smallest area.
ECC-200 error correction survives print wear.
The iaX decode pipeline is tuned for it.

QR Code (Model 2)

Supported

Decoded by the same iaX pipeline.
Use when the label area is larger.
Good for a human phone-scan.
Carries the identical U + digit payload.

Sizes & print quality

These are the reading-reliability minimums. When in doubt, print bigger, darker and matte.

Parameter	DataMatrix (preferred, iaX-read)	QR (optional)
Format / shape	Rectangular preferred — 8×32 modules for a full ~20-digit UTID (identity-only fits 8×18); square (e.g. 16×16) also decodes	Square (Model 2)
Module (cell) size	≥ 0.38 mm (0.40–0.50 mm recommended)	≥ 0.33 mm
Printed symbol size	≈ 4 × 16 mm rectangular for the full string (identity-only ≈ 4 × 8 mm)	≥ 15 × 15 mm
Quiet zone (clear border)	≥ 1 module (2 recommended), all 4 sides	4 modules, all 4 sides
Print resolution	≥ 600 dpi	≥ 600 dpi
Contrast	Dark modules on light background, ≥ 70% print contrast	Same
Finish	Matte / non-glossy (avoids glare under the iaX LED)	Matte / non-glossy

Placement on the kit

Put the symbol where the iaX camera can see it when the kit is seated, and where it never competes with the chemistry. The kits below — imaged by an iaX reader — show it in practice: two real cassettes already carrying a UTID DataMatrix, and one with the recommended placement illustrated.

Veterinary CDV Ag cassette carrying a UTID DataMatrix on the label, left of the C/T window — **Real kit — veterinary.** The UTID DataMatrix sits on the flat label, left of the C/T window and clear of the chemistry, with its human-readable code beside it.

Dengue serotyping cassette with two result windows carrying a single UTID DataMatrix — **Real kit — dual window.** One UTID identifies the whole kit; the DataMatrix sits on the label beside the result windows, not over them.

Cassette with the recommended UTID label placement illustrated on the blank label area — **Recommended placement (illustrated).** On the blank label area beside the window: a rectangular DataMatrix with the human-readable UTID beneath.

Flat top face, in the label / branding zone, within the reader's field of view when seated.

Upright orientation; the human-readable string (or a fiducial) marks 'up'.

≥ 2 mm clear margin from edges, fold lines and raised features.

One UTID identifies the kit; a multiplex panel carries one UTID in its main label zone.

Never over the result window, the membrane, or the sample well.

Not on curved surfaces, seams or fold lines.

No glossy laminate over the symbol (glare under the LED).

No color-on-color or low-contrast printing.

The label block, up close

A complete on-kit UTID label: the machine-readable symbol, the human-readable string for manual entry and verification, and the exact encoded payload.

1-014-071

MFG 2026-06-15

SN 0042

payload: U10140712606150042

The DataMatrix and QR symbols on this page are illustrative renderings, not scan-decodable codes.

Need a manufacturer or test-type code?

You need the 7-digit identity before you can print a label. Read the standard for how the code is structured, then request your code.

Request a UTID code →