Equipment Identification and Numbering in GxP Facilities

Compliance within cGMP (and really, any commercial) facilities can be affected by the choice of equipment and instrumentation numbering strategies.  Numbering strategies can affect the convenience of implementation, traceability of documentation, implementation of tracking software, and can affect interdepartmental activities.

To clarify, by “numbering strategy”, I am referring to the manner in which numbers, (or other identifiers which may include text/numeric values), are assigned to equipment and instrumentation.  Often, these are assigned to assist in traceability for accounting, calibration, validation, maintenance, and use as a general reference in drawings, standard operating procedures, batch records, etc.  Of course, there are other numbering requirements as well, but these are some of the primary uses in cGMP facilities.

It is tempting to design a single numbering system that addresses all of these needs.  This would have obvious apparent benefits of simplicity and uniformity, and thereby, improved compliance.  For example, your tracking software and hard-copy files could all be organized by a single number scheme.  In practice, the author has never seen a case where this approach has resulted in any of these benefits, and usually instead results in gaps and inconsistencies.  The issues stem from the fact that the requirements for numbering are diverse. It is difficult, if not impossible, to design an efficient system that meets all requirements.  The following table summarizes some of the variety of requirements for each system:


Numbering System (Example)PurposeEquipment AffectedTimingPrimary Department AffectedNumbering RequirementsInformation Required to Assign IDID Lifespan
Asset ID


Accounting (depreciation)Equipment over a certain valueAssigned upon receiptAccounting Dept 


Value of equipmentID is tied to the specific item.  A replacement item is assigned a new ID.
Calibration ID

(CID 00012)

Calibration TrackingCalibrated Equipment and/or subcomponents of equipmentAssigned prior to routine calibrationCalibration Dept 


Owner,usage, and whether it is calibratableID is tied to the specific item.  A replacement item is assigned a new ID.
Maintenance ID

(M 112345)

Maintenance TrackingEquipment and/or subcomponents of equipment that require maintenanceAssigned prior to routine maintenanceMaintenance Dept 


Owner, usage, and whether it requires maintenanceID is tied to the specific item.  A replacement item is assigned a new ID.
Validation ID

(VID 99222)

Validation TrackingEquipment used for cGxP applicationsAssigned prior to validationValidation Dept 


Owner, usage, and whether it requires validationID is tied to the specific item.  A replacement item is assigned a new ID.
General Equipment ID


Identify equipment for general referenceAny equipment or componentAssigned prior to general useAll DeptsDescribes Function, UniquenessType of equipment/system and functionalityID remains the same if item is replaced, so that documentation remains relevant.


Review of the above table clarifies that the requirements for each type of ID are different and affect different pieces of equipment.  In addition, different specialties are required to determine if a number is even required for some equipment.  A few examples are presented below to identify some of the potential issues:

  • It is difficult to use Asset IDs for general equipment because they are generally only assigned to equipment over a certain value, so, for example, they wouldn’t be useful for tracking pipette or gauge calibrations, or any items below the prescribed value.  In addition, they are often not descriptive of the function of equipment.
  • General Equipment IDs can be used for calibration, maintenance, and validation, but a system needs to be set up to account for the granularity of components of each system.  For example, a sterilizer may have multiple components that are calibrated, so the system needs to account for the fact that part of the system may be calibrated with one procedure, and part by another.
  • General Equipment IDs may also need to overcome the problem that the calibration system, for example, is tied to the specific equipment item, so if an item is replaced, a manner of documenting its replacement in the calibration files is required.
  • If different IDs are used for each type of numbering, they should be readily distinguishable to prevent human and/or electronic (barcode scanners) from potentially recording an incorrect number.

All of that said, it is possible to combine some numbering systems depending on how equipment is managed, and some of the above assumptions can be modified depending on the manner in which the document filing systems are set up and managed.  However, Asset IDs are almost never a good substitute for any of the others because Asset IDs only cover high cost equipment; and General Equipment IDs are usually not a good substitute for Calibration IDs because if the equipment is replaced, the General Equipment ID usually stays the same and the Calibration ID is replaced to reflect a new calibration history.

Also, keep in mind that in any database the numbers are likely to be listed in an order determined by that database.  More on this in a future post.  Happy numbering!