Carboxyhemoglobin levels during a submarine patrol

One of the major contaminants from tobacco smoking aboard a nuclear submarine is carbon monoxide (CO). While this gas is controlled to 15 parts per million or lower by catalytic burners, there still remains a residual low level in the atmosphere. This study has shown that, on one submarine, the average ambient concentration was 7 ppm, which produced an average carboxyhemoglobin level in 15 nonsmokers of 2.1%, 1.7%, and 1.7% at the start, middle, and end of a 40-d patrol. Because submariners are generally healthy and young, it is concluded that CO exposures at these ambient levels do not constitute a major risk factor to the physiological well-being of these submariners, nor are they expected to cause any decrement in performance.