Safety of snow and ice constructions
In order to ensure safety, snow and ice constructions − particularly if large or intended to accommodate people − must be designed and built with great care. In practice at least the largest structures must be based on written construction design documents, including strength calculations.
The properties of snow and ice are strongly affected by the climate conditions in which their crystal structures were created. The properties of snow and ice constructions are influenced throughout their lifecycles by the conditions prevailing during construction. The location in which the snow or ice was made or collected also has a major impact on the material's properties. Therefore knowledge acquired about the properties of snow and ice crystals cannot necessarily be utilised as such in different areas: the design of constructions at seaside involves very different concerns from that of structures built inland.
Design should be based on user safety
User safety must be the primary concern in the design and maintenance of snow and ice constructions.
Issues to be considered in design include:
- step and stair safety;
- the need for handrails and banisters;
- slip prevention.
It is important to remember with regard to electrical appliances and cords that all appliances and connections used in snow and ice constructions must be suitable for outdoor use. All electrical appliances used must have protective insulation or protective earthing or operate on extra-low voltage. The casing of appliances intended for long-term outdoor use must be totally watertight. A residual-current device provides further protection in outdoor plug sockets.
Service providers must use risk assessments to determine whether a maximum number should be set for persons using the service at the same time. If it is found necessary to set a maximum number of users, the methods applied to monitor and, if necessary, restrict the number must also be decided.
Condition checks must take place every day
Because the shape of snow and ice constructions changes constantly, it is very important to check their structural safety and usability every day, even if weather conditions have remained favourable for this type of construction for a long period.
The service provider must determine the following:
- Who is responsible for monitoring the condition of the structures?
- Which issues must be particularly focused upon in the monitoring?
- How must observations made in the monitoring of structural condition be entered into the operational log or corresponding document?
- In which circumstances must the construction be taken out of use or its use be restricted?
- How must the decommissioning of the construction take place to ensure that the weakening or melting construction does not present any risk?
Photographing the structures regularly has proven to be a good practice in the monitoring of structural condition. Any changes in the shape of structures during the construction's lifecycle can be easily detected when photos are compared.
Snow and ice constructions may also attract people − even if their use is specifically prohibited. Good practices to ensure safety include breaking the construction down totally when it is taken out of use.