What work is permissible in the face areas while boreholes are being charged?

The correct answer is focused on the crucial safety measures that are necessary when boreholes are being charged with explosives. During this phase, only activities directly related to timbering and general safety are permissible. This limitation is essential because the process of charging boreholes introduces hazards, including the risk of unintentional detonation and injuries.

Timbering work is often necessary to support the area and ensure structural integrity, while general safety measures can include ensuring the environment is secure for workers and managing potential hazards. The emphasis on these types of work allows for maintaining safety protocols without exacerbating risks.

The other types of work mentioned, such as maintenance, loading explosives, or drilling new holes, present higher risks during the charging process and could jeopardize the safety of all workers in the vicinity. Therefore, restricting activities to those that enhance safety and support the ongoing operations in a controlled manner is critical in ensuring a safe working environment.