Cleanroom testing and certification to ISO 14644
Key facts
Main standards
Occupancy states we test
Who needs it
Deliverables
Tests
| Group | Test | Purpose |
|---|---|---|
| Core (classification) | Airborne particle count | Determines the room ISO Class to ISO 14644-1 |
| Core | Airflow velocity / volume | Confirms clean air supply and air change rate |
| Core | Room pressurisation | Controls the direction of flow from cleaner to less clean areas |
| Core | Installed filter leak test (HEPA) | Confirms the filters and frames do not leak |
| Additional | Airflow visualisation (smoke pattern) | Shows the direction of airflow, confirming there is no backflow from lower-grade to higher-grade areas and that air does not move from less clean zones, or across operators or equipment, in a way that could carry contamination into higher-grade areas |
| Additional | Recovery test | Measures how long the room takes to return to its clean state after a contamination event |
| Additional | Temperature, humidity, lighting, noise | Checks the environment against the design |
| Equipment | Biological safety cabinets (BSC), laminar airflow units (LAF), AHUs | Confirms the equipment operates within specified values |
Photos from real sites
Examples of tests carried out by the QV TEST team in clients’ cleanrooms






How we work
Frequently asked questions
How often must a cleanroom be retested?
ISO 14644-2:2015 sets a maximum interval of 12 months for particle counting, airflow volume or velocity, and pressure differential. PIC/S GMP Annex 1 (PE 009-17) requires requalification of Grade A and B areas every 6 months and Grade C and D areas every 12 months.
How do ISO Class and GMP Grade differ?
ISO Class (1–9) is the cleanliness level based on particle concentration in ISO 14644-1. GMP Grade (A–D) is the level used for sterile medicinal product manufacture under PIC/S GMP Annex 1, which sets both particle and microbial limits in the at-rest and operational states.
How many particle sampling locations are needed?
It depends on the room area, per ISO 14644-1:2015 Table A.1. For example, a 10 m² room needs 5 locations, a 52 m² room 10 locations and a 1,000 m² room 27 locations.
What do I receive after testing?
A report covering every test with the sampling location plan, acceptance criteria, conclusions and copies of instrument calibration certificates.

