What percentage of carbon monoxide concentration in the blood can decrease peripheral and night visual acuity?

The percentage of carbon monoxide concentration in the blood that can lead to a decrease in peripheral and night visual acuity is 10%. At this concentration, carbon monoxide can significantly impair the ability of hemoglobin to transport oxygen, leading to hypoxia and subsequent visual disturbances. The human body, particularly the eyes, is sensitive to reduced oxygen levels. Peripheral vision and night vision are particularly affected by this condition because these functions depend on the health of rods and cones in the retina, which require adequate oxygen for optimal performance.

Higher concentrations of carbon monoxide would result in more severe impairments and symptoms, but a decrease in visual acuity can begin to manifest notably at the 10% saturation level. Understanding the relationship between carbon monoxide levels and visual function is critical for aeromedical assessments, especially for those at risk of exposure, such as pilots or individuals working at high altitudes.