In the incident two loaders were operating on the site's stockpile area when they collided.
The first loader was picking up a load when a second loader pulled up behind, with the latter's driver relaying his position to the driver in front.
However, the driver of the first loader suddenly reversed his loader and hit the bucket of the second loader as it passed behind.
The regulator said the incident was due to a lack of communication.
Effective communication procedures should be in place to keep mobile equipment working in close proximity safely separated, with supervisors to monitor compliance.
The regulator added that mobile equipment should be equipped with collision detection and avoidance systems while visual aids and segregation processes should be available and implemented before relying on procedural controls.