Why should you use chocks on a trailer not equipped with spring brakes when parked?

Using chocks on a trailer that is not equipped with spring brakes when parked is essential for safety, as it primarily serves the purpose of preventing the trailer from rolling away. Trailers without spring brakes rely solely on the vehicle's parking brakes to keep them stationary, which may not be sufficient in certain situations, especially on inclines or uneven surfaces.

Chocks create a physical barrier that stabilizes the trailer and ensures that it remains in place, mitigating the risk of accidental movement. This is vital for protecting both the trailer and surrounding environment, as an uncontrolled trailer can pose serious hazards, including damage or injury.

While other options may seem relevant, such as preventing swaying or providing traction, these do not address the most critical safety concern regarding the stationary position of the trailer when parked. Protecting the coupling system is also important, but it does not directly relate to the primary function of chocks in this context.