A fire building shall not be released until O2 levels are normal. Is this statement true or false?

The statement is true because ensuring that oxygen (O2) levels are normalized before releasing a fire building is a critical safety measure. Firefighting operations can lead to the displacement of oxygen within a structure due to smoke, combustion by-products, or firefighting efforts themselves. Normalizing O2 levels is essential to prevent respiratory hazards for both firefighters and any potential occupants or civilians who may re-enter the structure after the fire has been extinguished.

When O2 levels are within a normal range, it indicates a safe environment, helping to mitigate the risks of hypoxia or other respiratory issues that could arise from low oxygen levels. This practice is a standard protocol for fire safety as it ensures that the environment is habitable and poses no immediate danger once the firefighting efforts are concluded. Proper atmospheric monitoring before the release of any fire scene is crucial for the health and safety of all personnel involved and the community.