What are the safe minimum and maximum levels for oxygen in the workplace?

The safe minimum and maximum levels for oxygen in the workplace are typically defined to ensure a safe breathing environment for workers. The correct choice specifies a minimum oxygen level of 19.5% and a maximum of 23.5%.

A minimum level of 19.5% is crucial because oxygen concentrations below this threshold can lead to hypoxia, which results in issues such as impaired cognitive function, reduced physical performance, and in more severe cases, loss of consciousness. This level aligns with established safety standards, such as those from the Occupational Safety and Health Administration (OSHA) and other relevant organizations, which emphasize the importance of maintaining adequate oxygen levels for worker safety.

On the upper end, a maximum oxygen level of 23.5% reduces the risk of flammability and helps avoid the dangerous effects that can occur with overly rich oxygen environments. High concentrations of oxygen can significantly enhance the flammability of materials, creating hazards that could lead to fire or explosions.

This combination ensures that the oxygen level in the workspace remains within a range that supports health and safety while minimizing risks associated with both low and high oxygen concentrations. Thus, the correct answer provides a scientifically supported and regulatory-compliant range for oxygen levels in the workplace.