What must drivers ensure before swinging heavy loads over cabs?

Before swinging heavy loads over cabs, it is essential for drivers to ensure that the area is clear of obstacles. This is crucial for maintaining safety on the job site. A clear area minimizes the risk of accidents or unintended collisions, which could cause damage to equipment or injury to personnel. By checking the surroundings, drivers are acting proactively to safeguard not only themselves but also co-workers and bystanders who may be in the vicinity.

The other options, while relevant in other contexts, do not prioritize the immediate safety concern of ensuring a clear working area before proceeding with potentially dangerous maneuvers. For instance, the presence of a seated driver in the cab or personnel being accurately positioned, while important, does not address the risk posed by obstacles that can lead to accidents during the operation of heavy machinery. Lastly, the timing of the work shift has no bearing on the need for a safe operating environment, as proper safety practices should always be adhered to regardless of the time of day.