Which gas is the most common toxic component of smoke?

The most common toxic component of smoke is carbon monoxide. This gas is a byproduct of incomplete combustion, which occurs when there isn't enough oxygen present for a fuel to burn completely. In many fire scenarios, especially in enclosed spaces, the formation of carbon monoxide is prevalent because ample oxygen may not be available to support complete burning.

Carbon monoxide is particularly dangerous because it binds with hemoglobin in the blood more effectively than oxygen does, which can lead to hypoxia—a condition characterized by an insufficient supply of oxygen to the tissues. Symptoms of carbon monoxide poisoning can include headaches, dizziness, confusion, and, in extreme cases, can lead to loss of consciousness and death.

While other gases such as hydrogen cyanide and nitrogen dioxide are also hazardous, carbon monoxide is most frequently encountered in smoke from common materials like wood, plastics, and other household items during a fire. Therefore, understanding carbon monoxide's prevalence in smoke helps in recognizing the potential hazards during firefighting or rescue operations.