HL7 INU_U05 (Automated Equipment Inventory Update) | Integration Soup HL7 Reference Guide

HL7 INU_U05 Automated Equipment Inventory Update

Inventory telemetry for reagents, tips, waste, and other analyzer consumables.

HL7 message structure INU_U05 groups and segments from HL7 v2.5.1 Hide structure

These are the generated groups and segments for the version selected at the top of the page. The article explains the workflow, and this panel follows the chosen HL7 version.

Message Structure

Segment	Name	Required	Repeatable
MSH	Message Header	Yes	No
SFT	Software Segment	No	Yes
EQU	Equipment Detail	Yes	No
INV	Inventory Detail	Yes	Yes
ROL	Role	No	No

INU_U05 sends inventory-item information from automated equipment to another application, usually a Laboratory Automation System or middleware component. It is the message for reporting that a reagent, diluent, tip rack, waste container, wash solution, or other equipment-managed item has changed status or quantity.

The receiver uses it to warn operators, stop routing work that cannot be run, or reconcile what the instrument says it has available.

A small INU U05 example

MSH|^~\&|ANALYZER01|CORELAB|LAS|CITYHOSP|20260723102500||INU^U05^INU_U05|INU050001|P|2.5.1 EQU|ANALYZER01^Chemistry Analyzer 1^CITYHOSP|20260723102500|BUSY^Busy^HL70365|REMOTE^Remote control^L|W^Warning^HL70367 INV|GLUCREAGENT^Glucose reagent^L|LOW^Low^HL70383|REAGENT^Reagent^L|BAY3^Reagent bay 3^L|||100|18|15|82|mL^milliliter^UCUM|20260831000000|LOT7781^CITYHOSP

What workflow it represents

The equipment owns a local view of the inventory installed on or near it. INU_U05 publishes that view so the receiving system can decide whether the equipment can continue running the work assigned to it.

This can be a change notification, a periodic inventory report, or the answer to an INR_U06 inventory request.

How to read the structure

MSH carries the update event. Optional SFT can identify the sending software. Required EQU identifies the equipment whose inventory is being reported.

Repeating required INV rows carry the inventory details: substance identifier, status, substance type, container or carrier position, quantities, units, expiration, lot, and related inventory attributes. Optional ROL can identify responsibility when a profile uses it.

Implementation traps

Inventory status and inventory quantity are not interchangeable. A reagent can have measurable volume and still be unavailable because it is expired, not calibrated, blocked, or reserved.

Units matter. If the sender reports counts for tips, milliliters for reagent, and percent for waste, the receiver should not store them as naked numbers.

Also decide whether INU_U05 is authoritative or advisory. Some sites use it for operator alerts only; others let it affect routing and scheduling. Those are very different risk levels.

Reference notes

HL7 v2+ describes INU_U05 as a message for sending inventory-item information from one application to another, such as automated equipment to a Laboratory Automation System.