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Comprehensive reference for spacecraft manufacturing clean room requirements, ISO classifications, outgassing data, and contamination control procedures
Maximum allowable particle concentrations (particles per cubic meter) at specified particle sizes for each ISO class. Click any row to see space industry applications.
| ISO Class | Fed Std 209E | ≥0.1μm | ≥0.2μm | ≥0.3μm | ≥0.5μm | ≥1.0μm | ≥5.0μm |
|---|---|---|---|---|---|---|---|
ISO 1 | Class 1 | 10 | 2 | – | – | – | – |
ISO 2 | Class 10 | 100 | 24 | 10 | 4 | – | – |
ISO 3 | Class 100 | 1,000 | 237 | 102 | 35 | 8 | – |
ISO 4 | Class 1,000 | 10,000 | 2,370 | 1,020 | 352 | 83 | – |
ISO 5Common | Class 100 | 100,000 | 23,700 | 10,200 | 3,520 | 832 | 29 |
ISO 6 | Class 1,000 | 1,000,000 | 237,000 | 102,000 | 35,200 | 8,320 | 293 |
ISO 7Common | Class 10,000 | – | – | – | 352,000 | 83,200 | 2,930 |
ISO 8Common | Class 100,000 | – | – | – | 3,520,000 | 832,000 | 29,300 |
ISO 9 | Class 1,000,000 | – | – | – | 35,200,000 | 8,320,000 | 293,000 |
Max 3,520 particles per m\u00B3 at 0.5\u03BCm
Optics, detectors, focal plane assembly, solar cell fabrication
Max 352,000 particles per m\u00B3 at 0.5\u03BCm
General spacecraft assembly, bus integration, harness work
Max 3,520,000 particles per m\u00B3 at 0.5\u03BCm
Large structure assembly, solar arrays, antenna reflectors, CubeSats