Natural and Civilizatory Factors

and water in our environment form (he basis of life for man, animals, and plants. Due to the natural capability of these important environmental media to regenerate, their composition may fluctuate between certain limiting values without endangering life in any way. These limits, in most areas, have not been reached yet and it is man s duty to see to it that this will never happen. 

As a side effect caused by man s activities in the manufacture and use of products, the natural composition of the media air, water, and soil is being affected. 

In contrast to the above, considerably higher concentrations of these substances are found—yearly average and for short periods—in polluted industrial and urban areas (Table 7.2). 

Alien substances in air, as far as they are found in large quantities in locally limited areas, are usually the consequence of human activities. In densely populated areas, a constant rise in nitrogen dioxide emissions over 

Substances (in g/m ) Yearly average for a short time, temporarily  

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Environment" is understood to comprise all life and matter, man, animals, and plants, air, water, and soil surrounding the technical object in question within the predetermined observation space. Depending on prevailing conditions, the environment can be limited around a vantage point, either nearer or farther. Of decisive importance here is how far the actions effect the operation of the machine in question or, conversely, are caused by it. Below we will first deal with the natural and civilizatory environmental factors affecting the machine from outside. Thereupon we shall look at the influence of the machine on the environment. In Section 7.3 we will examine—in a reverse direction, so to speak—the effect of machines within the environment on technical systems in question. 

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