Air Composition
The air we breathe (and compress) is not a simple gas - it's a mixture.
"Pure" Air
| Component | Percentage |
|---|---|
| Nitrogen (N₂) | 78.08% |
| Oxygen (O₂) | 20.95% |
| Argon (Ar) | 0.93% |
| Carbon dioxide (CO₂) | 0.04% |
| Other gases | Traces |
In Reality
But this is only "pure" laboratory air. In reality, atmospheric air also contains:
| Component | Description |
|---|---|
| Water vapor | Humidity - varies by climate |
| Particles | Dust, pollen, soot |
| Microorganisms | Bacteria, spores, fungi |
| Pollutants | Hydrocarbons, SOx, NOx |
Why does it matter for compressed air?
When you compress air, you compress all of this together:
Atmospheric air with 1 mg/m³ of dust
↓
10:1 Compression
↓
Compressed air with 10 mg/m³ of dust
Contaminants concentrate by the same factor as compression.