Firefighters are constantly exposed to dangerous hazards while on the job. It’s critical that the air in their SCBA be free of contamination and safe to breathe. It’s important to have an understanding of how oxygen levels impact the human body and to employ proper monitoring of compressed breathing air.
The featured infographic shows the oxygen levels at which breathing air is severely compromised, putting humans at risk. Each percentage in the chart marks how the human body reacts to different levels of oxygen. Symptoms can range from impaired judgment, fatigue, unconsciousness, to death.
NFPA 1989 and CGA Grade D
Compressed breathing air regulations such as NFPA 1989 and CGA Grade D have set oxygen requirements to be between 19.5 and 23.5 percent. NFPA states that the oxygen content should not contain less than 19.5 percent and not be greater than 23.5% by volume. 19.5% oxygen content is the minimum for human breathing.
NFPA 1989 legally requires firefighters in Texas to comply with their breathing air regulations; however, many fire departments choose to test to this standard as an added safety precaution.