What is the primary use of flatracks in cargo transport?

Flatracks are specifically designed to accommodate large, heavy cargo that may not fit into standard shipping containers. Their structure features a flat platform with minimal sides and no roof, allowing for easy loading and unloading of oversized items such as machinery, construction materials, or vehicles. This design makes them ideal for cargo that needs to be securely fastened but cannot be contained within a traditional container's confines.

In contrast, the other options address different uses for cargo transport. While transporting hazardous materials safely requires specific types of containers that comply with safety regulations, flatracks do not provide the necessary containment or protection. Loading lightweight bulk items typically involves different types of containers or trailers designed for such cargo, as flatracks are more suited for heavier, bulkier loads. Regarding temporary storage, flatracks are not intended for this purpose; they are primarily used for transport rather than long-term storage solutions.