Breathing air is a precondition for human life, more accurately, the oxygen of the air which is essential for the combustion processes of the human body. The air required by an adult human depends on various influences and can be indicated by way of example only. The average bio-physical data of the human in a state of rest form a basis with the following values:
Table 1.11.1 - Human Bio-Physical Data| Weight | 60 kg |
| Energy Consumption | 70 kcal/h |
| Number of Breaths | 16 min |
| Quantity of Breathing Air | 0,5 m3/h |
The air requirement of the human being at different activities, deduced from the above, is summarised in the following table.
Table 1.11.2 - Human Requirement of Air| Activity | Energy Consumption | Air Requirement m3/h |
|---|
| At Rest | 70 | 0,4 - 0,5 |
| Office Work | 100 | 2 - 5 |
| Light Work | 150 | 10 - 15 |
| Manual Work | 350 | 10 - 36 |
| Heavy Work | 500 | 40 - 60 |
| Very Heavy Work | 600 | 72 - 90 |
The air inhaled by an adult human in the absence of bodily activity contains about 0.5 m3/h where the air exhaled, on average, contains 17% O2; 4% CO2 and 79% N.
