Airflow Direction Test: New Acceptance Criterion
The airflow direction test – typically performed as a smoke test – is a key element of every cleanroom qualification and Contamination Control Strategy. It visualizes in which direction air flows between two areas and thus demonstrates that pressure cascades, airlock concepts and barriers work exactly as designed. The goal is to reliably carry potential contamination away from critical product and working zones – a core requirement of GMP Annex 1 and relevant cleanroom standards.
The Previous Acceptance Criteria
Up to now, Moqlero allowed testers to evaluate an airflow direction measurement against two assessing criteria plus one purely informative option:
- Overflow present / no flow: accepts a correctly directed airflow as well as a standing air column, as long as there is no back-flow into the critical area.
- Counter-flow: intentionally allows setups in which a flow opposite to the tested direction is permitted or even desired.
- n.d. (not defined): a purely informative criterion without a pass/fail evaluation, e.g. for orientation measurements or development studies.
- New – Overflow Only: the new, strictest acceptance criterion.
What the New "Overflow Only" Criterion Delivers
With "Overflow Only", only a clearly directed airflow in the tested direction is rated as passing. A standing air column or a counter-flow results in a fail – even if no active back-flow into the critical area is observed. This allows Moqlero to cleanly cover protection concepts that depend on a continuous, directional air movement – typically at highly critical transitions such as RABS/isolators, aseptic filling lines, or airlocks between Grade A and Grade B zones.
Why the Extension Is a Real Benefit
The fourth acceptance criterion lets you map the actual protection level of a measuring point even more precisely – without compromises and without manual re-evaluation. Quality assurance, validation, and production can choose exactly the criterion that fits each containment concept per measurement point: informative, tolerant, inverted, or strict. The result: stricter, GMP Annex 1-compliant assessments where they are needed – and pragmatic assessments where they are sufficient. All variants feed directly into the signed smoke test report and remain fully audit-ready at any time.
With "Overflow Only", the digital airflow direction documentation in Moqlero becomes even more flexible and at the same time more precise – perfectly aligned with the growing requirements of GMP Annex 1.