Log: Column Cycle Life Tracking

This is a ready-to-use log for tracking chromatography column or membrane cycle life against a validated maximum. It exists to close the most common finding in this area: a validated limit that exists on paper with no reliable mechanism enforcing it. Replace every <<FILL: ...>> placeholder with your own specifics. A worked filled specimen follows.

Instructions

One log per physical column or membrane cassette, identified by its own serial number, not by resin lot.
Complete one row every time the column is used in a manufacturing cycle.
The validated maximum cycle count and the discard trigger are stated at the top and must match the current approved lifetime study.
A column reaching its validated maximum is discarded or repacked; a repacked column resets to cycle 0 only after packing qualification (HETP, asymmetry) is complete and documented.

Field	Entry
Column / membrane serial number	`<<FILL>>`
Resin / membrane type and lot	`<<FILL>>`
Step / process	`<<FILL>>`
Validated lifetime protocol/report reference	`<<FILL>>`
Validated maximum cycle count	`<<FILL>>`
Discard trigger	`<<FILL: e.g. "hard stop at cycle N, no exceptions without a new lifetime claim">>`
Last packing qualification date	`<<FILL>>`

Cycle log

Cycle #	Batch / lot processed	Date	Back-pressure (bar)	HETP / asymmetry (if tested)	Sanitization performed	Operator	Notes
1	`<<FILL>>`	`<<FILL>>`	`<<FILL>>`	`<<FILL>>`	Yes/No	`<<FILL>>`	`<<FILL>>`
2	`<<FILL>>`	`<<FILL>>`	`<<FILL>>`	`<<FILL>>`	Yes/No	`<<FILL>>`	`<<FILL>>`
`<<FILL: ...>>`

Approach to maximum: action required

Trigger	Action
10 cycles remaining to validated maximum	Manufacturing schedules a replacement column; Validation notified
Validated maximum reached	Column is discarded or removed from service; batch record system blocks further use of this serial number
Any attribute trending abnormally before the maximum	Raise a deviation; do not continue cycling pending assessment

Repack / requalification record (complete only if the column is repacked, not discarded)

Field	Entry
Repack date	`<<FILL>>`
New packing qualification result (HETP, asymmetry)	`<<FILL>>`
Qualification pass/fail	`<<FILL>>`
Cycle counter reset to 0, approved by	`<<FILL>>`

Sign-off

Role	Name	Signature	Date
Log maintained by (Manufacturing)	`<<FILL>>`
Periodic review by (Validation/QA)	`<<FILL>>`

Filled specimen

Illustrative Protein A column, validated maximum 150 cycles.

Field	Entry
Column serial number	PA-COL-0042
Resin type and lot	MabSelect PrismA, lot 3A7712
Validated maximum cycle count	150
Discard trigger	Hard stop at cycle 150; batch record system blocks cycle 151

Cycle #	Batch processed	Date	Back-pressure (bar)	Sanitization performed	Operator
148	BR-20260812-03	2026-08-12	2.2	Yes	J. Alvarez
149	BR-20260814-01	2026-08-14	2.3	Yes	J. Alvarez
150	BR-20260815-02	2026-08-15	2.3	Yes	M. Chen

At cycle 150 the column was removed from service the same day per the discard trigger; the batch record system was updated to reject serial number PA-COL-0042 for any further manufacturing use.

Common inspection findings this log prevents

A validated cycle limit that exists in the protocol but no record shows which physical column is on which cycle.
Tracking by resin lot instead of by individual column serial number, which loses the count when a lot is split across multiple columns.
A column used beyond its validated maximum because no system blocked it.
A repacked column silently continuing its old cycle count instead of requalifying and resetting.

How to adapt this log

Set the validated maximum from your current approved lifetime study; update this log immediately if the study is revised.
Decide whether this log is paper or built into your MES/batch record system; either way, the discard trigger must be enforced, not advisory.
Set your own approach-to-maximum trigger point (this template uses 10 cycles remaining as an example).
If repacking is permitted, require packing qualification before the counter resets.