Special technical conditions contain requirements regarding materials, fabrication and assembly of the structure, preparation of the welding plan, as well as the method and extent of special inspections of the steel structure. Welding plans and special controls form an integral part of the technical documentation.

When dimensioning steel structures, depending on their purpose, the following types of loads are taken into account: own weight and other permanent loads; moving load; snow; wind; impact of temperature changes; earth pressure; hydrostatic pressure; the effect of pressed rods on transverse supports; vehicle side impacts; various blows; the load that occurs during the installation of the structure; various occasional loads; braking force; centrifugal force; friction in bearings; moving supports; turning the supports, etc.

During test assembly, as well as during production, the dimensions of the steel structure and its parts are controlled, with the exception that the deviations must not exceed the values established by the regulations for tolerances of dimensions and shapes for supporting steel structures.