4. Classification of natural resources

The concept «environment» includes all natural elements, and also part of nature changed by people activity (settlements, agricultural areas, reservoirs and others). By natural resources we understand objects, conditions and processes, which are used or can be used in manufacturing for sufficing material, scientific and cultural needs of society.

The natural resources are divided into exhaustible and inexhaustible.

Inexhaustible natural resources include space (solar radiation and energy of marine flows and waves) and climatic (wind power and Earth bowels) power resources. Taking into account huge masses of air and water medium of the planet atmospheric air and water resources can be referred to inexhaustible resources too. But such reference is conditional, cause chemical structure and physical condition of atmosphere and hydrosphere get changed under people activity influence (anthropogenous influence) what can bring to losses of their biological value and possibilities of using. That makes necessary to execute a complex of works on supporting air and water purity.

Exhaustible resources in turn include renewable and nonrenewable natural resources. The renewable resources can be recreated during their using. The renewing goes at various velocity: formation of 1 cm of humus ground layer takes about 600   years, growing of cut down wood - dozens of years, animals’ population - up to 10 years. Thus, the rate of renewed resources using should be in balance with rate of their restoring. Nonrenewable natural resources are those which can’t be renewed absolutely or their renewing goes slower than their using. Minerals which using entails overcrop refer to such resources. Their protection should consist in economic, rational and complex using so resources will have a minimum loss. Besides, nonrenewable resource is the space people live in.

5. Ecological standardization

The main goal of ecological standardization is to identify all potential contaminants of environment and find exposure standards for them.

Exposure standards provide us with limits of acceptable concentrations.

THRESHOLD LIMIT VALUE (TLV) refers to maximal concentrations of substances to which it is believed that nearly all people may be repeatedly exposed day after day without adverse effect.

More detailed information about TLVs is introduced in further chapter on airborne contamination.

LIMITS OF ACCEPTABLE EMISSION: limit concentration of contaminants in the air for some period that shouldn’t exceed TLV within control area.

CONTROL AREA: territory surrounding enterprise that prevents harmful emissions from contaminating environment or at least reduces them.

Control areas are divided into 5 classes:

1 – 1000 m (chemical and refinery plants);

2 – 500 m (production of concrete, lime carbonate);

3 – 300 m (thermal power station, ferroconcrete plants);

4 – 100 m (electronic and machine building plants);

5 – 50 m (light and food industry plants).

Compliance of air quality with standards is checked by assessing concentration of harmful substances against their exposure standards.

Acceptable condition is C ≤ Cst.

In case of presence of several contaminants which action is reinforced by each other acceptable condition will be:

(1)