In a risk-based inspection, WHO TRS 986 – Point 39.17 (as used in the risk-based inspection checklist) requires inspectors to verify the firm’s procedure for (1) selecting environmental monitoring (EM) sampling locations and (2) interpreting EM results for the sterile area, supported by the relevant SOPs and records, and to confirm whether the approach aligns with ISO 14644-1. CDSCO
What “risk-based” means here
WHO TRS 986 emphasizes Quality Risk Management: decisions and documentation effort should be commensurate with risk and grounded in scientific knowledge and process experience. gmp-compliance.org Applied to EM, this means sampling points and interpretation rules must be justified based on where contamination is most likely and most harmful.
What inspectors typically check under 39.17
1) Sampling location selection (documented rationale)
- A mapping of EM locations for each grade/room and critical zone (Grade A/B/C/D), focused on: product exposure points, aseptic connections, filling zones, air returns, operator proximity, and worst-case airflow patterns. World Health Organization
- Evidence that locations were chosen using a formal risk analysis and informed by room/zone qualification (classification) results. World Health Organization
2) ISO 14644-1 alignment (particle classification link)
- For non-viable monitoring/classification, ISO 14644-1 is the reference for classification of air cleanliness by particle concentration at designated sampling locations. ISO
- The firm should show how ISO classification/testing supports their EM plan (e.g., “critical locations,” occupancy state, sampling approach).
3) Interpretation of results (alert/action + trending)
- Defined alert and action limits, investigation triggers, and CAPA expectations (including trends, not only excursions). World Health Organization
- Proof that EM results are reviewed and considered for batch release decisions where relevant. World Health Organization
- Assurance that sampling during operations does not compromise zone protection. World Health Organization
In short, 39.17 expects a science- and risk-justified EM design with documented evidence that sampling locations and result interpretation are robust, compliant, and linked to cleanroom classification principles.