QA/QC Tools · ISO 14644-1 · EU GMP Annex 1
Cleanroom Classification Calculator
Determine ISO cleanroom class from particle count data and cross-reference EU GMP Grades A–D. Interactive particle-count input with Pass/Fail against target classes—editorial guides like GMP Insiders and ACE Engineering publish tables but do not offer a free classification calculator.
Quick Answer
Pharmaceutical cleanroom classification compares measured airborne particle concentrations to ISO 14644-1:2015 limits and EU GMP Annex 1 grade requirements. Enter ≥0.5 µm and ≥5 µm counts per m³ to determine ISO Class 1–9 and cross-reference EU Grades A–D. Annex 1 requires classification at rest and in operation for sterile manufacturing; Grade A critical zones must maintain ISO 5 in both states. This free calculator supports QA review—full qualification still requires ISO 14644-1 sampling location, volume, and statistical rules.
Unit conversion
particles/m³ = particles/ft³ × 35.31
ISO 14644-1 limits are per cubic meter. Legacy US Federal Standard 209E references often use per ft³. Primary classification parameter: ≥0.5 µm. Secondary (Annex 1): ≥5 µm.
Classify from particle counts
Enter your particle counter readings per m³ for the two standard monitoring channels.
ISO Class
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EU GMP Grade
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Fed. Std. 209E
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Lookup by ISO class or EU grade
Select a cleanroom class to view particle limits, equivalents, and typical pharmaceutical use.
ISO 14644-1 Classification Limits (particles per m³)
| ISO Class | ≥ 0.1 μm | ≥ 0.2 μm | ≥ 0.3 μm | ≥ 0.5 μm | ≥ 1 μm | ≥ 5 μm | EU Grade | US 209E |
|---|---|---|---|---|---|---|---|---|
| ISO 1 | 10 | 2 | — | — | — | — | — | — |
| ISO 2 | 100 | 24 | 10 | 4 | — | — | — | — |
| ISO 3 | 1,000 | 237 | 102 | 35 | 8 | — | — | Class 1 |
| ISO 4 | 10,000 | 2,370 | 1,020 | 352 | 83 | — | — | Class 10 |
| ISO 5 | 100,000 | 23,700 | 10,200 | 3,520 | 832 | 29 | Grade A/B | Class 100 |
| ISO 6 | 1,000,000 | 237,000 | 102,000 | 35,200 | 8,320 | 293 | — | Class 1,000 |
| ISO 7 | — | — | — | 352,000 | 83,200 | 2,930 | Grade C | Class 10,000 |
| ISO 8 | — | — | — | 3,520,000 | 832,000 | 29,300 | Grade D | Class 100,000 |
| ISO 9 | — | — | — | 35,200,000 | 8,320,000 | 293,000 | — | — |
EU GMP Grade Equivalents — At Rest vs In Operation (Annex 1)
| EU Grade | At Rest (ISO) | In Operation (ISO) | Typical Use |
|---|---|---|---|
| Grade A | ISO 5 | ISO 5 | Aseptic filling zone, LAF workstations, stopper bowl |
| Grade B | ISO 5 | ISO 7 | Background environment surrounding Grade A for aseptic preparation |
| Grade C | ISO 7 | ISO 8 | Less critical aseptic preparation and filling steps |
| Grade D | ISO 8 | Not defined | Non-aseptic areas; gowning rooms; handling of closed containers |
Annex 1 §4.27–4.29 requires total particle measurement for ≥0.5 µm and ≥5 µm at rest and in operation. Classification should be performed during simulated operations; reclassification may use simulated operations or APS.
How to Use This Calculator
Worked Example
Grade A zone — at rest classification
Measured: ≥0.5 µm = 2,800 particles/m³, ≥5 µm = 0 particles/m³
ISO 5 limit for ≥0.5 µm = 3,520. 2,800 < 3,520 ✓
ISO 5 limit for ≥5 µm = 29. 0 < 29 ✓
Result: ISO Class 5 / EU Grade A — within limits ✓
Pharma / GMP Context for QA Professionals
Cleanroom classification is part of cleanroom qualification under EU GMP Annex 1 and supports contamination control strategy (CCS) for sterile medicinal products. Classification establishes that airborne particle concentrations meet specified limits; ongoing environmental monitoring confirms conditions are maintained in relation to product quality. Initial classification is typically performed at rest and during simulated operations; periodic reclassification follows ISO 14644-2 intervals and site quality procedures.
At-rest and in-operation states carry different ISO expectations for Grades B–D. Grade A critical zones must maintain ISO 5 in both states—there is no relaxation during production. Grade B background may be ISO 5 at rest but ISO 7 in operation, reflecting personnel and equipment activity. When interpreting calculator results, confirm which occupancy state your particle counts represent before comparing to Annex 1 Table 1 limits.
Environmental classification connects to broader QA readiness. Process capability analysis via the Process Capability Cpk Calculator quantifies manufacturing variation during validation. FMEA risk prioritization with the RPN Calculator identifies high-risk process steps that may warrant tighter environmental controls. Pre-inspection preparation uses the GMP Checklist Generator and Audit Readiness Checklist alongside environmental qualification records.
Limitations and Qualification Caveats
- Single-point particle counts cannot replace full ISO 14644-1 classification with defined sampling locations, minimum sample volumes, and statistical evaluation.
- Results must be interpreted for the correct occupancy state—at rest vs in operation—and matched to the applicable Annex 1 grade requirement.
- Microbial monitoring, viable particle assessment, and pressure cascade verification are separate from non-viable particle classification.
- Major facility or process changes trigger reclassification regardless of the routine ISO 14644-2 schedule.
Evidence and Sources
- ISO 14644-1:2015 — Classification of air cleanliness by particle concentration
- ISO 14644-2 — Monitoring to provide evidence of cleanroom performance
- EU GMP EudraLex Volume 4 — Annex 1: Manufacture of Sterile Medicinal Products (2022)
- FDA Guidance: Sterile Drug Products Produced by Aseptic Processing (2004)
- Competitive landscape: GMP Insiders publishes ISO-to-EU-grade mapping tables and educational content for pharmaceutical cleanrooms but offers no interactive particle-count classification tool. ACE Engineering provides consulting-firm Grade A–D reference tables without a free calculator or QA hub cross-links. NovaPharmaNews combines ISO 14644-1 limit lookup with live particle-count input, Pass/Fail against target grades, and integration with Cpk, FMEA, and GMP audit tools.