Under what condition can apprentice miners set temporary supports on a working section?

Apprentice miners can set temporary supports on a working section specifically when they are supervised by a certified miner. This requirement ensures that they receive the necessary guidance and oversight to perform such a critical task safely. The presence of a certified miner helps mitigate risks associated with setting supports, as temporary supports play a crucial role in maintaining the stability of the mine and ensuring the safety of all personnel in the area.

Supervision by a certified miner means that the apprentice can benefit from the experience and knowledge of someone who has been formally trained and has demonstrated competency in mining safety practices and support installation. This oversight is vital, as improper support installation can lead to hazardous conditions, including collapses or unintended falls.

The other conditions, such as feeling confident, working alone, or being on break, do not align with safety protocols established for mining operations. Confidence alone does not equate to the necessary training and experience required to set supports safely, and working alone would expose the apprentice to increased risk without the safety net of supervision. Being on break indicates that the apprentice is not in a position to engage in actual work-related tasks, further emphasizing the necessity of supervision for any activity in a working section.