What is the acceptable concentration level of oxygen in confined spaces?

The acceptable concentration level of oxygen in confined spaces is critically important for ensuring the safety and health of individuals who may work or enter such environments. Levels between 19.5% to 23% are considered safe for respiratory health. This range indicates that there is sufficient oxygen for normal physiological functions while also allowing for adequate safety margins.

An oxygen concentration below 19.5% can lead to hypoxia, where there is insufficient oxygen to support human life, potentially causing serious health risks and impairments in cognitive and physical performance. Moreover, concentrations above 23% can increase the risk of fire and explosion, as higher oxygen levels can make environments more conducive to combustion.

Therefore, the range of 19.5% to 23% is the established safe zone that balances sufficient oxygen availability for breathing while preventing the dangers associated with both inadequate and excessive oxygen levels in confined spaces. Understanding these thresholds is crucial for inspectors and workers involved in operations within confined areas.