What is the primary use of a rescue breathing apparatus?

The primary use of a rescue breathing apparatus is to provide air to personnel who are trapped in environments filled with smoke or toxic fumes. In situations where visibility is compromised and the air quality is unsafe due to smoke or the presence of harmful gases, this apparatus ensures that individuals can breathe safely while they navigate through hazardous areas, such as during firefighting or rescue operations.

This equipment is critical for enabling rescuers to perform their duties without being asphyxiated or poisoned by the contaminants in the air, allowing them to save both themselves and others in perilous situations. The other choices pertain to functions that are not the primary focus of a rescue breathing apparatus, reinforcing the importance of its specific role in maintaining breathable air in emergency scenarios.