The ground load is the unit weight of the undisturbed snow on the ground at the buiding site. Most ground loads are estimated from snowpack observations a considerable distance from the building site and adjusted for differences in elevation, exposure, and local climate. Due to lack of better information, many ground loads are estimated from snow depth observations with rainfall added. The methods for estimating roof loads from ground loads and from climate information have received considerable attention in recent years. Analytical models of snow accumulation, physical modelling in wind tunnels, and full scale observations on roofs were applied.
Many activities concerned with snow contain a risk.
In snow engineering, risk assessment has been applied for land-use planning in avalanche paths and snow loads on buildings. For all applications, tolerable risk levels should be defined by making comparisons with other hazards such as fire, floods, flying, boating, and injury in skiing. The tolerable risk levels should be clear and understandable by professionals, management, and politicians. Cost-benefit studies are closely related to risk analysis. Studies should be carried out as examples of whether or not an avalanche control is worthwhile for specific applications.