How does an oxygen-deficient atmosphere affect combustible gas readings?

An oxygen-deficient atmosphere can lead to lower combustible gas readings because many gas detection systems rely on a certain concentration of oxygen to ensure accurate measurements. When oxygen levels drop, the combustion process within the detection system can be hindered, preventing it from accurately responding to the presence of flammable gases.

In an environment where there is not enough oxygen, gas detection devices may not activate or may provide misleading readings, showing lower concentrations of combustible gases than actually present. This is critical in mining operations, where understanding the true levels of combustible gases is necessary for ensuring the safety of workers and preventing hazardous situations.

The other options do not accurately reflect the behavior of combustible gas readings in an oxygen-deficient environment. Accurate readings would indicate proper functioning of the measurement equipment, which is not the case in these conditions, while fluctuating readings might suggest interference from other factors, but they do not directly relate to the reduction of oxygen levels affecting gas detection.