What you should do before entering a docked trailer you should always check what?

Before entering a docked trailer, you should always check that the trailer is properly secured to the dock and that wheel chocks are in place to prevent movement. Additionally, verify that the trailer's doors are closed and secured, and inspect the area for any hazards such as debris or spills. It's also important to ensure that the trailer is not overloaded and that you have the proper personal protective equipment (PPE) if necessary.