A Shield Against the Snow: How Snow-Retaining Barriers are Designed and Certified in Russia and Worldwide

The Specifics of Avalanche Protection Unlike rockfalls, where a barrier catches an already falling object, snow-retaining barriers (also known as avalanche protection structures) operate on the principle of preventive protection. They are installed in transit zones and, most importantly, directly within the avalanche starting zone (release area).

A structure made of structural posts and high-tensile meshes (often utilizing the same reliable ring net weaves as in rockfall protection) is installed perpendicularly to the slope. Its task is to retain the multi-ton static mass of the snowpack, prevent snow gliding, and stop the avalanche from releasing downhill. Such systems experience tremendous static and quasi-static loads, which is why their design relies on a strict regulatory framework.

Swiss Guidelines: The Historical Benchmark Historically, Switzerland has been the trendsetter and undisputed authority in the field of snow research. The Institute for Snow and Avalanche Research (WSL/SLF), in collaboration with the Federal Office for the Environment (FOEN), developed a fundamental document: the "Guidelines for avalanche control in the starting zone" (Richtlinie für den Lawinenverbau im Anbruchgebiet).

It was the Swiss standards that first detailed the physics of the snowpack, introduced snow gliding coefficients for various soil types, and provided the world with mathematical formulas to calculate the snow pressure on the barrier's structural elements. These calculations still form the basis of most projects worldwide today.

European Standards: ONR 24805 and Flexible Systems With the advancement of technology, rigid steel and concrete structures were replaced by flexible systems based on wire ropes and high-tensile meshes. The main European document regulating these specific flexible snow-retaining net barriers is the Austrian standard ONR 24805 (Avalanche protection - Avalanche protection nets).

This standard defines strict requirements for materials (load-bearing capacity of steel wire ropes, connection components, anti-corrosion coatings) and outlines the methodology for the static testing of flexible structures. Compliance with the ONR 24805 standard is de facto a mark of the highest quality in the European market.

The Russian Regulatory Framework: SP, ODM, and TU In Russia, the approach to standardizing mountain snow-retaining systems has its own specific features. It is important for clients not to confuse mountain avalanche protection barriers with building roof snow guards (for which a separate standard, GOST R 59634-2021, exists).

The design and legalization of mountain avalanche barriers in the Russian Federation are based on the following documents:

SP 116.13330.2012 (Code of Practice: "Engineering protection of territories, buildings and structures from dangerous geological processes"): This is the primary regulatory document for the design engineer. The SP strictly mandates the collection of climatic data (maximum height and density of the snowpack, wind rose, slope steepness) and defines the principles of barrier layout (distance between rows, angle of structure inclination).

ODM 218.6.031–2018 (Sectoral Road Methodological Document of Rosavtodor): This document explicitly describes the use of ring nets as snow-retaining barriers in avalanche starting zones, emphasizing their effectiveness in protecting transport infrastructure.

Factory Technical Specifications (TU): Since there is no single "product-specific" national GOST for avalanche protection nets in the Russian Federation, the quality and durability of the structure (strength of wire ropes, reliability of ground anchors) are ensured by the strict Technical Specifications (TU) of the manufacturing enterprise. These, in turn, rely on basic GOSTs for metal products and hardware.

Conclusion Designing snow retention systems is a complex geophysical task. A reliable barrier is never simply "picked from a catalog" but is always precisely calculated for the specific terrain and climatic conditions. Investing in systems calculated according to SP 116.13330 standards and manufactured with reference to leading global practices (WSL/SLF, ONR) guarantees uninterrupted operation for infrastructure facilities, even during the harshest snowy winters.