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Influence of O2 contents on human beings
| O2 content/% | Influence on occupant |
|---|---|
| 21 | Normal |
| 17 | Long-term safety limit |
| 15 | Feeling of fatigue |
| 10 | Dizzy with short of breath |
| 7 | Unconsciousness, memory judgment malfunction |
| 5 | The lowest limit to maintain life |
| 2–3 | People die within several minutes |
