What is the minimum oxygen level that should not be exceeded in confined spaces?

The minimum oxygen level that should not be exceeded in confined spaces is 20%. This threshold is critical for ensuring safety in environments where adequate ventilation may be limited, and oxygen levels can vary significantly due to factors such as gas consumption or displacement by other gases.

Oxygen is vital for human respiration; healthy atmospheric oxygen concentrations range from 19.5% to 23.5%. Levels below 19.5% can start to present health risks, including dizziness, impaired judgment, and even unconsciousness in more severe cases. At 20%, the oxygen level is still within a safe range and allows for normal physiological function, making it an important standard in safety protocols for confined spaces.

Maintaining oxygen levels at or above 20% ensures that workers have a sufficient supply for safe breathing while in such locations, therefore, a minimum threshold of 20% is the most widely accepted in safety guidelines.