Which statement indicates understanding about carbon monoxide poisoning?

• A. I should install smoke detectors in my home.
• B. Carbon monoxide will make you sick but it is not lethal.
• C. You can smell carbon monoxide, so it is easy to detect.
• D. I should have my furnace checked for leaks before turning it on.

Answer: (D)

Carbon monoxide poisoning is a hidden danger because CO is odorless, colorless, and can cause severe illness or death without warning. The best way to show understanding is to focus on preventing exposure by ensuring the heating system is safe before use. Having the furnace checked for leaks before turning it on directly addresses the source of potential CO production, reducing the risk of an unseen leak releasing CO into the home. This proactive step shows you recognize that prevention hinges on proper equipment maintenance rather than relying on senses or on detectors alone. In contrast, assuming you can smell CO is unreliable, since CO has no smell; and while smoke detectors help with fires, they do not reliably detect CO leaks unless they are CO detectors. CO can be lethal even at low levels, so maintenance before use is the most protective and directly relevant understanding.