Which statement describes the effect of carbon monoxide at exposure levels of 6400 ppm?

The correct answer highlights the severe effects of carbon monoxide (CO) exposure at 6400 ppm, which is critically high and presents a significant risk to human health. At this concentration, carbon monoxide can quickly bind to hemoglobin in the blood, impairing the body’s ability to transport oxygen. The rapid onset of unconsciousness—occurring after just 2 to 3 breaths—is indicative of the acute toxicity of CO at such extreme levels of exposure.

Understanding this is crucial, as it emphasizes the danger of high concentrations of carbon monoxide and the need for immediate evacuation and medical attention in environments where such exposure could occur. The impact of carbon monoxide is time-sensitive, and recognizing the symptoms associated with varying levels of exposure is important for effective emergency response.