Final answer:
The top of a load of loose materials must be securely covered during transport to prevent escape, using tools like tarps fitted with stainless steel washers. This applies to various transport modalities, including vehicles and tube trains.
Step-by-step explanation:
When transporting loose materials, the top of the load must be covered securely to prevent the materials from escaping due to movement or environmental factors such as wind. This is relevant in various forms of transportation, including roadside vehicles and water transport. In construction and environmental management, technology is implemented to secure loads, such as the use of plastic tarps combined with geotextile for coverings that are sturdy and resistant to traction.
These covers are often fitted with stainless steel washers to ensure they remain in place. Other transportation methods that require secure containment include container vehicle bodies and tube trains (metro trains), as well as methods for deploying materials under the tarp in marine environments that are designed to be watertight using rubber rings from bicycle air tubes and PVC capsules.