Which percentage of oxygen deficiency is considered dangerous in mining environments?

Which percentage of oxygen deficiency is considered dangerous in mining environments?

• A. 14%
• B. 16%
• C. 18%
• D. 20%

Answer: (B)

Oxygen deficiency becomes dangerous when the amount of oxygen in the air drops to about 16%. Normal air contains roughly 21% oxygen, so once the level falls to 16%, the body's tissues receive far less oxygen than they need. This level impairs brain function and coordination quickly, leading to dizziness, headaches, confusion, and impaired judgment. As oxygen availability continues to fall, unconsciousness and life-threatening complications can follow, making immediate evacuation or rescue essential. So, at 16% oxygen, the atmosphere is already considered dangerous for miners, which is why this level is highlighted as the threshold. The other options are either not deficient enough to pose an immediate danger (18% or 20%), or represent an even more severe deficiency (14%), which is indeed extremely hazardous but beyond the standard recognition of the danger threshold.

Oxygen deficiency becomes dangerous when the amount of oxygen in the air drops to about 16%. Normal air contains roughly 21% oxygen, so once the level falls to 16%, the body's tissues receive far less oxygen than they need. This level impairs brain function and coordination quickly, leading to dizziness, headaches, confusion, and impaired judgment. As oxygen availability continues to fall, unconsciousness and life-threatening complications can follow, making immediate evacuation or rescue essential.

So, at 16% oxygen, the atmosphere is already considered dangerous for miners, which is why this level is highlighted as the threshold. The other options are either not deficient enough to pose an immediate danger (18% or 20%), or represent an even more severe deficiency (14%), which is indeed extremely hazardous but beyond the standard recognition of the danger threshold.