What should the surface be like for safe operation of cribbing?

For safe operation of cribbing, the surface must be firm and flat. This quality of the surface is critical because it provides the necessary stability and support for the load being lifted. A firm surface helps to prevent settling or shifting, which could lead to instability and increased risk of accidents. Flatness ensures that the cribbing is evenly distributed, reducing the likelihood of tipping or collapsing under load.

Choosing a surface that is soft and uneven would compromise the effectiveness of the cribbing, as it could lead to inadequate support and an increased risk of failure. While concrete is a strong material, it is not the only suitable option as long as the surface characteristics meet the requirements for firmness and flatness. Therefore, the specification for a firm and flat surface underscores the importance of ensuring that the foundation on which the cribbing rests is capable of safely supporting the load during operations.