Preparation: Readiness Evidence
Domain 1: Preparation
Preparation tests whether you can make a bioprocess area, equipment set, and documentation package ready before execution. In the Craftsman Bio Process exam, readiness is treated as evidence, not intent: every claim must be backed by a record, a label, or a measured value.
Core rules
- Line clearance precedes staging. Remove previous batch materials, reconcile labels, and record the clearance before bringing in new components.
- Respect clean and dirty hold times. A vessel past its clean hold limit is not “visually clean”; it needs re-cleaning and re-release. Dirty hold limits control how long soiled equipment may wait before cleaning.
- Verify calibration and qualification status for critical instruments such as pH, conductivity, temperature, pressure, and flow sensors before use. An out-of-calibration sensor invalidates the data it touches.
- Single-use assemblies: inspect for damage, confirm part number and lot, perform the leak test, and record the assembly ID on the batch record.
- Media and buffer preparation: calculate against the batch record formula, verify water quality (for example WFI or purified water), measure pH and conductivity after mixing, and perform filter integrity testing where sterile filtration is required.
- Autoclave loads: use a validated load pattern, include biological and chemical indicators, and do not exceed load density or mix incompatible items.
Worked example
A 200 L bioreactor is scheduled for a 72 h run. Its clean hold limit is 24 h, but it was cleaned 30 h ago. The operator sees no residue and wants to proceed. Correct decision: do not proceed. The vessel has exceeded its clean hold; re-clean, re-rinse, and re-release before SIP. Reasoning: clean hold is a validated time limit, not a visual judgment. Proceeding would make the contamination-control claim unsupported.
Traps that cost marks
- Treating “looks clean” as release.
- Forgetting that filter integrity must be tested pre-use and post-use.
- Missing a calibration expiry by one day.
- Staging materials before line clearance is documented.
- Recording a preparation step after the fact instead of concurrently.