Under the HVNL, which of the following is a key principle about load placement on a heavy vehicle?

1. Load must always be placed behind the rear axle for balance
2. Load must be placed, secured, and restrained to meet national loading performance standards
3. The driver alone is responsible for all loading decisions, even if loading staff made errors
4. A load is adequately restrained as long as it does not touch the sides of the tray