What is a toxic gas commonly produced by fire?

What is a toxic gas commonly produced by fire?

• A. Carbon monoxide
• B. Oxygen
• C. Nitrogen
• D. Hydrogen cyanide

Answer: (D)

When fuels burn, not all of them burn cleanly. In incomplete combustion, carbon-based materials release carbon monoxide as a common toxic gas. It’s especially dangerous because it’s colorless and odorless, so you can inhale it without noticing. Carbon monoxide grabs hemoglobin in your blood much more strongly than oxygen does, forming carboxyhemoglobin and dramatically reducing the blood’s ability to carry oxygen to the body's tissues. That lack of oxygen can quickly lead to dizziness, confusion, loss of consciousness, and can be fatal with enough exposure.

Hydrogen cyanide can also be produced in certain fires, particularly when plastics or other nitrogen-containing materials burn, and it’s also highly toxic. But carbon monoxide is the gas most typically encountered as a fire byproduct, which is why it’s the main concern in smoke inhalation scenarios. Oxygen and nitrogen aren’t the toxic gases produced in this same context.