In which scenario is it unacceptable to use battery-powered devices near explosives?

Using battery-powered devices near explosives requires thorough consideration of safety protocols, particularly in environments classified as hazardous. The correct answer highlights the critical nature of equipment specifications when working with explosives.

Devices not rated for hazardous locations present significant safety risks because they might not have been designed to withstand the specific environmental conditions, such as igniting sparks or heat generated from their operation. Equipment that is not appropriately certified can potentially lead to accidental detonations or fires when exposed to explosive materials. This makes it unacceptable to use such devices in close proximity to explosives.

In contrast, battery-powered devices that are rated for hazardous locations are specifically designed to operate safely in environments where flammable materials may be present. Devices that are uncharged or firmly secured do not inherently guarantee safety either, as their operational state or physical restraint does not address the potential hazards posed by the device during operation. Thus, the use of non-certified equipment around explosives is a serious safety violation and can have catastrophic consequences.