Here are the key risks of carbon monoxide when scuba diving:

• Contaminated air supply – Faulty compressors, poor maintenance, or inadequate filtration can introduce CO into tank air during filling
• Accelerated absorption at depth – Elevated partial pressure underwater causes faster CO absorption into the bloodstream compared to surface conditions
• Oxygen displacement – CO binds to hemoglobin 200 times more readily than oxygen, preventing oxygen transport to vital organs
• Masked symptoms – Early signs like headache, dizziness, and nausea can be mistaken for nitrogen narcosis, seasickness, or normal diving fatigue
• Impaired judgment – CO poisoning reduces cognitive function and decision-making ability, making it harder to recognize the problem or respond appropriately
• Delayed recognition – The colorless, odorless nature of CO means poisoning can progress significantly before symptoms become obvious
• Compromised emergency response – Confusion and disorientation from CO poisoning can impair a diver’s ability to surface safely or assist others
• Proximity to contamination sources – Dive shops with compressors near vehicle exhaust, generators, or other combustion sources increase risk of tank contamination
• Inadequate air testing – Facilities that don’t regularly test air quality or maintain proper compressor filtration systems pose ongoing risks
• Progressive deterioration – Symptoms worsen with continued exposure, potentially leading to unconsciousness underwater
• Long-term health effects – Even surviving CO poisoning can result in lasting neurological damage or cardiac complications
• Buddy system compromise – Both divers in a team may be affected simultaneously if breathing from contaminated air sources