Who is permitted to be inby the operating controls of the roof bolting machine at a working face that is not completely supported?

The correct answer highlights the critical safety regulations in mining operations, particularly regarding the use of heavy machinery like roof bolting machines. In mining contexts, a working face that is not completely supported poses significant risk due to potential rock falls or other hazards. Therefore, safety protocols dictate that no personnel should be positioned inby the operating controls of such machinery in these dangerous conditions.

This regulation is in place to protect workers from the inherent risks associated with unsupported areas, ensuring that all operations are conducted under safe conditions. The emphasis on a completely stable environment before permitting personnel to operate machinery reflects the industry's commitment to maintaining the highest safety standards.

While other roles may have varying responsibilities on-site, including trained operators, site supervisors, and qualified technicians, the overarching principle is that safety comes first. Thus, restricting access to the area inby the operating controls of the roof bolting machine when it is not fully supported is a necessary precaution to prevent accidents and ensure worker safety.