Hygiene of urbanized territories

Impact of urbanization on the habitat

Modern urban planning is based on economic principles: the use of natural resources, the uniform distribution of productive forces and waterways. The leading process today has become urbanization — the expansion of cities and an increase in building density.

The process has both positive aspects (cultural development, convenience of management and organization of sanitary measures) and serious disadvantages from a hygienic perspective:

• overpopulation and crowding;
• traffic collapses;
• long distances between home and work;
• deterioration of environmental quality.

To minimize risks, planning must prioritize the impact of the environment on human health.

Selection of territory for construction

The site for a settlement must meet a number of environmental and sanitary criteria. The permissible loads on the natural environment and the availability of fuel and water resources are taken into account.

Hygienic requirements for the site:

• Dry, clean soil with a solid foundation.
• Absence of swamps nearby.
• Relief with gentle southern slopes for good insolation (steep slopes are dangerous for people with heart and lung diseases).
• Groundwater depth: at least 1.5 m for low-rise buildings and at least 2 m for high-rise buildings.
• Ideally, there should be water bodies and forests to improve the microclimate and water supply.

Functional zoning of the city

To protect the population from harmful factors, the territory is divided into three main categories:

1. Residential area. Intended for housing, public and administrative buildings, parks, and public gardens. It is permissible to place only those industrial facilities here that do not require sanitary-protection zones.
2. Industrial area. An isolated zone for factories, warehouses, transport hubs, and out-of-town communication routes.
3. Landscape and recreational area. Includes forests, forest parks, water bodies, and agricultural land, forming a unified system of open spaces for recreation.

Additionally, resort zones or historical development zones may be designated.

Sanitary-Protection Zones (SPZ)

A buffer — a sanitary-protection zone — must be established between the industrial and residential (or recreational) zones. Its size is regulated by SanPiN 2.2.1./2.1.1.1200-03 and depends on the hazard class of the enterprise:

For Class 1 and 2 enterprises, the size of the SPZ is approved by the Chief Sanitary Doctor of the Russian Federation based on a health risk assessment. For other classes, the decision is made by the chief sanitary doctor of the constituent entity of the Russian Federation.

Street layout systems

Proper street layout ensures ventilation and sufficient insolation of residential blocks.

• Grid (rectangular). Streets are straight and intersect at right angles. It is excellently ventilated and suitable for coastal cities (for example, on the Volga). The downside is complex transport logistics in large megacities.
• Radial. Main thoroughfares run from the center to the outskirts, intersected by ring streets (an example is Moscow). Convenient for transport, it allows houses to be built in a staggered order inside the rings for quiet and light.

Historical "cobweb" development with crooked narrow alleys is considered hygienically unfavorable because it hinders traffic movement and creates air stagnation.

Class and exam questions

What else to study on this topic

• Growth dynamics of megacities and cities with a population of over a million
• Classification of settlements by population size (from small to largest)
• Impact of high building density on the microclimate
• Modern reconstruction of historical cities using Moscow as an example

Other topics in the section "Chapter 4. Ecological and hygienic problems of populated areas and housing"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.