What is the minimum percentage of oxygen that non-flammable gases avoid ignitability at?

Non-flammable gases are defined by their inability to cause or support combustion under standard atmospheric conditions. The minimum percentage of oxygen in the air is crucial for assessing the ignitability of these gases. Generally, non-flammable gases are considered to be safe from ignitability when the oxygen concentration in the air is at or below a specific threshold.

The correct answer indicates that the minimum percentage of oxygen at which non-flammable gases avoid ignitability is 12 percent. At this level, the concentration of oxygen is insufficient to sustain combustion for flammable materials. Therefore, if the oxygen concentration is kept at or below this threshold, the risk of igniting non-flammable gases is minimized, making environments safer for handling and storage.

Gases at this concentration effectively reduce the probability of ignition, thus enabling safe operational conditions for materials classified under non-flammable gases.