What is defined as an oxygen-enriched atmosphere?

An oxygen-enriched atmosphere is defined as an environment in which the concentration of oxygen exceeds the normal atmospheric level of approximately 21%. Specifically, an atmosphere is considered oxygen-enriched when it contains more than 23.5% oxygen by volume. This elevated level of oxygen can significantly enhance the combustion process, making materials that are typically non-combustible more likely to ignite and burn.

In contrast, levels below 19.5% oxygen indicate an oxygen-deficient atmosphere, which presents a risk for asphyxiation and other health hazards. Therefore, recognizing the threshold for an oxygen-enriched atmosphere is critical for ensuring safety during operations involving hazardous materials, as it impacts both fire safety and the health of workers in those environments. Understanding these thresholds is crucial for implementing appropriate safety measures and responding effectively to potential hazards in the workplace.