Which of the following explains why sub-surface mining is more dangerous than surface mining?
Sub-surface miners deal with loud noises in addition to surface mining hazards such as toxic air conditions, sinkholes, and machine injuries.
Sub-surface miners deal with hazardous chemicals in addition to surface mining hazards such as toxic air conditions, sinkholes, and loud noises.
Sub-surface miners deal with machine injuries in addition to surface mining hazards such as toxic air conditions, sinkholes, and loud noises.
Sub-surface miners deal with toxic air conditions in addition to surface mining hazards such as sinkholes, machine injuries, and loud noises.