Cultivation · Controlled Procedure
VC-SOP-0142 — Germination Bay Sterile Technique
The controlled aseptic procedure for the germination bays: gowning by zone, surface and airflow cleanliness, and contamination control for seed lots and tissue culture, so that a single contaminated propagule never seeds a bay-wide loss.
The germination bays run unidirectional clean-to-dirty; no exceptions. Personnel, materials, and airflow move from the highest cleanliness class outward, never back. A breach of aseptic technique — a missed gowning step, a back-flow, an unsanitized transfer — contaminates not one seed but the entire tissue-culture cohort sharing that air. Any suspected breach holds the bay, quarantines the affected lots, and is reported to the Cultivation Lead immediately.
1. Purpose
To define the controlled aseptic procedure for working in the germination bays, where seed lots and tissue-culture explants are at their most vulnerable to fungal, bacterial, and viral contamination. The objective is to hold each cleanliness zone within its class limit through disciplined gowning, surface and airflow control, and one-way material flow, protecting both the founding genetics and any toxin-pathway cultivars propagated here.
2. Scope
Applies to all germination bay zones — the gowning anteroom (Z-0), the general germination floor (Z-1), the tissue-culture suite (Z-2), and the laminar-flow transfer hoods (Z-3) — and to all personnel, seed lots, and culture vessels within them. Downstream cultivation of cleared propagules is governed by VC-SOP-0101; incoming seed lots arrive screened per VC-SOP-0205. Bay climate and airflow setpoints are maintained under VC-SOP-0212. Excludes greenhouse grow-out and field operations.
3. Definitions
| Term | Definition |
|---|---|
| Cleanliness Class | The maximum airborne particle / viable-count limit permitted in a zone; lower number = cleaner. |
| Aseptic Technique | The set of practices that prevent introduction of contaminants to an exposed culture or seed. |
| Laminar-Flow Hood | A workstation supplying HEPA-filtered unidirectional air over the work surface (zone Z-3). |
| Gowning | The zone-specific protective garb donned in sequence before entering a cleaner zone. |
| Clean-to-Dirty Flow | The mandatory one-way movement of people and materials from cleaner to less-clean zones. |
| Excursion | A particle or viable count exceeding the zone class limit; triggers a hold. |
4. Responsibilities
| Role | Responsibility |
|---|---|
| Cultivation Lead (Owner) | Authorizes bay entry; holds the bay on a suspected breach; owns this SOP and its review. |
| Germination Technician | Performs gowning and aseptic transfers; runs settle plates; logs environmental monitoring. |
| Tissue Culture Specialist | Performs explant work in Z-3 hoods; inspects cultures for contamination. |
| Facilities Engineer | Maintains HEPA filtration and zone pressure cascade per VC-SOP-0212. |
| CHLORA | Monitors zone particle counts and pressure cascade; logs gowning-room access; raises an excursion alarm and holds the affected zone. |
5. Equipment & Pre-Checks
- Pressure cascade verified: Z-3 hood > Z-2 > Z-1 > Z-0 (each step ≥ 10 Pa positive inward)
- HEPA filtration in date; laminar-flow hoods passed their airflow-velocity check (0.45 m/s ±20%)
- Sterile gowning stock by class staged in the anteroom; nothing past its sterility date
- Surface sanitizer (70% denatured alcohol) and sporicidal agent in date
- Settle plates / active air sampler ready for the day's environmental monitoring
- Seed lots and culture vessels labelled, screened (VC-SOP-0205), and staged in pass-through
6. Cleanliness Class & Gowning by Zone
Each zone carries a cleanliness class limit and a gowning requirement. Gowning is cumulative: entering a cleaner zone requires everything from the outer zones plus the zone's own additions.
| Zone | Cleanliness Class | Gowning Requirement | Permitted Work |
|---|---|---|---|
| Z-0 Anteroom | Class D (≤ 3.5M part/m³) | Shoe covers, hairnet, gown over street clothes, hand sanitize | Gowning, hand hygiene, staging only. |
| Z-1 Germination Floor | Class C (≤ 352k part/m³) | Add coverall, mask, single gloves | Seed sowing, tray handling, settle-plate runs. |
| Z-2 Culture Suite | Class B (≤ 3.5k part/m³) | Add sterile hood gown, goggles, double gloves | Media pouring, culture inspection, vessel transfer. |
| Z-3 Laminar Hood | Class A (≤ 3.5k @ 5µm = 0) | Add sterile over-sleeves; gloves sanitized at hood | Explant cutting, subculture, aseptic transfer. |
Double-gloving from Z-2 inward. The outer glove is sanitized on entry to the hood and changed on any contact with a non-sterile surface; the inner glove is the last barrier and is never exposed. Gowning is removed in strict reverse order in the anteroom — gross-to-clean — on exit.
7. Procedure
7.1 Pre-Entry & Pressure Verification
- Confirm the pressure cascade and HEPA status on the CHLORA panel before any entry; a failed cascade holds the bay.
- Review the day's environmental monitoring trend; a recent excursion blocks Z-2/Z-3 work until cleared.
- Verify seed lots / vessels are screened and staged in the pass-through, never carried in from outside.
7.2 Gowning Sequence
- In Z-0, gown in the Section 6 order for the deepest zone to be entered; never skip a step to save time.
- Hand-sanitize at each zone boundary; don the additive garb for the next class before crossing.
- Inspect gloves and gown for integrity at the boundary; replace any compromised item before proceeding.
7.3 Surface & Airflow Control
- Sanitize the hood work surface with 70% alcohol and allow full contact time before placing any sterile item.
- Work at least 15 cm inside the hood face; keep no object upstream of an exposed culture in the laminar flow.
- Minimize arm movement and never break the air curtain by withdrawing and re-entering rapidly.
7.4 Aseptic Transfer & Seed Handling
- Flame or use single-use sterile tools; one tool per vessel where cross-lot transfer is possible.
- Open culture vessels only within the hood; keep open time and exposed area minimal.
- Move material clean-to-dirty only; a vessel that has left a cleaner zone never returns to it.
7.5 Environmental Monitoring & Excursion Response
- Run settle plates / active air sampling per the monitoring plan; incubate and read against the zone class limit.
- On an excursion, CHLORA holds the affected zone; the Cultivation Lead quarantines exposed lots and investigates.
- Resume only after the source is corrected and two consecutive clean monitoring results are recorded.
7.6 Quality Checkpoints
- Pressure cascade and HEPA verified before entry
- Gowning performed in full sequence for the deepest zone entered
- Hood sanitized with full contact time before sterile work
- Clean-to-dirty flow maintained; no back-flow of people or material
- Environmental monitoring within zone class limits; excursions held and cleared
8. Records
- Gowning-room access and gowning log per session (CHLORA, retained 3 years)
- Environmental monitoring results (settle plates / air sampler) by zone
- Pressure cascade and HEPA verification records
- Excursion investigations and quarantine actions
- Seed-lot and culture-cohort traceability to VC-SOP-0101
9. References
- VC-SOP-0101 — Specimen Cultivation Cycle Management
- VC-SOP-0205 — Specimen Intake & Quarantine
- VC-SOP-0212 — Greenhouse Climate Control
VC-SOP-0143— Media Preparation & Sterilization- Monitoring Systems · Operational Metrics
10. Revision History
| Rev | Date | Author | Summary |
|---|---|---|---|
| A | 2087-10-02 | Cultivation Lead | Initial issue; four-zone cleanliness model and gowning sequence established. |
| B | 2089-08-11 | Cultivation Lead | Double-gloving from Z-2, excursion hold rule, and clean-to-dirty flow formalized. CBO approval. |
| Review overdue: Next Review 2091-08-11 has elapsed; Rev C revalidation is open with the Cultivation Lead pending CBO scheduling. Document remains in force until superseded. | |||